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1

Spangler, Philip. "Excavations." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1406140330.

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2

Goessling, Sybil Elizabeth Hatch. "Interactive design of braced excavations." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/45728.

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Construction of braced excavations in major urban areas has increased over the last few decades. It is a major concern of the designer to limit ground movement around an excavation in order to prevent damage to adjacent structures, utilities and roads. Existing design methods can accurately predict ground and wall movement of a braced excavation, but the calculations become complex when multiple construction stages are considered, or if different design schemes are compared. This thesis presents an interactive personal computer program (called MOVEX) to facilitate braced excavation design. Using input variables for wall stiffness, strut stiffness, and strut spacing, MOVEX includes four design options that allow the designer to adjust the variables in order to develop the optimal bracing design. Details of the design theory, input and output data, and a user's guide are included in this thesis. In addition, the settlement of sand due to pile driving was investigated. A predictive method is presented that relates sand densification to the ground acceleration caused by pile driving.
Master of Science
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3

Shao, Yong C. "Information feedback analysis in deep excavations." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/20055.

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4

Rizkalla, Maged Kamal. "Elasto-viscoplastic modelling of rock excavations." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60595.

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The first part of the thesis describes the concepts of viscoplasticity as a continuous plasticity theory highlighting different kinds of yield functions, plastic potentials and visocplastic constitutive laws.
A 2-dimensional elasto-viscoplastic finite element model for stress/stability analysis of mining excavations has been developed for use on microcomputers. An iterative explicit time stepping scheme is implemented. The program uses automatic time-step calculator based on equations giving a limit on the time step in an attempt to prevent numerical instability when common forms of isotropic yield functions and plastic potentials are used in the viscoplastic solution. When the input data are read parallel to the analysis undertaken the user can simulate compound behaviour by stopping the analysis, examining the results graphically and restarting it again and possibly implementing a certain decision in the subsequent appended input. This also imposes no limit on the number of time stations at which instantaneous changes like elements cut, elements backfilled, loads added or simply outputs are required. The program is equipped with graphical pre- and post- processors.
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5

Easton, Donald Fyfe. "Schliemann's excavations at Troy, 1870-1873." Thesis, University College London (University of London), 1989. http://discovery.ucl.ac.uk/1317763/.

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This study is based on Schliemann's unpublished Troy excavation note books from 1870-73. It attempts to reconstruct his activities, to locate and identify the features he found, and to stratify and date the several thousand objects he recorded. There is some degree of synthesis with the later findings of Dörpfeld and Blegen, and a review, in the light of all these findings, of the chronology of the Bronze Age strata. The study covers all periods from Early Bronze Age to Byzantine, and all classes of material. A reconstructed contour-plan permits a new and closer understanding of Schliemann's progress. Fifty-two areas of work are distinguished in each of which an outline stratigraphy can be reconstructed. Objects are assigned to specific strata, although Schliemann's frequent failure to specify from which trench which objects came can inject varying degrees of uncertainty into the operation. The sequence of fortifications on the North side of the site is greatly clarified, especially for Troy II and VI. Buildings in the citadel interior are more closely dated, and the sequence in Troy II is substantially re-organised to allow for at least twelve building-phases. The earth-movements supposed to have demolished Troy VI are unlikely to have antedated late VIIa. Troy I-II.4 belong to EBII (c.3000-2465); wheelmade plates and one-handled tankards first appear in II.1. Troy II.5-III belong to EBIII (c.2465-2005); two-handled cups and tankards appear in II.5 after an increase of wheelmade plain ware in II.4. Troy III is contemporary with early Middle Helladic. Troy IV-V belong to the Anatolian Middle Bronze Age (c.2005-1712), and VI-VII are purely Late Bronze Age (c.1712-1070). VIh was destroyed c.1270(?), probably around the end of LHIIIBl, and VIIa was destroyed c.1190(?) during LHIIIC.
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6

SPRINGER, FERNANDA OTTO. "DEFORMABILITY ANALYSIS OF SOIL NAILING EXCAVATIONS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2001. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=1983@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
A utilização de inclusões passivas para reforços de solos, técnica comumente conhecida como solo grampeado, vem tendo aceitação crescente junto a profissionais de engenharia civil, em especial no Rio de Janeiro. Esta técnica, porém, carece de um estudo detalhado sobre a influência dos parâmetros relevantes na deformabilidade de maciços grampeados. Os grampos são inclusões rígidas, instaladas suborizontalmente, sem tensão ou trecho livre, pois as barras de aço são introduzidas em um furo preenchido com calda de cimento. As forças axiais nos grampos são obtidas através da descompressão lateral causada pela escavação do solo. O grampeamento é feito na massa de solo à medida que escavações são executadas em etapas, obtendo se uma zona reforçada que atua como suporte da massa de solo posterior, sem reforço. A face frontal da escavação é usualmente protegida por concreto projetado, sem funções estruturais. Esta pesquisa objetiva avaliar a influência dos diversos parâmetros geotécnicos e geométricos no comportamento tensão deformação de escavações grampeadas com face vertical e superfície do terreno horizontal. A análise paramétrica foi realizada pelo FLAC (Fast Lagrangian Analysis of Continua) que é um programa computacional baseado no método das diferenças finitas. Este programa simula o comportamento bidimensional de estruturas reforçadas, constituídas de solo e ou rocha, que possam ser submetidos a escoamento plástico quando o limite de resistência é atingido. Os resultados mostram que o módulo de Young (E) e a coesão do solo (c) são de grande relevância para o projeto de estruturas grampeadas. Adicionalmente, as análises indicam que a resistência ao cisalhamento na interface solo-grampo (qs) é também um parâmetro importante, particularmente nos casos com grampos de comprimento (L) inferior a 80 por cento da profundidade de escavação (H) (L/H < 0,80). Recomenda-se que o valor de qs seja determinado diretamente a partir de ensaios de arrancamento no campo. No que se refere à inclinação dos grampos, os resultados mostram que não há diferenças significativas nos deslocamentos do maciço reforçado para lambda menor ou igual a 10 graus. Estes resultados são particularmente interessantes do ponto de vista de execução, pois inclinações da ordem de 10 graus facilitam os procedimentos de injeção no campo. Os resultados obtidos nesta pesquisa indicam o uso de comprimentos de grampos maiores que 70 por cento da altura de escavação (L/H > 0,70) na técnica do solo grampeado.
The use of passive inclusion for soil reinforcements, technique usually known as soil nailing, has been gaining growing acceptance within civil engineering professionals,especially in Rio de Janeiro. However this technique lacks a more detailed study on the elevant parameters influencing the deformability of soil nailed masses. The nails are rigid inclusions, sub horizontally positioned, without tension or free space between the nail and the surrounding soil mass. The axial forces on the nails are developed due to lateral decompression caused by soil excavation. As the excavation stages proceed, the nails are successively being installed, producing a reinforced zone, which acts as a support for the soil mass. The frontal face of the excavation is usually protected by shotcrete, and has no structural functions. This research aims at evaluating the influence of the various geotechnical and geometric parameters on the stress strain behavior of nailed excavations, with vertical face and horizontal soil surface. The parametric analysis was performed using FLAC (Fast Lagrangian Analysis of Continua), which is a computer program based on the finite difference method. This program simulates bi dimensional behavior of reinforced structures of soils and or rocks,which may be submitted to plastic flow when the strength limit is reached. The results show that the Youngs modulus (E) and soil cohesion (c ) have a very significant influence on the displacement of a soil nailing structure. The analysis also indicates that the mobilized shear strength at the soil nail interface (qs) is also an important parameter, particularly for nail lengths (L) smaller than 0,80 of the excavation height (H) (L/H < 0,80). It is therefore recommended that qs be directly determined by pullout in situ tests. Regarding nail inclination the results suggests no significant influence on the reinforced soil mass displacement for alpha less or equal than 10 degrees. These results are particularly relevant for engineering practice, because a 10 degrees inclination facilitates grouting injections in the field. The results in this research indicates the use of nail lengths (L) greater than 0,70 of the excavation height (H) (L/H greater than 0,70) in soil nailing technique.
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7

Whelan, Michael P. (Michael Paul) 1968. "Performance of deep excavations in Boston." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/37790.

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8

Hashash, Youssef M. A. "Analysis of deep excavations in clay." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/13199.

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9

Bentler, David J. "Finite Element Analysis of Deep Excavations." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30767.

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This dissertation describes enhancements made to the finite element program, SAGE, and research on the performance of deep excavations. SAGE was developed at Virginia Tech for analysis of soil-structure interaction problems (Morrison, 1995). The purpose of the work described in this text with SAGE was to increase the capabilities of the program for soil-structure analysis. The purpose of the research on deep excavations was to develop a deeper understanding of the behavior of excavation support systems. The significant changes made to SAGE during this study include implementation of Biot Consolidation, implementation of axisymmetric analysis, and creation of a steady state seepage module. These changes as well as several others are described. A new manual for the program is also included. A review of published studies of deep excavation performance and recent case histories is presented. Factors affecting the performance of excavation support systems are examined, and performance data from recent published case histories is compared to data from Goldberg et al.'s 1976 report to the Federal Highway Administration. The design, construction, and performance of the deep excavation for the Dam Number 2 Hydroelectric Project is described. Finite element analyses of the excavation that were performed with SAGE are presented and discussed.
Ph. D.
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10

Xia, Huanliang. "An analysis for braced excavations in clay." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0010/NQ42487.pdf.

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11

Abela, Jeanette Mireille. "Blinding Struts in Cut-and-Cover Excavations." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511839.

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12

Batten, Melanie. "Prop loads in two large braced excavations." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242719.

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13

Hsiung, Bin-Chen. "Engineering performance of deep excavations in Taipei." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393013.

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14

NOGUEIRA, CHRISTIANNE DE LYRA. "NON LINEAR ANALYSIS OF EXCAVATIONS AND EMBANKMENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1998. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2136@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
O principal objetivo desta tese consiste no desenvolvimento e aplicação de um programa computacional, ANLOG (Análise Não Linear de Obras Geotécnicas), para análises de problemas geotécnicos com acoplamento de fluxo e deformação, e considerando relações constitutivas não lineares na modelagem do solo. A nível global, a solução do sistema de equação não linear originado da formulação via MEF deste problema é feita através do método de Newton-Raphson Modificado com incrementos automáticos de carga e tempo. Enquanto que, a nível local, a equação constitutiva é integrada utilizando-se um algoritmo de integração de tensão explícito com subincrementos. Modelos não lineares elástico (hiperbólico) e elastoplásticos (Camclay Modificado, Lade e Lade-Kim) são utilizados para representar o comportamento tensão-deformação-resistência do solo. As metodologias de ligar a gravidade e a proposta por Brown e Booker (1985) são usadas para simular numericamente, respectivamente, aterros e escavações. Análises preliminares de aterros e escavações são apresentadas nas quais pode-se observar que a resposta é função do tempo e altamente dependente do coeficiente de permeabilidade e da velocidade de solicitação. As situações drenada e não drenada são casos particulares de uma análise acoplada. Com respeito ao emprego da técnica de incremento automático de carga e tempo mostra-se que sua utilização é fundamental para definição do tamanho do incremento mais adequado a ser adotado na solução incremental-iterativa. Quanto ao algoritmo de integração de tensão adotado é mostrado que o erro cometido na verificação da condição de consistência diminui exponencialmente com o aumento do número de subincrementos. Por fim, o programa ANLOG é utilizado para análise da escavação experimental de Camboinhas (Silva, 1979). Comparações entre os deslocamentos numéricos e os de campo apresentam uma razoável concordância. Entretanto, as poro- pressões numéricas variam em torno de 10 por cento a 30 por cento do valor inicial, enquanto que no campo essa variação foi menor que 3 por cento.
The main objective of this thesis consists on the development and application of a computational program, ANLOG (Non Linear Analysis of Geotechnical Constructions), to analyse geotechnical problems coupling flow and deformation, and considering constitutive non-linear relations for the soil modelling.At the global level, the solution of the non linear system of equations, generated by the FEM formulation of this problem, is done using the Newton-Raphson Modified method with automatic load and time increments. On the other hand, at the local level, the constitutive equations are integrated using the explicit algorithm of stress integration with sub steps. Non-linear models, elastic (hyperbolic) and elastoplastic (modified Camclay, Lade and Lade-Kim) are utilised to represent the stress-strain-strength behaviour of the soil. The procedures of turn on gravity and the one proposed by Brown and Booker (1985) are used to simulate numerically, respectively, embankments and excavations.Initial analyses of excavations and embankments are performed in which it can be observed that the response is a function of time and depends strongly on the permeability coefficient and the loading velocity. In particular, drained and undrained situations are special cases of a coupling analysis. With respect to the use of the automatic load and time increment, it is shown that its use is fundamental to define the best increment size to adopt in the incremental iterative solution. About the stress integration algorithm utilised, it is shown that the error in the consistency condition decreases exponentially with the number sub steps. Finally, the ANLOG program is used to analyse the experimental excavation of Camboinhas (Silva, 1979). Comparisons between numerical and field displacements present a reasonable agreement. However, the pore pressure given by the numerical simulation varied between 10 percent to 30 percent in relation to its initial value, whereas in the field this variation was smaller than 3 percent.
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TITO, JOSE CARLOS SOLIS. "NUMERICAL ANALYSIS OF DEEP EXCAVATIONS IN SOIL." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=24688@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Na atualidade, devido à necessidade de realizar obras de engenharia de grande porte em ambiente urbano, o engenheiro defronta-se muitas vezes com o desafio de executar escavações profundas, as quais devem ser projetadas para serem estáveis e limitar deformações a níveis aceitáveis. Uma escavação profunda estável é aquela cujas paredes não colapsam e o seu fundo não experimenta levantamento descontrolado. Deformações do solo podem afetar construções vizinhas, vias urbanas e outras instalações públicas, com consequências que dependem tanto da magnitude quanto do padrão do movimento do solo ao redor da escavação. A previsão do comportamento de uma escavação profunda envolve análises tanto de estabilidade quanto de deformação. Análises de estabilidade podem em geral ser feitas através de métodos de equilíbrio limite, mas as análises de deformações, por outro lado, são mais difíceis de serem previstas, necessitando do auxilio de métodos numéricos. Nesta dissertação, o comportamento de escavações profundas é investigado numericamente pelo método de elementos finitos, com especial atenção à ocorrência de deformações, para cuja previsão requer-se a utilização de modelos constitutivos que representem muitos dos aspectos de comportamento de solos reais.
At the present, due to the need for engineering works of large scale in urban environment, the engineer is confronted often with the challenge of performing deep excavations, which should be designed to be stable and with acceptable levels of deformations. A stable deep excavation is that, whose walls do not collapse and its base does not experience uncontrolled heave. Soil deformations can affect neighboring buildings, urban roads and other public facilities, with consequences that depend on both the magnitude and the pattern of the movement of the soil around the excavation. The prediction of the behavior of a deep excavation therefore involves stability analysis as well as deformation analysis. Stability analysis can generally be made through limit equilibrium methods, but deformation analyses are more difficult to predict, requiring the assistance of numerical methods. In this dissertation the behavior of deep excavations is numerically investigated by the finite element method, with special attention to the occurrence of deformations, for this prediction requires the use of constitutive models that represent many aspects of behavior of real soils.
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Dourlet, Sébastien. "Étude expérimentale de deux excavations à Louiseville." Master's thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/38203.

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Le présent projet porte sur l’étude du comportement de deux excavations réalisées dans l’argile marine de l’est du Canada. Une tranchée à paroi verticale et une tranchée avec une pente de 32˚ ont été excavées sur le site expérimental du Ministère des Transports du Québec situé à Louiseville. Une revue de la littérature met en lumière l’aspect législatif et les règles directrices encadrant les travaux de fouille, le comportement théorique des excavations et plusieurs histoires de cas. Le projet contient une caractérisation géotechnique du sol basée sur des essais de laboratoire et des essais in situ. Une description détaillée du système d’acquisition, des capteurs, des branchements et du traitement des données est réalisée. Les mouvements de terrain observés, les variations de pressions interstitielles et les déformations ont fait l’objet d’une analyse pour rendre compte de leurs interactions. Les sols rencontrés lors de l’excavation sont un dépôt d’argile silteuse surmonté d’une croûte argileuse fissurée de 2 m d’épaisseur. Le dépôt est constitué d’une fraction argileuse de 80%, avec un indice de plasticité de 52% et un indice de liquidité de 1,1. La résistance mesurée au scissomètre varie 19 kPa à 2 m de profondeur à 60 kPa à 19,5 m. La sensibilité moyenne au cône tombant est de 20 et le ratio de surconsolidation, OCR, est de 4,3 à 2,2 m et décroit à 3,9 à 3,41 m de profondeur. La tranchée verticale a atteint une profondeur de 5 mètres avant la rupture, soit 5 heures 30 minutes après le début de l’excavation. La tranchée talutée a atteint une profondeur de 4,2 mètres et a été laissée ouverte 90 jours sans que des mouvements de sol soient observés. Un essai de chargement a été réalisé sur 3 jours afin de faire réagir le sol derrière la pente, mais la rupture n’a pas été atteinte.
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Lieske, Rosemary. "Izapa Group B: Excavations, Burials, and Offerings." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4305.

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Izapa, a Late Preclassic regional center located in southern Mexico, was heavily excavated by the New World Archaeological Foundation from 1961-1965. However, much remains unclear regarding the details of those excavations, specifically in regards to Group B. In this thesis I hope to present important details derived from those excavations in a way that is meaningful and useful. The purpose of this thesis project is to: (1) reconstruct the excavation history of Izapa Group B, (2) to provide a reconstruction of Group B's architectural history as revealed through the excavations, and (3) to identify and present descriptions of the contents and context of the plaza's numerous burials and offerings. Group B, containing the oldest known constructions at Izapa, is a special place and vital to understanding the growth and development of Izapa as a regional center.
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Hassell, Rhett Colin. "Corrosion of rock reinforcement in underground excavations." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/1247.

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The effect of corrosion on the performance of rock support and reinforcement in Australian underground mines has not been widely researched and is generally not well understood. This is despite the number of safety concerns and operational difficulties created by corrosion in reducing the capacity and life expectancy of ground support. This thesis aims to investigate corrosion and relate how the environmental conditions in Australian underground hard rock mines impact on the service life of rock support and primarily rock reinforcement. Environmental characterisation of underground environments was completed at a number of mine sites located across Australia. This provided an improved understanding of the environmental conditions in Australian underground hard rock mines. Long-term testing on the impact of corrosion on the load bearing capacity of reinforcement and support under controlled experimental conditions was conducted in simulated underground environments. Rock reinforcement elements were examined in-situ by means of overcoring of the installed reinforcement and surrounding rock mass. Laboratory testing of the core determined changes in load transfer properties due to corrosion damage. These investigations provided an excellent understanding of the corrosion processes and mechanisms at work. Corrosion rates for a range of underground environments were established through the direct exposure and evaluation of metallic coupons in underground in-situ and simulated environments.It was found that the study of corrosion is challenging due to the time required to gather meaningful data. In particular, the wide range of materials that comprise ground support systems means that it is impossible to examine all the possible combinations of variables and their potential influence on the observed levels of corrosion and measured corrosion rates. Despite these challenges, the systematic investigation has resulted in new corrosivity classifications for both groundwater and atmospheric driven corrosion processes for various reinforcement and support systems used in the Australian underground mining industry. Previous corrosivity classifications were not found applicable. Furthermore, these new corrosivity classifications are simpler than previous classifications and corrosion rates may be predicted from readily obtained measurements of ground water dissolved oxygen and atmospheric relative humidity. Different types of reinforcement and surface support systems have been rated with respect to their corrosion resistance and estimates have been made for the expected service life for various rates of corrosion.
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Hassell, Rhett Colin. "Corrosion of rock reinforcement in underground excavations." Curtin University of Technology, Western Australian School of Mines, Dept. of Mining Engineering and Surveying, 2008. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=17986.

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The effect of corrosion on the performance of rock support and reinforcement in Australian underground mines has not been widely researched and is generally not well understood. This is despite the number of safety concerns and operational difficulties created by corrosion in reducing the capacity and life expectancy of ground support. This thesis aims to investigate corrosion and relate how the environmental conditions in Australian underground hard rock mines impact on the service life of rock support and primarily rock reinforcement. Environmental characterisation of underground environments was completed at a number of mine sites located across Australia. This provided an improved understanding of the environmental conditions in Australian underground hard rock mines. Long-term testing on the impact of corrosion on the load bearing capacity of reinforcement and support under controlled experimental conditions was conducted in simulated underground environments. Rock reinforcement elements were examined in-situ by means of overcoring of the installed reinforcement and surrounding rock mass. Laboratory testing of the core determined changes in load transfer properties due to corrosion damage. These investigations provided an excellent understanding of the corrosion processes and mechanisms at work. Corrosion rates for a range of underground environments were established through the direct exposure and evaluation of metallic coupons in underground in-situ and simulated environments.
It was found that the study of corrosion is challenging due to the time required to gather meaningful data. In particular, the wide range of materials that comprise ground support systems means that it is impossible to examine all the possible combinations of variables and their potential influence on the observed levels of corrosion and measured corrosion rates. Despite these challenges, the systematic investigation has resulted in new corrosivity classifications for both groundwater and atmospheric driven corrosion processes for various reinforcement and support systems used in the Australian underground mining industry. Previous corrosivity classifications were not found applicable. Furthermore, these new corrosivity classifications are simpler than previous classifications and corrosion rates may be predicted from readily obtained measurements of ground water dissolved oxygen and atmospheric relative humidity. Different types of reinforcement and surface support systems have been rated with respect to their corrosion resistance and estimates have been made for the expected service life for various rates of corrosion.
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Bovy, Kristine M. "Effects of human hunting, climate change and tectonic events on waterbirds along the Pacific Northwest coast during the late Holocene /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6548.

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El, Arja Hiba. "Contribution à la modélisation numérique des excavations profondes." Thesis, Paris Est, 2020. http://www.theses.fr/2020PESC2034.

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Ce travail aborde différents aspects de la modélisation numérique des mouvements de sol induits par la réalisation des excavations profondes. Le premier objectif est de définir un modèle de comportement qui inclut un mécanisme permettant de bien représenter la cuvette de tassement derrière un écran de soutènement. Le deuxième objectif est de contribuer à la justification des états limites ultimes des ouvrages de soutènement selon le format proposé par les Eurocodes.On propose deux modèles de comportement basés sur la théorie de l’élastoplasticité à un seul mécanisme : « le modèle H1 » et « le modèle H2 », qui comportent respectivement une loi d’écrouissage isotrope et une loi d’écrouissage cinématique non linéaire. Les formulations des deux modèles sont présentées. Leurs différents paramètres sont définis à partir d’essais en laboratoire ou in situ. On étudie l’influence de chacun de ces paramètres dans le cas des essais triaxiaux.Ces deux modèles sont implémentés dans le code de calcul par éléments finis CESAR-LCPC. Une analyse numérique d’un projet réel d’excavation issu d’un exercice de prévision (benchmark) avec différents modèles de comportement est présentée. Les résultats obtenus avec le modèle H2 n’améliorent pas significativement les résultats par rapport au modèle H1. Dans la suite, on concentre la discussion sur le modèle H1. Des études paramétriques sont réalisées sur ce projet d’excavation pour identifier les paramètres qui ont une influence sur la cuvette de tassement calculée. Dans le cadre du Projet Grand Paris Express, de nouvelles lignes de métro sont en cours de réalisation. La fouille de la future gare de Créteil L’Échat de la ligne 15 sud est choisie comme cas d’étude. Les résultats numériques obtenus avec le modèle H1 sont confrontés à des mesures réalisées dans cette gare.Le dernier chapitre aborde la justification aux états limites ultimes des ouvrages de soutènement. La discussion est axée sur la procédure de réduction des propriétés de cisaillement des sols (c-phi réduction). On cherche à préciser dans quelle mesure cette méthode peut être adaptée à des modèles de comportement complexes comme le modèle H1
The present research work addresses various aspects of the numerical modelling of the displacements induced by deep excavations. The first objective is to define a constitutive model allowing to obtain a good estimation of the settlement behind the retaining wall. A second objective is to contribute to the justification of retaining structures for ultimate limit states according to the format proposed by the Eurocodes.Two constitutive models based on the theory of elastoplasticity with a single mechanism are proposed: "H1 model" and "H2 model" which include respectively an isotropic hardening law and a non-linear kinematic hardening law. The formulations of the two models are presented. Their different parameters are defined from laboratory or in situ tests. The influence of each of these parameters is studied in the case of triaxial tests.Both models are implemented in the CESAR-LCPC finite element calculation code. A numerical analysis of a real excavation project taken from a benchmark prevision exercise with different constitutive models is presented. The results obtained with the H2 model do not significantly improve the results compared to the H1 model. In the following, the discussion focuses on the H1 model. Parametric studies are carried out on this excavation project to identify the parameters that have an influence on the settlement distribution calculated behind the retaining wall. Within the framework of the Grand Paris Express Project, new metro lines are being built. The excavation of the future “Créteil L'Échat” station of line 15 south is chosen as a case study in this thesis. The numerical results obtained with the H1 model are compared with measurements obtained in this station.Regarding the justification for the ultimate limit states of retaining structures, the discussion focuses on the procedure of reduction of the shear properties of soils (c-phi reduction). We seek to clarify to what extent this method can be adapted to complex constitutive models such as the H1 model
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22

Kotheimer, Michael J. "Damage approximation in buildings adjacent to deep excavations." Ohio : Ohio University, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1175182826.

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23

Luk, Tat-fai, and 陸達輝. "Case studies on the stability of deep excavations." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31226449.

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24

Mellies, Gabriele. "TWO CASE STUDIES OF EXCAVATIONS IN FRACTURED ROCK." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26279/26279.pdf.

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La stabilité des excavations dans les roches fracturées est influencée, entre autres, par le régime structural, qui est inhérent à la roche. Divers outils sont disponibles pour les analyses de stabilité, mais la qualité des résultats dépend considérablement des données d’entrée disponibles et des outils utilisés. Dans ce mémoire, deux études de cas sont présentées, qui étudient l'influence de la représentation de données structurales sur l'analyse de stabilité. La première étude de cas traite de la stabilité d'une pente de roche le long d'une route près de Fleurimont, qui a subi des effondrements de dièdre. L’objectif était de découvrir si les effondrements pourraient avoir été prédits et d'évaluer la probabilité de la rupture de dièdre le long de la pente. Plusieurs analyses d'équilibre limite ont été effectuées, y compris une analyse déterministe rétrospective de deux ruptures de dièdres, et une analyse probabiliste des dièdres individuels. De plus, une analyse probabiliste de système de joints a été effectuée en utilisant les modèles 3D de système de joints, qui ont été générés avec des données de terrain. Les données nécessaires pour les analyses ont été recueillies sur place. Les résultats d’analyse rétrospective ont indiqué l'instabilité potentielle des dièdres observés, et les approches probabilistes ont confirmé l'occurrence des effondrements de dièdre le long de la pente, mais ils ont également démontré que la probabilité d'effondrements semblables est faible. Les résultats ont démontré qu'une analyse de données exhaustive en utilisant plusieurs outils d'analyse est requise pour obtenir une évaluation fiable du comportement de la roche. La deuxième étude de cas discute de la stabilité des galeries à la mine souterraine LaRonde de l'Agnico Eagle, qui sont concernées par de grandes déformations à cause de la convergence des parois. L'analyse de la convergence observée s'est concentrée sur la génération d'une série de modèles numériques 2D selon la méthode des éléments finis, visant à reproduire le mécanisme d'effondrement et les déformations résultantes. La foliation in situ a été reproduite par des joints, qui ont été introduits explicitement dans le modèle. Les données structurales requises ont été rassemblées sur place. Les modèles ont été calibrés avec les données de convergence disponibles. Les résultats de modélisation numérique ont atteint une bonne concordance avec les observations sur place. Les deux profils caractéristiques observés et l’ordre de grandeur des déformations mesurées ont pu être reproduits. Il a été démontré que le modèle numérique appliqué est un outil utile pour modéliser les conditions complexes observées à la mine. Plus d'expériences de validation devraient être effectuées, mais la méthode peut potentiellement être employée pour élaborer de meilleures stratégies pour les travaux de développement minier dans des conditions semblables. Les deux études de cas ont démontré l'influence de la représentation des données structurales sur l'analyse de données. En outre il a été montré que le choix des outils d'analyse influence les résultats obtenus.
The stability of excavations in fractured rock is influenced among others by the structural order inherent in the rock mass. Various analysis tools are available for stability analysis, but the quality of results depends considerably on the available analysis data and the tools used. In this thesis two case studies of excavations in fractured rock are presented that investigate the influence of structural data representation on the stability analysis. The first case study focused on the stability of a rock slope along a road cut near Fleurimont that has experienced wedge failures. The aim was to find out, if the failures could have been predicted, and to evaluate the probability of wedge failures along the slope. Different limit equilibrium wedge analyses were carried out, including a deterministic back-analysis of two wedge failures and a probabilistic analysis of individual wedges. Furthermore a probabilistic joint system analysis was carried out using 3D joint system models generated out of field data. As part of this work the required analysis data was collected on site. The back-analysis results suggested potential instability of the observed wedges, and the probabilistic approaches confirmed the occurrence of wedge failures along the slope, but also indicated the only low probability for these failures. The results demonstrated that a comprehensive data analysis using various analysis tools is required to reach a reliable assessment of the rock behaviour. The second case study discusses the stability of drifts at Agnico Eagle’s LaRonde underground mine that are affected by large deformations due to rock squeezing. The analysis of the observed drift convergence focused on the generation of a series of numerical 2D finite element models, aiming to reproduce failure mechanism and resulting deformations. The in situ foliation was reproduced by explicitly introducing joints into the model. The required structural data was collected on site. As reference data for the model calibration available convergence data was used. The modelling results reached a good agreement with the observations on site. Both observed characteristic deformation profiles as well as measured deformation magnitudes could be adequately reproduced. It could be demonstrated that the applied numerical model is a useful tool to model the complex squeezing ground conditions observed at the mine. More validation experiments should be carried out, but the method can potentially be used to develop better mine development strategies in similar conditions. Both case studies demonstrated the influence of structural data representation on the data analysis. Furthermore it could be shown that the choice of analysis tools influences the obtained results.
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25

Momigliano, Nicoletta. "MM 1A pottery from Evans' excavations at Knossos." Thesis, University College London (University of London), 1989. http://discovery.ucl.ac.uk/10048638/.

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The famous excavations of Sir Arthur Evans at Knossos produced vast quantities of ceramic material. This thesis presents a new analysis of the most important Knossian deposits assigned by Evans to the Middle Minoan IA (MM IA) phase in his system of classification of the Minoan Bronze Age. These deposits have never been systematically studied and are largely unpublished or inadequately published. The first, introductory chapter of the thesis is a short discussion of the previous studies and current definitions of Knossian MM IA pottery, of the sources of information, and of the problems involved in the study of Evans' material. Chapter 2 deals with the deposits located in the West Court, such as Houses A, B and C, etc. Chapter 3 deals with the deposits located in the area of the Palace, such as the Vat Room, the Upper East Well, etc.. Chapter 4 deals with the North Quarter of the City, a deposit from outside the area of the Palace. Chapters 2-4 present a detailed analysis of the pottery, based upon a re-examination of the relevant documentary sources (excavation notebooks etc.) and a first-hand knowledge of the ceramic material. Chapter 5 presents a typology of Knossian MM IA pottery and briefly discusses its production and decoration. The picture of Knossian MM IA pottery presented in this study is remarkably different from that of Evans. Chapter 6 discusses vases of foreign origin (and/or local imitations) found in Knossian MM IA deposits, Knossian MM IA vases Land/or local imitations) found outside the Knossos region, and the implications for relative chronology. Chapter 7 summarizes the main results obtained by this study. There is a Catalogue of the complete and restorable vases from the various deposits discussed in the text, and Appendix 1 lists various Knossian MM IA deposits, including those which could not be included in the present study.
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26

LE, LU NOURRI CHANTAL. "Contribution clinique a l'etude des grandes excavations innees." Angers, 1990. http://www.theses.fr/1990ANGE1119.

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27

Mellies, Gabriele, and Gabriele Mellies. "Two case studies of excavations in fractured rock." Master's thesis, Université Laval, 2009. http://hdl.handle.net/20.500.11794/21030.

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La stabilité des excavations dans les roches fracturées est influencée, entre autres, par le régime structural, qui est inhérent à la roche. Divers outils sont disponibles pour les analyses de stabilité, mais la qualité des résultats dépend considérablement des données d’entrée disponibles et des outils utilisés. Dans ce mémoire, deux études de cas sont présentées, qui étudient l'influence de la représentation de données structurales sur l'analyse de stabilité. La première étude de cas traite de la stabilité d'une pente de roche le long d'une route près de Fleurimont, qui a subi des effondrements de dièdre. L’objectif était de découvrir si les effondrements pourraient avoir été prédits et d'évaluer la probabilité de la rupture de dièdre le long de la pente. Plusieurs analyses d'équilibre limite ont été effectuées, y compris une analyse déterministe rétrospective de deux ruptures de dièdres, et une analyse probabiliste des dièdres individuels. De plus, une analyse probabiliste de système de joints a été effectuée en utilisant les modèles 3D de système de joints, qui ont été générés avec des données de terrain. Les données nécessaires pour les analyses ont été recueillies sur place. Les résultats d’analyse rétrospective ont indiqué l'instabilité potentielle des dièdres observés, et les approches probabilistes ont confirmé l'occurrence des effondrements de dièdre le long de la pente, mais ils ont également démontré que la probabilité d'effondrements semblables est faible. Les résultats ont démontré qu'une analyse de données exhaustive en utilisant plusieurs outils d'analyse est requise pour obtenir une évaluation fiable du comportement de la roche. La deuxième étude de cas discute de la stabilité des galeries à la mine souterraine LaRonde de l'Agnico Eagle, qui sont concernées par de grandes déformations à cause de la convergence des parois. L'analyse de la convergence observée s'est concentrée sur la génération d'une série de modèles numériques 2D selon la méthode des éléments finis, visant à reproduire le mécanisme d'effondrement et les déformations résultantes. La foliation in situ a été reproduite par des joints, qui ont été introduits explicitement dans le modèle. Les données structurales requises ont été rassemblées sur place. Les modèles ont été calibrés avec les données de convergence disponibles. Les résultats de modélisation numérique ont atteint une bonne concordance avec les observations sur place. Les deux profils caractéristiques observés et l’ordre de grandeur des déformations mesurées ont pu être reproduits. Il a été démontré que le modèle numérique appliqué est un outil utile pour modéliser les conditions complexes observées à la mine. Plus d'expériences de validation devraient être effectuées, mais la méthode peut potentiellement être employée pour élaborer de meilleures stratégies pour les travaux de développement minier dans des conditions semblables. Les deux études de cas ont démontré l'influence de la représentation des données structurales sur l'analyse de données. En outre il a été montré que le choix des outils d'analyse influence les résultats obtenus.
La stabilité des excavations dans les roches fracturées est influencée, entre autres, par le régime structural, qui est inhérent à la roche. Divers outils sont disponibles pour les analyses de stabilité, mais la qualité des résultats dépend considérablement des données d’entrée disponibles et des outils utilisés. Dans ce mémoire, deux études de cas sont présentées, qui étudient l'influence de la représentation de données structurales sur l'analyse de stabilité. La première étude de cas traite de la stabilité d'une pente de roche le long d'une route près de Fleurimont, qui a subi des effondrements de dièdre. L’objectif était de découvrir si les effondrements pourraient avoir été prédits et d'évaluer la probabilité de la rupture de dièdre le long de la pente. Plusieurs analyses d'équilibre limite ont été effectuées, y compris une analyse déterministe rétrospective de deux ruptures de dièdres, et une analyse probabiliste des dièdres individuels. De plus, une analyse probabiliste de système de joints a été effectuée en utilisant les modèles 3D de système de joints, qui ont été générés avec des données de terrain. Les données nécessaires pour les analyses ont été recueillies sur place. Les résultats d’analyse rétrospective ont indiqué l'instabilité potentielle des dièdres observés, et les approches probabilistes ont confirmé l'occurrence des effondrements de dièdre le long de la pente, mais ils ont également démontré que la probabilité d'effondrements semblables est faible. Les résultats ont démontré qu'une analyse de données exhaustive en utilisant plusieurs outils d'analyse est requise pour obtenir une évaluation fiable du comportement de la roche. La deuxième étude de cas discute de la stabilité des galeries à la mine souterraine LaRonde de l'Agnico Eagle, qui sont concernées par de grandes déformations à cause de la convergence des parois. L'analyse de la convergence observée s'est concentrée sur la génération d'une série de modèles numériques 2D selon la méthode des éléments finis, visant à reproduire le mécanisme d'effondrement et les déformations résultantes. La foliation in situ a été reproduite par des joints, qui ont été introduits explicitement dans le modèle. Les données structurales requises ont été rassemblées sur place. Les modèles ont été calibrés avec les données de convergence disponibles. Les résultats de modélisation numérique ont atteint une bonne concordance avec les observations sur place. Les deux profils caractéristiques observés et l’ordre de grandeur des déformations mesurées ont pu être reproduits. Il a été démontré que le modèle numérique appliqué est un outil utile pour modéliser les conditions complexes observées à la mine. Plus d'expériences de validation devraient être effectuées, mais la méthode peut potentiellement être employée pour élaborer de meilleures stratégies pour les travaux de développement minier dans des conditions semblables. Les deux études de cas ont démontré l'influence de la représentation des données structurales sur l'analyse de données. En outre il a été montré que le choix des outils d'analyse influence les résultats obtenus.
The stability of excavations in fractured rock is influenced among others by the structural order inherent in the rock mass. Various analysis tools are available for stability analysis, but the quality of results depends considerably on the available analysis data and the tools used. In this thesis two case studies of excavations in fractured rock are presented that investigate the influence of structural data representation on the stability analysis. The first case study focused on the stability of a rock slope along a road cut near Fleurimont that has experienced wedge failures. The aim was to find out, if the failures could have been predicted, and to evaluate the probability of wedge failures along the slope. Different limit equilibrium wedge analyses were carried out, including a deterministic back-analysis of two wedge failures and a probabilistic analysis of individual wedges. Furthermore a probabilistic joint system analysis was carried out using 3D joint system models generated out of field data. As part of this work the required analysis data was collected on site. The back-analysis results suggested potential instability of the observed wedges, and the probabilistic approaches confirmed the occurrence of wedge failures along the slope, but also indicated the only low probability for these failures. The results demonstrated that a comprehensive data analysis using various analysis tools is required to reach a reliable assessment of the rock behaviour. The second case study discusses the stability of drifts at Agnico Eagle’s LaRonde underground mine that are affected by large deformations due to rock squeezing. The analysis of the observed drift convergence focused on the generation of a series of numerical 2D finite element models, aiming to reproduce failure mechanism and resulting deformations. The in situ foliation was reproduced by explicitly introducing joints into the model. The required structural data was collected on site. As reference data for the model calibration available convergence data was used. The modelling results reached a good agreement with the observations on site. Both observed characteristic deformation profiles as well as measured deformation magnitudes could be adequately reproduced. It could be demonstrated that the applied numerical model is a useful tool to model the complex squeezing ground conditions observed at the mine. More validation experiments should be carried out, but the method can potentially be used to develop better mine development strategies in similar conditions. Both case studies demonstrated the influence of structural data representation on the data analysis. Furthermore it could be shown that the choice of analysis tools influences the obtained results.
The stability of excavations in fractured rock is influenced among others by the structural order inherent in the rock mass. Various analysis tools are available for stability analysis, but the quality of results depends considerably on the available analysis data and the tools used. In this thesis two case studies of excavations in fractured rock are presented that investigate the influence of structural data representation on the stability analysis. The first case study focused on the stability of a rock slope along a road cut near Fleurimont that has experienced wedge failures. The aim was to find out, if the failures could have been predicted, and to evaluate the probability of wedge failures along the slope. Different limit equilibrium wedge analyses were carried out, including a deterministic back-analysis of two wedge failures and a probabilistic analysis of individual wedges. Furthermore a probabilistic joint system analysis was carried out using 3D joint system models generated out of field data. As part of this work the required analysis data was collected on site. The back-analysis results suggested potential instability of the observed wedges, and the probabilistic approaches confirmed the occurrence of wedge failures along the slope, but also indicated the only low probability for these failures. The results demonstrated that a comprehensive data analysis using various analysis tools is required to reach a reliable assessment of the rock behaviour. The second case study discusses the stability of drifts at Agnico Eagle’s LaRonde underground mine that are affected by large deformations due to rock squeezing. The analysis of the observed drift convergence focused on the generation of a series of numerical 2D finite element models, aiming to reproduce failure mechanism and resulting deformations. The in situ foliation was reproduced by explicitly introducing joints into the model. The required structural data was collected on site. As reference data for the model calibration available convergence data was used. The modelling results reached a good agreement with the observations on site. Both observed characteristic deformation profiles as well as measured deformation magnitudes could be adequately reproduced. It could be demonstrated that the applied numerical model is a useful tool to model the complex squeezing ground conditions observed at the mine. More validation experiments should be carried out, but the method can potentially be used to develop better mine development strategies in similar conditions. Both case studies demonstrated the influence of structural data representation on the data analysis. Furthermore it could be shown that the choice of analysis tools influences the obtained results.
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28

Luk, Tat-fai. "Case studies on the stability of deep excavations /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23589486.

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29

Xiao, Bo. "Numerical simulation of deep excavations in rock masses." Thesis, The University of Sydney, 1994. https://hdl.handle.net/2123/26842.

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Deep excavations are widely used for various purposes in industries including civil, mining, military, petroleum, energy and environmental engineering. The number and size of excavations have increased steadily in recent years. In engineering practice, designers are particularly interesting in making accurate predictions of the magnitudes of movements in the surrounding rock masses associated with the construction activities, and the likely extent of damage to adjacent structures and facilities. It is therefore of interest to develop reliable and efficient techniques which are able to predict accurately the deformation and stress distributions around excavations in the rock masses. On the basis of both theoretical and practical considerations, this thesis attempted to develop efficient techniques for analysis and to provide a better understanding of the rock mass behaviour during excavation. Rock masses are seldom found in nature without joints or discontinuities which can have a significant effect on the gross mechanical response. In practice, it is almost impossible to explore all of the joint systems or to investigate all their mechanical characteristics. Moreover, when the spacing between the joints is small in comparison with the length scale of interest (such as tunnel width or foundation size), a simulation incorporating the jointing explicitly is very difficult and costly to implement. In these cases, the use of the equivalent continuum model to simulate behaviour of jointed rock masses could be valuable. A concept of "deformation equivalence" has been adopted to derive an equivalent continuum model for simulation of elastic behaviour of jointed rock mass. At higher levels of applied stress either the intact rock or some of the joints or both may yield, and subsequently they will behave plastically. An elastoplastic equivalent continuum model containing any finite number of joint sets in which any of the joint sets and the surrounding intact rock may undergo plastic deformation has been described. A quadratic boundary element method for an anisotropic medium has been developed. It has been demonstrated that the use of quadratic elements can yield accurate results with relatively coarse boundary element meshes, and can not only more adequately represent a curved boundary but it can also give more accurate results than constant elements. A coupled finite element and boundary element method for analysis of boundary value problems in anisotropic rock masses has been developed. This method is characterised by using equivalent continuum models to represent the rock mass as an equivalent, anisotropic, elastic or elastoplastic continuum. In this method. the presence of joints, the sequential excavation or construction, inhomogeneous materials, material non—linearities can be considered in regions of interest which can be represented numerically by a finite element mesh, and the boundary discretisation can be used to represent the response of anisotropic rock masses in the far field. The formulation has been validated by comparing available analytical solutions. In order to provide a detailed understanding of the behaviour of a jointed rock mass around excavations, numerical studies for both circular openings and deep basements excavated in jointed rock masses have been carried out. For circular openings, the predictions illustrate the effects of joint spacing and shear stiffness on the ground response curve, and the zones in the rock mass around the tunnel where intact rock has yielded plastically and where the joints have yielded in shear or have opened. Plots of the dimensionless ground response curves, the vectors of displacement and the contours of the yield ratio for tunnels at various dimensionless depths in jointed rock masses have been presented. For basement excavation problems, the numerical results illustrate the effects of anisotropy of the rock mass and the orientation and spacing of the joint sets around the excavation. I The deformation and stress distributions, the stability of rock masses around the basements and effect of dilatancy in rock joints on the movements of the rock mass have been studied. A case history of a basement excavation adjacent to railway tunnels in rock masses is also presented to demonstrate the capability of the proposed method in solving practical problems. The excavation is located in the central business district of Sydney and is approximately 30m deep with a total of about 500,000m3 of rock having been excavated. Good agreement has been found between the field measurements and numerical predictions.
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30

Haggerty, Daniel. "A Comparison of Predicted Brace Loads in Temporary Retaining Structures and Observed Brace Loads in Two Full Scale Test Sections." ScholarWorks@UNO, 2003. http://scholarworks.uno.edu/td/51.

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This thesis presents analyses of the results of a geotechnical instrumentation program performed by Eustis Engineering Company for the U.S. Army Corps of Engineers (USACE) during the construction of two covered canals in New Orleans, Louisiana. At each site, a cast-in-place concrete culvert was constructed within a sheeted and braced excavation. Information provided by Eustis Engineering Company to the USACE is presented describing the existing soil conditions, the construction schedule, the geotechnical testing apparatus and instrumentation, and the data produced from the geotechnical instrumentation program. In this thesis, several theoretical approaches available for estimating the strut loads in braced excavations were examined and used to predict the strut loads at the two construction sites. These theoretical approaches included Coulomb pressures diagrams, Terzaghi pressure diagrams, and soil-structure interaction. The results of the theoretical strut load prediction methods are presented and compared with the results of the geotechnical instrumentation program data.
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31

Bürgi, Christoph. "Cataclastic fault rocks in underground excavations : a geological characterisation /." [S.l.] : [s.n.], 1999. http://library.epfl.ch/theses/?nr=1975.

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Gumusoglu, M. Cetin. "Analysis of underground excavations in strain softening rock masses." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/38339.

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33

Ghabraie, Kazem, and n/a. "Exploring topology and shape optimisation techniques in underground excavations." RMIT University. Civil, Environmental and Chemical Engineering, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091118.135631.

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Topology optimisation techniques help designers to nd the best layout of structural members. When followed by shape and sizing optimisation, these techniques result in far greater savings than shape and sizing optimisation alone. During the last three decades extensive research has been carried out in the topology optimisation area. Consequently topology optimisation techniques have been considerably improved and successfully applied to a range of physical problems. These techniques are now regarded as invaluable tools in mechanical, aerostructural and structural design. In spite of great potential in geomechanical problems, however, the application of topology optimisation techniques in this eld has not been studied thoroughly. This thesis explores the state-of-the-art topology and shape optimisation methods in excavation design. The main problems of concern in this thesis are to nd the optimum shape of an underground opening and to optimise the reinforcement distribution around it. To tackle these problems, new formulations for some topology optimisation techniques are proposed in this thesis to match the requirements in excavation problems. Although linear elastic material models have limited applications in excavation design, these models are used in the rst part of this thesis to introduce the proposed optimisation technique and to verify it. Simultaneous shape and reinforcement optimisation is considered as well. Using the proposed optimisation techniques, it is shown that the computational effort needed for this mixed optimisation problem is almost the same as the effort required to solve each of shape or reinforcement optimisation problems alone. In the next part of this thesis, reinforcement optimisation of tunnels in massive rocks is addressed where the behaviour of the rock mass is in uenced by few major discontinuities. Although discontinuities exist in the majority of rock masses, due to its complexities, optimising the excavations in these types of rocks has not been considered by any other researcher before. A method for reinforcement optimisation of tunnels in such rock masses is proposed in this thesis and its capability is demonstrated by means of numerical examples. Lastly, shape optimisation of excavations in elasto-plastic soil is addressed. In this problem the excavation sequence is also taken into account. A stressbased parameter is dened to evaluate the efficiency of the soil elements assuming Mohr-Coulomb material model. Some examples are solved to illustrate and verify the application of the proposed technique. Being one of the rst theses on the topic, this work concentrates on the theoretical background and the possibility of applying topology optimisation techniques in excavation designs. It has been demonstrated that a properly tailored topology optimisation technique can be applied to nd both the optimum shape and the optimum reinforcement design of openings. Optimising the excavations in various types of grounds including elastic homogeneous rock masses, massive rocks, and elasto-plastic soil and rock media have been considered. Different objective functions, namely, mean compliance, oor heave, and tunnel convergence have been selected and successfully minimised using the proposed techniques. The results obtained in this thesis illustrate that the proposed topology optimisation techniques are very useful for improving excavation designs.
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Gómez-Hernández, Jairo. "A model for rock mass bulking around underground excavations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ61269.pdf.

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35

Green, Erik. "Stability and predicted ground movements of slurry trench excavations." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B30431621.

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36

Panchal, Jignasha. "Minimising ground movements around deep excavations in soft soils." Thesis, City, University of London, 2018. http://openaccess.city.ac.uk/21044/.

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This research concerns the influence of a range of construction methods, acting at or below excavation formation level, on ground movements of the retained surface attributed to a 12m deep excavation in very soft to soft soil. Movements around excavations arise as a consequence of the removal of soil and lateral wall deformations. The work examined the behaviour of excavations that were supported by a high stiffness embedded retaining wall whilst modelling a variety of construction techniques. Four distinct construction methods were modelled which could be regarded as surcharging the formation level or stiffening the ground below excavation formation level. The specific techniques that were explored include underwater excavations, bermed excavations, deep soil mixing and double walled excavations. This study aimed to determine the efficiency of these construction measures on reducing the magnitude and extent of displacements occurring behind the retaining wall. Experimental data were obtained from twenty-two plane strain centrifuge model tests undertaken at 160g. The geometry of the model comprised a pre-formed excavation where the retaining wall was laterally supported by a continuous prop acting over the majority of the height of the wall and the excavation formation level was surcharged by a pressurised rubber bag. Pressure in the bag at formation level was reduced at a constant rate to simulate the stress change caused by the excavation process. Vertical movements at the retained ground surface were measured using displacement transducers whilst subsurface deformations elsewhere in the model were determined from the analysis of digital images captured by cameras viewing the front of the model through a Perspex window. The magnitude and extent of movements were quantified and the general patterns of ground deformation were identified for the construction methods implemented. A series of reference tests were conducted to provide a baseline against which modified excavation tests were compared. The stiff wall and continuous prop supporting the retaining wall ensured that the reference tests quantified the magnitude of displacements at the retained surface arising simply as a result of heave at the formation level. The main test series investigated a range of construction methods that aimed to surcharge or stiffen the formation level. Additional tests were also undertaken to evaluate the influence of wall embedment on the performance of the excavation system. Direct comparisons were also drawn between tests in an attempt to establish the significance of wall crest fixity on soil movements. The use of all of the special construction techniques investigated were shown to reduce the magnitude of vertical displacement behind the retaining wall and at the formation level; in addition to reducing horizontal displacements at the toe of the wall. Increasing the retaining wall embedment depth in the main test series generally reduced the magnitude of vertical settlement by a factor of two, however the effect was less pronounced in the reference tests. Improving the fixity of the crest of the wall delayed excavation collapse and, where additional support mechanisms were not employed, pinning the crest of the wall was shown to reduce maximum settlement in the reference test by a factor of three. Of the four supporting construction methods the underwater excavation was found to be the most effective owing to the reduced change in vertical stress during the simulated excavation. Various deep soil mixing geometries were modelled and similar excavation behaviour was observed, however deep soil mixing ground treatment extending to the toe of the retaining wall and across 2/3 of the excavation demonstrated a slight reduction in settlement. Similar behaviour was observed for double walled excavations. Combining underwater excavations with a double wall was shown to further reduce maximum settlements however little additional benefit was observed when performing an underwater excavation with a deep soil mixed soil layer at excavation formation level.
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37

Jen, Lucy C. (Lucy Chin) 1968. "The design and performance of deep excavations in clay." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10017.

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38

Hellings, Jan Eise. "The strength and stiffness of soils associated with excavations." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47471.

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39

Li, Yixiang Li. "Numerical modeling of supported excavations considering soil spatial variability." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1510322541966921.

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40

Zghondi, Jad. "Modélisation avancée des excavations multi-supportées en site urbain." Lyon, INSA, 2010. http://theses.insa-lyon.fr/publication/2010ISAL0092/these.pdf.

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La complexité croissante des projets d’excavations profondes en site urbain ainsi que la limitation de l’impact de ces travaux sur les ouvrages avoisinants requièrent une évaluation la plus précise possible du comportement de ces ouvrages. Cette évaluation doit faire appel à des méthodes de calcul prenant en compte une connaissance limitée (en particulier en phase d’avant-projet) des différents paramètres du problème, plus particulièrement les paramètres mécaniques des sols intéressés par la réalisation de l’ouvrage. L’objectif de cette thèse est d’évaluer la pertinence de différentes approches de calcul des rideaux de soutènements multi-supportés. Elle s’appuie sur la confrontation des résultats de calcul avec ceux d’une campagne d’essais sur modèle réduit et de plusieurs excavations réelles instrumentées représentant un large panel de types de sol, de nombre et disposition des supports ainsi que de précontrainte. L’évaluation de la pertinence des approches de calcul a nécessité la définition d’une méthode d’analyse en retour précise et rigoureuse basée sur un certain nombre d’indicateurs d’erreurs (relatifs aux déformées de la paroi, aux efforts dans les supports ainsi que sur les mouvements de sol observés en surface). Cette analyse en retour a pour objectif essentiel de déterminer, pour chaque approche de calcul, les valeurs les plus représentatives des paramètres de sol qui peuvent expliquer le mieux le comportement de l’ouvrage. Les résultats obtenus montrent notamment que la loi de comportement utilisée lors d’une modélisation d’excavation, devait être au moins du niveau de complexité de la loi Hardening Soil Model (mise en œuvre dans le logiciel Eléments Finis Plaxis), pour pouvoir simuler correctement le comportement de l’excavation et que, pour qu’une démarche d’analyse en retour soit pertinente, on ne peux se contenter de la seule analyse des déformées de la paroi mais que des informations sur les efforts dans les supports sont nécessaires
The increasing complexity of deep excavation projects in urban areas and the limitation of the impact of these works on surrounding structures require the assessment of the behavior of these structures. This assessment should consider the calculation methods taking into account a limited knowledge (especially in pre-project phase) of the various parameters of the problem, especially the mechanical parameters of soils mobilized by the excavation process. The objective of this thesis is to assess the appropriateness of different approaches for the calculation of the multi-supported flexible retaining structures. It is based on the comparison of calculation results with those of a series of tests on small scale model and of several instrumented excavations representing a wide range of soil types, number and arrangement of supports and prestressing. The evaluation of the adequacy of computational approaches has necessitated the development of an accurate and thorough method of back analysis based on a number of indicators of errors (relative to the deformation of the wall, efforts in the supports and on the observed ground surface movements). The main objective of this method of back analysis is to determine, for each design approach, the most representative values of soil parameters that can best explain the behavior of the structure. The results show that the constitutive law used in numerical model of the excavation should present at least the level of complexity of the Hardening Soil Model (implemented in the FEM software Plaxis) in order to properly simulate the behavior of the excavation and that the process of back analysis is not relevant if one only considers only the deformation of the wall, but requires information on the loads in the supports
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41

De, Ambrosis Andrew. "Investigation of the facing response of soil nailed excavations." Phd thesis, Department of Civil Engineering, 2004. http://hdl.handle.net/2123/4034.

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Thesis (Ph. D.)--University of Sydney, 2005.
Title from title screen (viewed February 12, 2009). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the [Dept. of Civil Engineering], Graduate School of Engineering. Degree awarded 2005; thesis submitted 2004. Includes bibliographical references. Also available in print form.
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42

De, Ambrosis Andrew. "Investigation of the facing response of soil nailed excavations." Connect to full text, 2004. http://ses.library.usyd.edu.au/handle/2123/4034.

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Thesis (Ph. D.)--University of Sydney, 2005.
Title from title screen (viewed February 12, 2009). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the [Dept. of Civil Engineering], Graduate School of Engineering. Degree awarded 2005; thesis submitted 2004. Includes bibliographical references. Also available in print form.
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43

Çimen, Görkem. "The excavations of the P-building and the R-bath at Labraunda: Archaeology in the 1950s based on Inge Dahlén's three excavation diaries." Thesis, Uppsala universitet, Antikens kultur och samhällsliv, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-324217.

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The area which today covers the Doric House, the Roman East Bath and the Byzantine East Church at the Karian sanctuary of Zeus at Labraunda in south-western Turkey, was by Swedish archaeologists called the P-building and the R-bath during the early 1950s. The excavations of this area in 1951 and 1953 were documented in three excavation diaries by archaeologist Inge Dahlén, written in Swedish. These diaries have, however, never been published. This thesis therefore focused to analyse Dahlén’s three excavation diaries in terms of three aspects. The first aspect was to understand the archaeological work and documentation methods at Labraunda during the 1951 and 1953 excavations and consequently, determine how the archaeology functioned in practice at the site in the early 1950s. The second aspect was to present in what ways Dahlén’s diaries could contribute to the current and future excavations at the East Bath at Labraunda. The last aspect was to study Dahlén’s own archaeological interpretations which occured in the diaries. In order to present all the three aspects, the analysis and discussion on the diaries were organised into four headings: archaeological work, archaeological finds, stratigraphy and documentation methods. Studying the diaries based on these headings showed that certain improvements occurred in the diaries from 1951 to 1953. Dahlén’s excavation diaries reveal a large amount of archaeological data regarding the progress of the excavations and the numerous discoveries from the excavated areas. They need, therefore, to be taken into consideration for a better understanding of both the early and the new excavations that are being conducted at the same area.
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44

Fortin, Louis. "Geoarchaeological Investigations along the Tambo-Ilo Coast of Southern Peru." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/FortinL2008.pdf.

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45

Matkovic, Iva. "Roman settlement of Northern Bruttium : 200 B.C.-A.D. 300 /." *McMaster only, 2001.

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46

Mánica, Malcom Miguel Ángel. "Analysis of underground excavations in argillaceous hard soils : weak rocks." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/663452.

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Materiales arcillosos rígidos, que se encuentran en la zona de transición entre suelos duros y rocas blandas, están siendo considerados actualmente en varios países como la roca huésped para el almacenamiento geológico profundo de residuos nucleares de alta actividad y larga vida. Esta posibilidad a derivado en la construcción de laboratorios de investigación subterráneos (LIS), excavados en estos materiales arcillosos rígidos, para estudiar su comportamiento bajo condiciones reales de trabajo. Entre los diferentes aspectos estudiados en los LIS, el comportamiento hidromecánico de la roca huésped es el más relevante para la presente investigación. Observaciones in situ han revelado que las excavaciones inducen daño alrededor de los túneles, en la forma de redes de fracturas, contenidas dentro de una zona llamada la zona de daño de la excavación (ZDE). La ZDE se ha identificado como una de las principales causas afectando el comportamiento de las excavaciones. En este contexto, el principal objetivo de la presente investigación es la simulación numérica del comportamiento hidromecánico de excavaciones experimentales llevadas a cabo en el LIS Meuse/Haute-Marne (Francia). Para lograrlo, se desarrolló un modelo constitutivo para caracterizar la roca huésped. El modelado de estos materiales es una tarea desafiante. Estos materiales exhiben características más propias de los suelos como considerables deformaciones plásticas, dependencia con la velocidad de carga, y creep, aunque también muestran características más típicas de las rocas como un considerable reblandecimiento y deformaciones plásticas localizadas. Además, debido a su origen sedimentario, también exhiben anisotropía en propiedades como su rigidez, resistencia, y permeabilidad. Se prestó especial atención a la reproducción de la ZDE y, por lo tanto, a la simulación objetiva de deformaciones localizadas; se empleó un enfoque no local para la regularización del continuo, el cual evita la dependencia con la malla empleada. Los resultados obtenidos proporcionan importantes conclusiones respecto al comportamiento hidromecánico de estos materiales arcillosos rígidos, e indican los principales aspectos que afectan la respuesta de las excavaciones subterráneas. En particular, se demuestra la importancia de la ZDE.
Stiff clayey materials, lying in the transition between hard soils and weak rocks, are being currently considered in several countries as possible host medium for deep geological disposal of high active and long-lived nuclear waste. This possibility has led to the construction of underground research laboratories (URL), excavated in these indurated clayey materials, to study their behaviour under real working conditions. Among the very different topics addressed in the URLs, the hydromechanical behaviour of the host rock is the one that most concerns the present research. In situ observations have revealed that excavation operations induce damage around the galleries, in the form of fracture networks, contained within a zone called excavation damaged zone (EDZ). The EDZ has been identified as one of the main aspects affecting the behaviour of the excavations. In this context, the main objective of the present study is the numerical simulation of the hydromechanical behaviour of experimental excavations performed at the Meuse/Haute-Marne URL (France). For this purpose, a constitutive model has been developed to characterise the host formation. The modelling of these stiff argillaceous materials is a quite challenging task. They exhibit soil-like features like considerable plastic strains, rate-dependency, and creep, although they also show characteristics more typical of a rock such as significant softening and localised deformations. In addition, due to their sedimentary origin, they often exhibit anisotropy in properties like stiffness, strength, and permeability. Special attention has been paid to the reproduction of the EDZ and, therefore, to the objective simulation of localised deformations; a nonlocal approach has been employed for the regularisation of the continuum, avoiding the dependence on the employed mesh. The obtained results provide relevant insights into the hydromechanical behaviour of these stiff clayey materials, and they indicate the main aspects affecting the response of the underground excavations. In particular, the relevance of the EDZ has been demonstrated.
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47

Korff, Mandy. "Response of piled buildings to the construction of deep excavations." Thesis, University of Cambridge, 2013. https://www.repository.cam.ac.uk/handle/1810/244715.

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Trends in the construction of deep excavations include deeper excavations situated closer to buildings. This research provides insight into mechanisms of soil-structure interaction for piled buildings adjacent to deep excavations to be used in the design and monitoring of deep excavations in urban areas. Most methods to assess building response have originally been developed for tunnelling projects or buildings with shallow foundations. Monitoring data of the construction of three deep excavations for the North South metro Line in Amsterdam, The Netherlands have been used to validate these methods specifically for piled buildings. In all three of the Amsterdam deep excavations studied, the largest impact on the ground surface and buildings is attributed to preliminary activities instead of the commonly expected excavation stage. The in situ preliminary activities caused 55-75% of the surface settlement and 55-65% of the building settlements. Surface settlements measured behind the wall were much larger than the wall deflections and reached over a distance of 2-3 times the excavated depth away from the wall. The shape of the surface settlements found resembles the hogging shape as defined by Peck (1969). For the excavation stage only, the shape of the displacement fits the profile proposed by Hsieh and Ou (1998). Most prediction methods overestimate the soil displacement at depth. An analytical method has been established and tested for the behaviour of piled buildings near excavations. This method includes the reduction of pile capacity due to lower stress levels, settlement due to soil deformations below the base of the pile and development of negative (or positive) skin friction due to relative movements of the soil and the pile shaft. The response of piles in the case of soil displacements depends on the working load of the pile, the percentages of end bearing and shaft friction of the pile, the size and shape of the soil settlements with depth and the distribution of the maximum shaft friction with depth. A method is derived to determine the level for each pile at which the pile and soil settlement are equal. Buildings in Amsterdam built before 1900 and without basement are most sensitive to soil displacements. For all other buildings, the pile settlement depends mainly on the working load. The actual damage experienced in buildings depends also on the relative stiffness of the building compared to the soil. Cross sections in Amsterdam have been evaluated and it is concluded that the Goh and Mair (2011) method provides a realistic, although rather large range of possible modification factors for the deflection of buildings next to excavations, deforming in hogging shape. For the incidents that happened at Vijzelgracht some well known damage indicators have been evaluated.
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48

Wright, Kristine Elizabeth. "Mortuary patterning, a burial analysis from Northwest Coast archaeological excavations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0013/MQ61518.pdf.

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49

Goh, K. H. "Response of ground and buildings to deep excavations and tunnelling." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599464.

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This dissertation describes the work to develop design guidance to incorporate the influence of building stiffness in modifying the deflection ratios and horizontal strains induced by deep excavations. Using the finite element method, a multi-proposed excavation was simulated adjacent to a building, which was modelled first as an elastic beam and then as a frame structure. Parametric studies were conducted where the structural stiffness and geometry of the building were varied and the characteristics of the excavation changed. As a result of the rigorous study, new definitions of relative building stiffness have been proposed and design guidance to estimate the building modification factors are developed from which the building deflection ratios and horizontal strains may be estimated from the Greenfield condition. Furthermore, using structural analysis, methods to include the influence of frame action were also developed for framed buildings on continuous footings and on individual footings. Two new case studies were formulated and analysed in the dissertation – the response of the Singapore Art Museum under the influence of movements induced by adjacent deep excavations, and the response of the Pasir Panjang shop houses under the influence of movements induced by bored tunnelling for the new Singapore Circle Line. Other than identifying some important behaviour of building response to tunnelling- and excavation-induced movements, these case studies – together with previously complete case histories – were also used to validate the findings from the numerical study.
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50

McNamara, Andrew Martin. "Influence of heave reducing piles on ground movements around excavations." Thesis, City University London, 2001. http://openaccess.city.ac.uk/8280/.

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The research concerns the influence of piles, installed beneath deep excavations, as a means of reducing movements in the surrounding ground. The work focussed on the use of piles installed as a part of top down basement construction, a technique used in conjunction with deep excavations in urban areas. The investigations sought to explore the effectiveness of bored piles as a means of enhancing the stiffness of the soil beneath the excavation and so reducing the spread of movements to the surrounding ground. Experimental data were obtained from a series of 19 centrifuge model tests undertaken at 100g. The plane strain models consisted of a pre-formed excavation temporarily supported by fluid pressures acting at formation level and against the retaining wall. The fluid support was removed as the test proceeded and successive levels of props were advanced against the retaining wall using pressurised hydraulic cylinders as jacks. Ground movements were measured using a combination of transducers and analysis of digital images from a camera viewing the front of the model seen through the Perspex side of the model container. These systems gave ground surface, formation level and wall displacement profiles as well as overall patterns of movement. The general model behaviour was characterised in a series of datum tests. These established the magnitude of displacements generated with ground support provided by the retaining wall alone in key positions throughout the model. Following this the overall stiffness of the soil below excavation formation level was enhanced by the introduction of either one or two rows of cast in situ piles installed at distances of 3 and 6 pile diameters from the retaining wall during model making. Direct comparison was then made between the various test results. These procedures were repeated in a small number of additional tests in which the retaining wall embedment depth was reduced. The use of piles was found to reduce both horizontal movements and settlement behind the retaining wall. Maximum reductions in settlement behind the retaining wall were found to be about 55%. The influence of piles on settlement was limited to a distance of about two times the excavation depth behind the retaining wall. Maximum reductions in horizontal displacement, near to the retaining wall, were about 70%. The effectiveness of the piles in reducing ground movement diminished with increasing prop stiffness such that when lateral displacement of the retaining wall was effectively prevented maximum movements were reduced by 40% (settlement) and 50% (horizontal). The piles were found to create a general stiffening effect that reduced horizontal movement at the toe of the retaining wall and led to reductions in overall prop load. Additionally the piles provided restraint against heave movements at the excavation formation and therefore also acted in tension. As a result the soil mass around the piles tended to behave as a block. This behaviour was observed for excavations in which both one and two rows of piles were used despite the relatively discrete nature of the elements. With increasing time after completion of the excavation the block behaviour became less well defined although the effect was better maintained when the greater number of piles were used. Finite element analyses of the centrifuge models also predicted reductions in displacement when piles were modelled at excavation formation level although the magnitude of reduction was less than that observed in the centrifuge tests.
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