Letteratura scientifica selezionata sul tema "Caissons"
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Articoli di riviste sul tema "Caissons"
1
Dou, Leisi, Haitao Wang, Bin Li, Yulin Yang e Danyang Di. "Impact of Groundwater Fluctuations on the Stability of Super-Large-Diameter Caissons before and after Reinforcement". Applied Sciences 14, n. 12 (7 giugno 2024): 4971. http://dx.doi.org/10.3390/app14124971.
Testo completoAbstract (sommario):
Super-large-diameter caissons, serving as working wells for trenchless pipe jacking technology, are being extensively constructed alongside the increasing adoption of trenchless technology in urban areas. However, being regarded merely as ancillary structures, the structural stability of a caisson during both construction and operation phases are often neglected. This study, centered on the super-large-diameter caissons within the Jinshui River flood control project in Zhengzhou, China, systematically monitored the mechanical behavior of caisson structures and surface settlement during construction and operational phases. Utilizing a validated FE method, the influence of groundwater fluctuations on the structural stability of caissons during operational phases was examined. Furthermore, potential occurrences of loose soil, voids, and caisson tilting were considered. Subsequently, the applicability of permeable polymer, foam polymer, and anchor rod reinforcement techniques were evaluated, followed by an analysis of the structural stability of the caissons post reinforcement during long-term operations. The findings demonstrate the minimal horizontal displacement of and stress variation in caissons under seasonal groundwater fluctuations, without significant structural alterations. Nevertheless, the presence of loose soil, voids, and caisson inclinations may decline the caisson’s support force and bearing capacity. With the increase in non-compactness, void size, and inclination, the structural stability of caissons notably diminishes. Reinforcing loose soil with permeable polymers, filling voids with foam polymers, and utilizing anchor rods are all effective methods for strengthening caisson structures and enhancing their stability.
2
Iskander, Magued, Sherif El-Gharbawy e Roy Olson. "Performance of suction caissons in sand and clay". Canadian Geotechnical Journal 39, n. 3 (1 giugno 2002): 576–84. http://dx.doi.org/10.1139/t02-030.
Testo completoAbstract (sommario):
The use of suction caissons (suction piles) in marine environments has been increasing in the last decade. A suction caisson is a steel pipe with an open bottom and a closed top that is inserted into the ground by pumping water out of it. Pumping creates a differential pressure across the caisson's top that pushes it into place, thus eliminating the need for pile driving. There are a number of uncertainties in the design of suction caissons. First, the state of stress and soil conditions adjacent to a suction caisson differs from those around typical driven piles or drilled shafts. Second, the axial load capacity of suction caissons depends on the rate of loading, hydraulic conductivity, drainage length, as well as the shearing strength properties of the foundation material. Finally, during pullout, volume change characteristics of the surrounding soils may change the theoretical suction pressures. A review of the existing knowledge relating to the design and construction of suction caissons is presented in this paper along with the results of a laboratory study on model caissons in sand and clay. Test results indicate that the use of suction pressure for installation of caissons is a viable alternative to conventional methods. Suction was also shown to resist some axial tensile loads.Key words: suction, pile, bucket, foundation, anchor, capacity.
3
Park, Min Su, Young Taek Kim, Sangki Park e Jiyoung Min. "Interaction Analysis between Waves and Caissons by Damping Zone Effect for Installing New Caisson on Old Caisson Breakwater". Journal of Korean Society of Coastal and Ocean Engineers 34, n. 5 (31 ottobre 2022): 156–68. http://dx.doi.org/10.9765/kscoe.2022.34.5.156.
Testo completoAbstract (sommario):
The design and construction are carried out to improve the structural stability of caisson breakwaters by installing new caissons on the front or rear of old caissons. The wave forces acting on caisson are excessively calculated by the resonance of fluid existing between the old caisson and the new caisson in the numerical analysis using potential flow. In this study, we used the damping zone option in ANSYS AQWA program to analyze the wave forces acting on individual caissons according to the interaction effects between the incident wave and the caisson. By applying the damping zone option to the fluid in which resonance occurs, the wave forces acting on individual caissons were calculated by the change of damping factor. In addition, the wave force characteristics acting on individual caissons were analyzed for the different distances between caissons in the frequency domain analysis.
4
Leung, Chun Fai, e Rui Fu Shen. "Performance of gravity caisson on sand compaction piles". Canadian Geotechnical Journal 45, n. 3 (marzo 2008): 393–407. http://dx.doi.org/10.1139/t07-093.
Testo completoAbstract (sommario):
Gravity caissons were employed as part of the wharf front structures for a container port terminal in Singapore. This paper reports the movements of eight consecutive gravity caissons supported on sand compaction piles (SCPs) with highly variable lengths of penetration. It is established that the caisson movements increase with an increase in the length of the SCP, as longer SCPs are necessary when hard strata are at greater depth. The large caisson movements observed during caisson infilling and backfilling do not pose a concern because the wharf deck beams connecting adjacent caissons can be adjusted. However, the caisson movements under service loads would affect the operation of the overlying quay cranes on top of the caissons. The present field study reveals that preloading the caissons is effective in reducing the caisson movements under service loads because the observed caisson movements are insignificant during subsequent unloading–reloading of the caissons. Back-analysis using the finite element method (FEM) shows that the observed caisson movements at different construction stages can be reasonably replicated. The numerical results are also used to evaluate the caisson tilt angle, which could not be measured in the present field study. The caisson tilt is found to be independent of the length of SCPs underneath a caisson.
5
Park, Min Su, Young Taek Kim, Sangki Park e Jiyoung Min. "Time Response Analysis of Caissons by Installing New Caisson on Existing Caisson Breakwater in Irregular Wave Condition". Journal of Korean Society of Coastal and Ocean Engineers 34, n. 6 (27 dicembre 2022): 233–46. http://dx.doi.org/10.9765/kscoe.2022.34.6.233.
Testo completoAbstract (sommario):
The design and the construction were carried out by installing new caissons on the back or the front of existing caissons to increase the structural stability of caisson breakwaters. In this study, we used the ANSYS AQWA program to analyze the wave forces acting on individual caissons according to the effects of wave-structure interaction when new caissons were additionally installed on existing caisson breakwaters. The wave force characteristics acting on the individual caisson were analyzed according to the distance among caissons in frequency domain analysis. In addition, the dynamic wave force characteristics were closely examined on the basis of the frequency at which the unusual distribution of wave forces occurs in irregular wave conditions using time domain analysis.
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Park, Min Su. "Interaction Effect between Caissons by Installation of New Caisson on Existing Caisson Breakwater in Second Order Stokes Wave Condition". Journal of Korean Society of Coastal and Ocean Engineers 33, n. 6 (31 dicembre 2021): 345–56. http://dx.doi.org/10.9765/kscoe.2021.33.6.345.
Testo completoAbstract (sommario):
In order to increase the structural stability of existing caisson breakwater, the design and the construction is carried out by installation of new caissons on the back or the front of old caissons. In this study, we use the ANSYS AQWA program to analyze the wave forces acting on individual caisson according to effects of wave structure interaction when new caissons are additionally installed on existing caisson breakwater. Firstly, the wave force characteristics acting on the individual caisson were analyzed for each period (frequency) in the frequency domain. In time domain analysis, the dynamic wave force characteristics were strongly influenced by the distance between caissons on the frequency at which the unusual distribution of wave forces occurs.
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Chakrabarti, Partha, Subrata K. Chakrabarti, Adinarayana Mukkamala, Nagaraj Anavekar, Shen Qiang e M. Sri Krishna. "Design Analysis of Moored Floating Caisson System". Journal of Offshore Mechanics and Arctic Engineering 127, n. 2 (6 ottobre 2004): 75–82. http://dx.doi.org/10.1115/1.1905640.
Testo completoAbstract (sommario):
Tacoma Narrows Constructors (TNC) are building a new suspension bridge in Tacoma, close to Seattle, Washington State, USA. The new bridge is being built just south of the existing bridge mounted on two caissons. The caissons are constructed on location after the shallow draft caissons are towed to site. During the construction sequence, the mooring system for each caisson consists of two sets of 16 mooring lines. The lower 16 lines are hooked-up after the shallow draft caisson is towed from the harbor and positioned at the site. The fairlead locations for these lines are kept constant throughout the construction process. The fairlead locations for the upper 16 lines (except three lines on the East Caisson) vary based on the caisson draft. The caissons are subject to a high current from the ebb and flood tide flow in the Narrows. The new caissons are in close proximity to the existing piers and the bottom topography at the site is varying. Therefore, considerable turbulence and vortex shedding is expected in the prevailing current, which will cause current-induced dynamic forces on the caissons. This paper describes the design and analysis of this multiline mooring system for Tacoma Narrows Bridge caissons, based on the construction sequence in the floating condition. The analysis involved optimizing the anchor locations and the line pretensions, determining the dynamic motions of the caissons, the maximum line loads, and the corresponding safety factors. The paper also describes the hydrodynamic analysis for added mass, and damping, the methodology used for the nonlinear moored caisson analysis (MOTSIM), and the validation of the design tool with other similar models (e.g., STRUCAD*3D). The results of the analysis and the design of the system are discussed.
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Xiang, Qiqi, Kai Wei, Fang Qiu, Changrong Yao e Yadong Li. "Experimental Study of Local Scour around Caissons under Unidirectional and Tidal Currents". Water 12, n. 3 (27 febbraio 2020): 640. http://dx.doi.org/10.3390/w12030640.
Testo completoAbstract (sommario):
Local scour around caissons under currents has become one of the main factors affecting the safety of foundation construction and operation in coastal and offshore bridge engineering. Local scour occurs not only in the operation stage, when the caisson has settled into the sediment, but also in the construction stage, when the caisson is suspended in water. In this study, the local scour induced by unidirectional and tidal currents around settled caissons with different cross-sections (circular, square, and diamond) was experimentally investigated. Circular and square caissons were selected to investigate the difference in local scour of suspended caissons under unidirectional and tidal currents. The main findings from the experimental results were: (1) the temporal development of scour under tidal current was slower than that of unidirectional current; (2) the effect of current type can significantly influence the size and location of maximum scour depth around circular and square caissons; (3) the appropriate choice of cross-section could reduce the maximum scour depth around the settled caisson; (4) the maximum scour depth of tidal current was smaller than that of unidirectional current when the caisson was settled into the sediment, while the opposite effect occurred when the caisson was suspended in water.
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Xu, Chenggen, Haitao Jiang, Mengtao Xu, Decheng Sun e Shengjie Rui. "Calculation Method for Uplift Capacity of Suction Caisson in Sand Considering Different Drainage Conditions". Sustainability 15, n. 1 (27 dicembre 2022): 454. http://dx.doi.org/10.3390/su15010454.
Testo completoAbstract (sommario):
Uplift capacity of suction caissons is one of the main concerns in the design of jackets with multi-caissons supported offshore wind turbine. The uplift movement of suction caissons leads to soil stress variation and increases the difficulty to predict the uplift capacity. In this paper, a calculation method considering soil stress release and differential pressure contribution is proposed to predict the uplift capacity of caisson. Firstly, a series of numerical simulations based on the SANISAND model are conducted to study the uplift responses of suction caisson in sand, and it is verified with centrifuge test results. Considering the soil drainage condition during caisson being pulled out, the fully drained, partially drained and undrained are divided, and an equation is provided to assess differential pressure beneath the caisson lid incorporating the effects of main factors. Based on the above simulation results, a calculation method is proposed to calculate the uplift capacity of caissons. The prediction results are compared with the centrifuge model tests and previous studies, which indicate that the prediction accuracy is much improved. This proposed method contributes to the more accurate assessment of uplift capacity of suction caisson in sand.
10
Zhang, Ji Cheng, e Jun Yang. "Reliability Analysis on Construction Course of Open Caisson Structure". Applied Mechanics and Materials 166-169 (maggio 2012): 1976–80. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.1976.
Testo completoAbstract (sommario):
The numerical model was established using ANSYS software, which took the interaction effect of subsoil and structure into account, the soil was considered as discrete spring elements. The soil’s mechanic parameters were set as random variable, probability analysis was performed on typical construction course of open caisson by Monte-Carlo method, the distribution rule of displacement random variables and their sensitivity to variable factors were studied, and the influence of uncertain factors on open caisson’s sinking attitude was investigated. The analysis model showed good practical value for controlling construction course of open caissons.
Tesi sul tema "Caissons"
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Ulvestad, Anders. "Consolidation Settlement of Suction Caissons". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bygg, anlegg og transport, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19504.
Testo completoAbstract (sommario):
Consolidation settlement analysis is an essential part of the design process for suction caissons. However it is a complex task since soil volume important for settlement analyses is directly affected by the installation process. Consolidation settlements have been found to be the critical design criterion in several subsea developments, adequate and correct analysis is therefore vital. The FEM code PLAXIS has been used to evaluate the reconsolidation process after completed installation of the suction caisson. Emphasize has been placed on studying the shear strength increase with time along the skirt walls. During consolidation dissipation of excess pore pressures result in higher effective stresses. Consequently the modeled undrained shear strength increases. However the increase is small compared to the expected increase in shear strength due to the set-up phenomenon. To account for the deviation an adjusted simulation procedure incorporating incremental increase of friction angle in the interface zones has been suggested. The results were found to be reasonable with respect to final consolidation settlements and development of mobilized shear strength with time.Adequate modeling of the changes in the interface zones adjacent to the caisson walls during consolidation is vital for correct prediction of long term settlements. Modeled undrained shear strength with time have huge impact on the analysis results due to different mobilization of the surrounding soil. Appropriate evaluation of soil structure interaction is essential to assess the reliability of the analysis. Taking into account changes of the soil volume important for settlement analysis is also vital. A simple physical model test has been performed. Due to delays and relatively short test period the results were inconclusive. However the importance of considering short term set-up effects has been underlined by recorded resistance and physical observations in the field.
2
Pinna, Rodney. "Buckling of suction caissons during installation". University of Western Australia. School of Civil Engineering, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0008.
Testo completoAbstract (sommario):
Suction caissons are a foundation system for offshore structures which offer a number of advantages over traditional piled foundations. In particular, due to the method of installation used, they are well suited for deep-water applications. The suction caisson consists of an open ended cylindrical shell, which is installed below the seabed in a sequence which consists of two loading phases. The caisson is first installed part way under self weight, with the installation being completed by lowering the pressure within the cylinder and thus allowing the ambient water pressure to force the caisson into the ground. This thesis examines a number of structural issues which result from the form of the caisson — essentially a thin walled cylinder — and the interaction of the caisson with the surrounding soil during installation. To do this, variational analysis and nonlinear finite element analysis are employed to examine the buckling and collapse behaviour of these cylinders. In particular, two issues are considered; the influence of the open end, and the interaction between the cylinder and soil on the buckling and collapse loads. First, the behaviour of open ended cylinders is considered, where the boundary condition at the open end is allowed to vary continuously from completely free to pinned, by the use of a variable lateral spring. This lateral spring restraint may be considered to represent the intermediate restraint provided by a ring stiffener which is not fully effective. The effect of various combinations of boundary conditions is accounted for by the use of a multiplier on the lower bound to the buckling load of a cylinder with classical supports. The variable spring at the open end may also be considered to be an initial, simple representation of the effect of soil restraint on the buckling load. More complex representations of the soil restraint are also considered. A nondimensional factor is proposed to account for the influence of this spring on the buckling load. One combination of boundary conditions, where the upper end of the caisson is pinned, and the lower end free (referred to as a PF boundary condition), is found to have buckling and collapse behaviour which is unusual for cylindrical shells. Buckling loads for such shells are much lower than would be found for cylinders with more typical boundary conditions, and of similar dimensions. More unusually however, PF cylinders are shown to have positive postbuckling strength. The behaviour is found to be a result of the large flexibility which results from the low restraint provided by the PF boundary conditions. This is shown by continuously decreasing the flexibility of the cylinder, by increasing the axial restraint at the pinned end. It is shown that this results in a large increase in buckling load, and a return to more usual levels of imperfection sensitivity. In particular, with an intermediate level of axial restraint, buckling loads and imperfection sensitivity are intermediate between those of PF shells with no, and with full, axial restraint. Overall however, collapse loads for PF cylinders with no additional restraint are well below those of cylinders with stiffer boundary conditions, for equal geometries. Eigenvalue buckling of cylinders fully and partially embedded in an elastic material are examined, and two analytical solutions are proposed. One of these is an extension of a method previously proposed by Seide (1962), for core filled cylinders, to pin ended cylinders which have support from both a core and a surrounding material. The second method represents the elastic support as a two parameter foundation. While more approximate than the first method, this method allows for the examination of a wider range of boundary conditions, and of partial embedment. It is found that the buckling load of the shell/soil system decreases as the embedment ratio decreases. Collapse of fully and partially embedded cylinders is also examined, using nonlinear finite element analysis. The influence of plasticity in the soil is also considered. For cylinders with small imperfections, it is found that the collapse load shows a large increase over that of the same cylinder with no soil support. However, as the size of initial geometric imperfections increases, it is found that the collapse load rapidly approaches that of the unsupported cylinder. In particular, in weak soils the gain in strength over the unsupported shell may be minimal. The exception to this is again PF cylinders. As these have relatively low collapse loads, even very weak soils are able to offer an increase in collapse load over the unsupported case. Finally, a summary of these results is provided in the form of guidance for design of such structures.
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Byrne, Byron Walter. "Investigations of suction caissons in dense sand". Thesis, University of Oxford, 2000. http://ora.ox.ac.uk/objects/uuid:64c30b2e-155c-4642-9115-5e2bf5667af5.
Testo completoAbstract (sommario):
Offshore structures are used in a variety of applications ranging from the traditional oil and gas extraction facilities to emerging renewable energy concepts. These structures must be secured to the seabed in an efficient and cost effective manner. A novel approach is to use shallow inverted buckets as foundations, installed by suction, in place of the more usual piles. These foundations lead to cost savings through reduction in materials and in time required for installation. It is necessary to determine how these foundations perform under typical offshore loading conditions so that design calculations may be developed. This thesis presents experimental data from a comprehensive series of investigations aimed at determining the important mechanisms to consider in the design of these shallow foundations for dense sand. Initially the long term loading behaviour (e.g. wind and current) was investigated by conducting three degree of freedom loading {V:M/2R:H} tests on a foundation embedded in dry sand. The results were interpreted through existing work-hardening plasticity theories. The analysis of the data has suggested a number of improved modelling features. Cyclic and transient tests, representing wave loading, were carried out on a foundation embedded in an oil saturated sand. The novel feature of the cyclic loading was that a 'pseudo-random' load history (based on the 'NewWave' theory) was used to represent realistic loading paths. Of particular interest was the tensile load capacity of the foundation. The results observed suggested that for tensile loading serviceability requirements rather than capacity may govern design. Under combined-load cyclic conditions the results indicated that conventional plasticity theory would not provide a sufficient description of response. A new theory, termed 'continuous hyperplasticity' was used, reproducing the results with impressive accuracy. Surprisingly, under the conditions investigated, loading rate was found to have a negligible effect on response.
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Chen, Wen. "Uniaxial behaviour of suction caissons in soft deposits in deepwater". University of Western Australia. School of Civil and Resource Engineering, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0136.
Testo completoAbstract (sommario):
Suction caissons are a cost-effective alternative to traditional piles in deep to ultradeep waters. No design rule has been available on the axial capacity of suction caissons as part of the mooring system in soft sediments. In this research, a series of centrifuge tests were performed using instrumented model caissons, to investigate the axial capacity and radial stress changes around caissons during installation, consolidation and vertical pullout in normally consolidated, lightly overconsolidated and sensitive clays. Total pressure transducers instrumented on the caisson wall were calibrated for various conditions. The radial total stress acting on the external wall varied almost linearly during penetration and extraction of the caisson, with smaller gradients observed during post-consolidation pullout. Minimum difference was found in the penetration resistance and the radial total stress for caissons installed by jacking or by suction, suggesting that the mode of soil flow at the caisson tip is similar under these two types of installation. Observed soil heave showed that the soil particles at the caisson tip flow about evenly outside and inside the caisson during suction installation. Comparison was made between measurements and various theoretical predictions, on both the radial stress changes during caisson installation, and the radial effective stress after consolidation. Significant under-predictions on excess pore pressure changes, consolidation times and external shaft friction ratios were found for the NGI Method, based on the assumption that the caisson wall is accommodated entirely by inward motion of the clay during suction installation. Obvious over-predictions by the MTD approach were found in both stress changes and shaft capacity of the caissons. A simple form of cavity expansion method was found to give reasonable estimations of stress changes and post-consolidation external shaft friction. A model for predicting the penetration resistance of suction caissons in clay was evaluated. Upper and lower bound values of external shaft friction ratio during uplift loading after consolidation were derived. Uplift capacity of caissons under sustained loading and cyclic loading were investigated, revealing approximately 15 to 30% reduction of the capacity compared to that under monotonic loading. External shaft friction ratios and reverse end-bearing capacity factors were both found to be significantly lower than those under monotonic loading
5
McKenna, Janice Elizabeth. "Wave forces on caissons and breakwater crown walls". Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263464.
Testo completo
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Ropert, François. "Modélisation numérique du comportement hydraulique des caissons Jarlan". Compiègne, 1999. http://www.theses.fr/1999COMP1203.
Testo completoAbstract (sommario):
Parmi l'ensemble des ouvrages verticaux soumis à la houle, les caissons Jarlan représentent le type de structure le plus fréquemment construit en France au cours des trois dernières décennies. Ces ouvrages sont le siège de phénomènes hydrauliques complexes, ce qui rend leur dimensionnement particulièrement délicat, notamment sous l'influence des houles obliques. L'objet du présent travail est de proposer une modélisation, par la méthode des éléments finis, des phénomènes les plus pertinents, visant à déterminer à chaque instant l'allure du plan d'eau dans le voisinage immédiat de l'ensemble des parois compo-sant l'ouvrage, afin de pouvoir calculer dans une phase ultérieure, les efforts locaux et glo-baux s'exerçant sur la structure. Deux modèles numériques bidimensionnels verticaux et un modèle bidimen-sionnel horizontal ont été développés pour couvrir l'ensemble des phénomènes à traiter. Il s'agit de modèles stationnaires travaillant avec une houle monochromatique. Les phénomènes de perte de charge et de dissipation induites par la pré-sence des perforations sont prises en compte à travers leur influence globale, moyennée sur une période et quantifiée en termes de consommation de flux d'énergie. L'exploitation du modèle horizontal, qui est couplé à un modèle classique de Berkhoff a nécessité la formulation de nouvelles conditions aux limites pour les frontières ouvertes, notamment en raison du caractère multidirectionnel de la réflexion des ouvrages composés de caissons Jarlan. Les modèles numériques ont été validés sur la base de résultats obtenus lors d'essais en modèles réduits physiques, en particulier ceux de l'Université du Havre et ceux réalisés à la SOGREAH conçus précisément à cette fin.
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Supachawarote, Chairat. "Inclined load capacity of suction caisson in clay". University of Western Australia. School of Civil and Resource Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0188.
Testo completoAbstract (sommario):
This thesis investigates the capacity and failure mode of suction caissons under inclined loading. Parametric finite element analyses have been carried out to investigate the effects of caisson geometry, loading angle, padeye depth (i.e. load attachment point), soil profile and caisson-soil interface condition. Displacement-controlled analyses were carried out to determine the ultimate limit state of the suction caissons under inclined load and the results presented as interaction diagrams in VH load space. VH failure interaction diagrams are presented for both cases where the caisson-soil interface is fully-bonded and where a crack is allowed to form along the side of the caisson. An elliptical equation is fitted to the normalised VH failure interaction diagram to describe the general trend in the case where the caisson-soil interface is fully-bonded. Parametric study reveals that the failure envelope in the fully-bonded case could be scaled down (contracted failure envelope) to represent the holding capacity when a crack is allowed to form. A stronger effect of crack on the capacity was observed in the lightly overconsolidated soil, compared to the normally consolidated soil. The sensitivity of caisson capacity to the changes in load attachment position or loading angle was quantified based on the load-controlled analyses. It was found that, for caisson length to diameter ratios of up to 5, the optimal centreline loading depth (i.e. where the caisson translates with no rotation) is in the range 0.65L to 0.7L in normally consolidated soil, but becomes shallower for the lightly overconsolidated soil profile where the shear strength profile is more uniform. The reduction of holding capacity when the padeye position is shifted from the optimal location was also quantified for normally consolidated and lightly overconsolidated soil profiles at loading angle of 30 [degrees]. Upper bound analyses were carried out to augment the finite element study. Comparison of holding capacity and accompanying failure mechanisms obtained from the finite element and upper bound methods are made. It was found that the upper bound generally overpredicted the inclined load capacity obtained from the finite element analyses especially for the shorter caisson considered in this study. A correction factor is introduced to adjust the upper bound results for the optimal condition. Comparisons of non-optimal capacity were also made and showed that the agreement between the upper bound and finite element analyses are sensitive to the change in the centreline loading depth when the caisson-soil interface is fully bonded, but less so when a crack forms.
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Senders, Marc. "Suction caissons in sand as tripod foundations for offshore wind turbines". University of Western Australia. School of Civil and Resource Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0163.
Testo completoAbstract (sommario):
[Truncated abstract] The demand for offshore wind turbines is increasing in densely populated areas, such as Europe. These constructions are typically founded on a gravity foundation or a large 'mono pile'. Gravity foundations can only be used at locations where strong soils exist and water depths are limited. Costs associated with a 'mono pile' type foundation contribute to a very large percentage of the total investment costs. This research, therefore, focuses upon a different foundation for offshore wind turbines, namely suction caissons beneath a tripod. This foundation can be used in all kinds of soil types and is cheaper than the 'mono pile' foundation, both in the amount of steel used and installation costs. Cheaper foundations can contribute to a more competitive price for offshore wind energy in comparison with other energy resources. To date, there have been relatively few studies to investigate the behaviour of this type of foundation during the installation process and during operational and ultimate loading for seabed conditions comprising dense sand. Two types of investigations were performed during this research to determine the behaviour of suction caissons beneath a tripod. Firstly, an existing computer program was extended to predict the typical loading conditions for a tripod foundation. Secondly, centrifuge tests on small scale suction caissons were performed to investigate the behaviour during the installation and loading phases. The computer program developed helped to quantify the likely ranges of environmental loading on an offshore wind turbine. For a typical 3 MW wind turbine of 90 m height, the vertical load is low at around 7 MN. During storm conditions the horizontal hydrodynamic load can be in the order of 4 MN. During normal working conditions the horizontal aerodynamic loads can reach 0.4 MN, but can increase to 1.2 MN when the pitch system malfunctions and gusts reach 30 m/s. This aerodynamic load will result in a very large contribution to the overturning moment, due to the high action point of this load. When the wind turbine is placed on top of a tripod, these large moments are counteracted by a push-pull system. ... The development of differential pressure was found to depend on the soil permeability, the extraction speed and a consolidation effect. During cyclic loading no obvious signs of a decrease in resistance were observed. During very fast cyclic loading differential pressures developed, which could increase the drained frictional resistance by approximately 40%. All centrifuge tests results were used to develop methods to predict or back calculate the installation process of suction caissons in sand and layered soil, and the behaviour during tensile and cyclic loading. These methods all use the cone resistance as the main input parameter and predict the force (or required suction) as a function of time, for a given rate of pumping or uplift displacement, in addition to the variation of suction with penetration (or force with uplift displacement). These new methods provide a useful tool in designing a reliable foundation for offshore wind turbines consisting of a tripod arrangement of suction caissons embedded in dense sand.
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Sgardeli, Christina G. (Georgia-Chrysouli C. ). "A finite element analysis of the pullout capacity of suction caissons in clay". Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53111.
Testo completoAbstract (sommario):
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2009.Includes bibliographical references (leaves 90-92).
Suction caissons are increasingly becoming the foundation of choice for offshore structures in deep water. They are used extensively in Tension Leg Platforms and provide the most efficient foundations for many offshore wind turbine structures. One of their major advantages is the ability to withstand large uplift forces by mobilizing shear on their external and internal surface and by the suction forces induced in the enclosed soil plug. These suction forces can be relied upon for short-term loading, while the behaviour of the soil remains undrained, but are more questionable for the sustained loading induced by storms and loop currents. This study uses finite element analysis to investigate the uplift capacity of suction caissons under three loading conditions: a) short-term undrained loading, b) long-term drained loading and c) sustained loading for short and long periods of time. The study compares the capacity from 5 different geometries with length to diameter ratios, L/d = 0.5,0.65,1,2 and 3 under these three loading conditions. For the sustained loading case, a minimum time under which the load can be sustained is established for different load levels. The commercial finite element program Plaxis is used and a Mohr-Coulomb model is assumed for the soil. Comparisons are presented between the results of this study, the theoretical Mohr-Coulomb model predictions and other finite element analysis found in the research for undrained and drained loading.
by Christina G. Sgardeli.
M.Eng.
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Seigneurin, Alain. "Instabilité de structures formées de plaques orthotropes (écrasement de caissons en carton ondulé)". Bordeaux 1, 1988. http://www.theses.fr/1988BOR10547.
Testo completoAbstract (sommario):
On etudie l'instabilite d'un caisson soumis a la compression en utilisant l'analyse lineaire au second ordre. La structure est supposee formee de quatre plaques, ce qui necessite une parfaite connaissance du type de liaison permettant leur assemblage. La principale modelisation decrite dans cette etude est basee sur la resolution des equations d'equilibre, etude classique qui permet une approche analytique du probleme. On n'a pu mener cette etude qu'en ayant prealablement effectue les essais mecaniques caracterisant le materiau constitutif (le carton ondule). Celui-ci est suppose dans une premiere approche homogene et orthotrope
Libri sul tema "Caissons"
1
Lawrence, Donald. Kayaks and caissons. Kamloops, B.C: Kamloops Art Gallery, 2003.
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Lawrence, Donald. Donald Lawrence [kit]: Kayaks and caissons. Kamloops, B.C: Kamloops Art Gallery, 2003.
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Burg, R. G. High-strength concrete in massive foundation elements. Skokie, Ill: Portland Cement Association, 1999.
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(Japan), Doboku Kenkyūjo. Kisetsu kēson kiso no shūkyoku jōtai to henkei seinō ni kansuru kyōdō kenkyū hōkokusho. Tsukuba-shi: Doboku Kenkyūjo, 2011.
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Hagood, Johnson. Caissons go rolling along: A memoir of America in Post-World War I Germany. Columbia, S.C: University of South Carolina Press, 2010.
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A, Grant Larry, a cura di. Caissons go rolling along: A memoir of America in post World War I Germany. Columbia, S.C: University of South Carolina Press, 2010.
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Soudy, Ibrahim R. Nonlinear dynamic analysis of caisson-type offshore structures. Edmonton, Alta., Canada: Dept. of Civil Engineering, University of Alberta, 1989.
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N, Baker Clyde, American Society of Civil Engineers. Geotechnical Engineering Division. e ASCE National Convention (1985 : Denver, Colo.), a cura di. Drilled piers and caissons II: Construction under slurry/nondestructive integrity evaluation/load testing/geotechnical behavior under load : proceedings of a session. New York, N.Y: ASCE, 1985.
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Ferrat, Stéphanie. Caisson. Bruxelles: La Lettre Volée, 2009.
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Duet, Daniel. Les caisses d'épargne. 3a ed. Paris: Presses universitaires de France, 1995.
Cerca il testo completoCapitoli di libri sul tema "Caissons"
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Jia, Junbo. "Suction Piles/Caissons". In Soil Dynamics and Foundation Modeling, 655–68. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-40358-8_26.
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Duncan, Chester I. "Piles, Piers, and Caissons". In Soils and Foundations for Architects and Engineers, 150–208. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5417-2_8.
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Duncan, Chester I. "Piles, Piers, and Caissons". In Soils and Foundations for Architects and Engineers, 137–77. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4757-6545-8_6.
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Shiraishi, S. "Unmanned excavation systems in pneumatic caissons". In Developments in Geotechnical Engineering, 409–18. London: CRC Press, 2021. http://dx.doi.org/10.1201/9781003211013-35.
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Sheil, Brian, Ronan Royston e Byron Byrne. "Real-Time Monitoring of Large-Diameter Caissons". In Springer Series in Geomechanics and Geoengineering, 725–29. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-97112-4_162.
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Sekar, Preethi, N. Preetham Rajan e Satya Kiran Raju Alluri. "Analysis of Suction Caissons in Soft Clay". In Lecture Notes in Civil Engineering, 505–16. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6370-0_45.
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Fundora Campos, Sila M., e Shin-ichi Aoki. "Effect of Horizontal Plates on the Sliding of Breakwater Caissons". In Advances in Automation, Mechanical and Design Engineering, 347–61. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-40070-4_28.
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Muni Reddy, M. G., S. Neelamani, S. A. Sannasiraj e R. Natarajan. "Effect of Offhsore Low-Crested Barrier in Reduction of Wave Pressures on Caissons". In Advances in Water Resources and Hydraulic Engineering, 1319–23. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-89465-0_231.
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Kumar, Mohit, e Kaustav Chatterjee. "A Comparative Study on Various Codes and Current Practices for Design of Caissons". In Lecture Notes in Civil Engineering, 355–66. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-0886-8_29.
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Gooch, Jan W. "Caisson". In Encyclopedic Dictionary of Polymers, 108. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_1807.
Testo completoAtti di convegni sul tema "Caissons"
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Nabipour, Mahmood, Mostafa Zeinoddini e Mahmood R. Abdi. "Failure Modes of Tapered Suction Caissons Under Vertical Pull-Out Loads". In ASME 2007 26th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2007. http://dx.doi.org/10.1115/omae2007-29490.
Testo completoAbstract (sommario):
The pull-out performance of conventional upright suction caissons has been investigated by different researchers. However, no attention has been formerly paid to tapered suction caissons. Some numerical studies already conducted by the authors demonstrated that tapered caissons exhibit pull-out capacities well above than that from their corresponding upright caissons. This paper deals with different failure mechanisms of tapered suction caissons and discusses some reason for their superior performance. A numerical approach has been used and different combinations of caisson types/ soil categories have been examined. With tapered suction caissons two different modes of failure have been discerned. The first mode has been noticed to develop in weak clays and sands under drained conditions. This mode corresponds to a shear sliding failure in the soil plug along the caisson’s interior wall. Concurrently a soil wedge is formed in the soil body adjacent to the caisson. The second mode of failure has been observed in higher strength drained clays and undrained clays and sands. With this failure mode a local failure at the bottom of the soil plug has been noticed to happen. At the same time the failure is extended to the lower surfaces of a soil wedge outside of the caisson. The detached soil plug accompanies the caisson in its movement upward following the local failure.
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Mostafa, Omar, Mohamed G. Arab e Maher Omar. "3D Finite Element Modeling of Suction Caissons Used as Foundations for Offshore Wind Turbines in Clayey Soils". In International Symposium on Engineering and Business Administration. Switzerland: Trans Tech Publications Ltd, 2023. http://dx.doi.org/10.4028/p-pxxxu9.
Testo completoAbstract (sommario):
In this study, three-dimensional finite element modeling is utilized to simulate suction caisson foundations used for offshore wind turbines. The behavior of suction caissons in normally consolidated clayey soil subjected to lateral loading is investigated. A numerical model is calibrated and validated using experimental laboratory physical model. A parametric study is conducted to evaluate the effect of suction caisson diameter (D) and the ratio of skirt length (L) to caisson diameter (L/D) on the load-deflection response of a full-scale suction caisson. Several caisson diameters and length to diameter ratios were considered. The results of numerical analysis modeling demonstrated that the caisson ultimate load capacity and displacement are significantly affected by caisson geometry. Generally, increasing both the caisson diameter and length has substantially increased both caisson’s ultimate load capacity and displacement at failure. However, the increase in ultimate capacity and displacement reaches a threshold after which the increase in these values is less pronounced as D and L/D are further increased. Additionally, the effect of caisson geometry on relative stiffness is investigated. The relative stiffness of the suction caisson was found to increase proportionally with the increase of both diameter and length of the modeled caissons.
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Zeinoddini, Mostafa, Mahmood Nabipour e Mahmood R. Abdi. "Modes of Failure for Suction Caissons Under Vertical Pull-Out Loads". In 25th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/omae2006-92239.
Testo completoAbstract (sommario):
Suction caissons have a fair base in the offshore industry, however, prediction of their behaviour and capacities still need extra attentions. Understanding their modes of failure is crucial for any analytical solutions. In this paper, failure mechanisms noticed in a numerical study of the suction caissons behaviour under vertical pull-out loading are reported. The employed finite element models have been calibrated by and verified against different available experimental data. In principal four distinctive modes of failure have been recognized. The first mode corresponds to a shear sliding failure in the soil plug along the caisson’s wall interior. This mode of failure has been mainly found in drained but comparatively weak soils. The second mode of failure noticed under drained conditions in soils with enhanced strength characteristics is a local tension failure occurring in the bottom of the soil plug. In this case the detached soil plug accompanies the caisson in its movement upward. The third mode corresponds to a restricted shear failure outside the caisson. It develops to a local wedge initiating halfway through the caisson walls and extending out to the soil surface. This failure mode has been mostly noticed with clays under undrained conditions. The foruth mode has been found to be a general shear failure in the soil underneath and around the caisson. It occurs in a wider spread body of the soil and has been noticed with the undrained sands. The load-displacement curves present a virtually bi-linear behaviour.
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Chakrabarti, Subrata K., e Mark McBride. "Current Forces on a Large Pier Near an Existing Pier". In ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51259.
Testo completoAbstract (sommario):
A new suspension bridge is being built over the Tacoma Narrows, Washington. The bridge will be placed on a structure mounted on 2 large concrete caissons, which will be exposed to strong currents. The piers are of rectangular section with chamfered edges in the upper portion. The caissons are being built at site while floating and moored in high currents. There are no known analytical methods or experimental data available on such structures at high Reynolds number. In order to determine the forces on the caisson due to current, a series of scaled physical model tests of one of the caissons was carried out. The forces on the new caisson were measured in the presence of the existing bridge pier and the bottom contours of the Narrows were accurately modeled. The model scale was chosen as 1:100 and the tests were performed for the caisson at different drafts. This paper describes the test setup, and measurement system for a series of fixed caisson tests and demonstrates the consistency of the test data. The measured inline drag and transverse lift forces on the fixed caisson at different drafts are presented and the effect of the fluid velocity and flow vorticity on the frequency contents in the forces is discussed. The interaction effect of the neighboring existing pier on the current forces of the new caisson is investigated. Since the measured forces were applied in the design analysis of the caissons, the scaling effect of the model test is also discussed. This paper is accompanied by two other papers, which form a group of three papers related to the project describing the current excitation on the caisson and the associated caisson responses. The other two papers in succession are ref. [1] and ref. [2]. The paper in ref. [1] describes the numerical computation of the current forces on the caisson by a 3-D CFD analysis, while the ref. [2] uses the information from these two papers to determine the motion response of the caissons and the mooring line tensions.
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Kakasoltani, Siamak, Mostafa Zeinoddini, Mahmoud R. Abdi e Seyyed Abbas Mousavi Behnam. "On Penetration of Upright and Tapered Suction Caissons in Sand: An Experimental Study". In ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-20499.
Testo completoAbstract (sommario):
Over the past two decades, suction caissons have been increasingly utilized as deep water anchors for floating structures, foundations of offshore wind turbines and even for jacket platforms. They penetrate into the sea bed by a combination of their buoyant weight and under base suction. Suction caissons have appeared as an efficient and economic alternative for foundations in the offshore industry. This concept, however, is relatively new, so the knowledge about their behavior has not yet gone far deep as that for other offshore foundation solutions such as driven pile systems. This paper reports some results from an experimental investigation into the installation of upright and tapered suction caissons. The 1g experiments have been carried out on eight small scale suction caissons. The aspect ratios, (the caisson length/its diameter) have been 1, 2, 3 and 4. The diameter has been constant and equal to 80 mm. Four specimens have had upright walls while the other four had a positive wall slope of 10%. The caissons have been installed in a soil tank containing very fine saturated silty sand. The penetration has been achieved under forced driving using a constant penetration rate. The effects of geometrical parameters and the soil density on the overall penetration force have been studied. it has been observed that, with both the upright and tapered caissons, the required force for full penetration increases by an increase in the aspect ratio. The penetration force required for full penetration of tapered models, has been two to three times higher than an equivalent upright caisson. With tapered caissons, the penetration forces have been found to be more sensitive to the soil density as compared to that with upright caissons. The experimental results for upright suction caissons have also been compared with a closed form analytical solution proposed by other researchers.
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Zeinoddini, Mostafa, Woorya H. Shariati e Mahmood Nabipour. "Tapering Effects on the Installation of Suction Caissons in Clay". In ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57583.
Testo completoAbstract (sommario):
This paper reports results from an investigation on the tapering effects on the installation and pull-out performance of suction caissons. A numerical finite element approach has been used for the study. The finite element models have first been calibrated/verified against several available experimental data for the installation of the upright suction caissons in clay. The verified models have then been used to examine the behaviour of the tapered suction caissons during the pull-out and installation phases. Numerical results indicate that tapered caissons present considerable enhancement in their pull-out capacity comparing to those from corresponding upright caissons. Also it has been noticed that in general tapered caissons of positive wall slopes need extra forces, in comparison to their equivalent upright caissons, to achieve a full penetration. However, at least with those models studied, these extra forces have found to be less than twenty five percent when the wall slope varies from zero (upright) to 15%. This is while the additional pull-out capacities that might be achieved from these tapered suction caissons could reach to several hundred percents. An almost linear relationship has been observed between the total installation force and the caisson’s wall slope.
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Chakrabarti, Partha, Subrata K. Chakrabarti, Adinarayana Mukkamala, Nagaraj Anavekar, Shen Qiang e M. Sri Krishna. "Design, Analysis and Verification of Moored Floating Caisson System". In ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51234.
Testo completoAbstract (sommario):
Tacoma Narrows Constructors (TNC) is building a new suspension bridge in Tacoma, close to Seattle, Washington State, USA. The new bridge will be built just south of the existing bridge mounted on two caissons, referred to as East Caisson (Tacoma side) and West Caisson (Gig Harbor side). Each pier is about 80’ wide and 130’ long in plan. The mooring system for each caisson consists of two sets of mooring lines: lower and upper. Each set consists of 16 mooring lines. The lower 16 lines consist of anchors that form a radius of about 300 feet. The fairlead locations for these lower 16 lines are kept constant throughout the construction process. These 16 lines are hooked-up after the caisson is towed from the harbor and positioned at the site. For the upper 16 lines (except three lines on East Pier), the anchor locations form a radius of 600’. The fairlead locations for these upper 16 lines vary based on the draft. Due to the proximity of the proposed caissons to the existing piers and the varying bottom topography, considerable turbulence and vortex shedding is expected which will cause current induced dynamic forces on the caissons. This paper describes the design and analysis of this multi-line mooring system for Tacoma Narrows Bridge caissons, based on the construction sequence in the floating condition. The analysis involved optimizing the anchor locations and the line pretensions, determining the dynamic motions of the caissons, maximum line loads, and corresponding safety factors. The paper includes the hydrodynamic analysis for added mass, and damping, the methodology used for the nonlinear moored caisson analysis (MOTSIM), and the validation of the design tool with other similar models (e.g., StruCAD*3D). The results of the analysis and design are discussed.
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Luke, Adam M., Alan F. Rauch, Roy E. Olson e Elliott C. Mecham. "Behavior of Suction Caissons Measured in Laboratory Pullout Tests". In ASME 2003 22nd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2003. http://dx.doi.org/10.1115/omae2003-37023.
Testo completoAbstract (sommario):
Laboratory experiments are being conducted to study the behavior of suction casissons used for deep offshore moorings. Tests with a 100-mm diameter by 910-mm long caisson prototype, which is installed using dead weight or suction, are performed in a 1.1-m thick deposit of normally consolidated kaolinite. Instrumentation is used to record displacements, axial forces, and pore water pressures (at five locations along the interior and exterior surfaces of the caisson) during extraction of the caisson. Axial pullout tests have been conducted on caissons inserted using dead weight only or dead weight plus suction pressure, on caissons pulled with a vented or sealed top cap, and with rapid (undrained) versus slow (drained) pullout. Measured pullout capacities are interpreted in terms of the weight of extracted soil, side resistance on the caisson walls, and the reverse end bearing capacity at the tip.
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Abanades, Javier, Javier Ivars, Rafael Molina e Carlos García. "The Application of Caisson-Type Solutions to the Current Offshore Wind Energy Market". In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77508.
Testo completoAbstract (sommario):
The current offshore wind energy market is not only focused on the design of WTG foundations, but also on the design of offshore infrastructures that lead to an improvement in the current grid connection system, such as artificial islands. For all these type of projects, caisson-type solutions can be applied with numerous advantages. The present article present three different projects in which caisson-type solutions were used: the foundation of a WTG (Gravi3® patent) in the Portuguese Coast, the foundation of a meteorological mast installed in Scotland and the design of an artificial island in the North Sea. The main advantage of this solution is the well-developed construction principle to build the caissons, which is based in the employ of a floating dock in a shelter area. As the caissons are cellular elements, the interior is empty; they float, so they are transported to the place in question to be deployed by means of filling with water the cells that comprised the caisson. This technology is rather used in Spain, being most of the kilometres of breakwater built using caissons thank to their high production rates. The three examples that will be presented in the article are proof of the versatility of this solution. Whereas the case of Gravi3® consists in a gravity based solution for WTG, which is comprised of 3 circular caissons connected by means of a steel tripod; the meteorological mast is formed by a rectangular caisson and a steel shaft. Finally, the artificial island is a mixed solution that uses caissons in the perimeter and hydraulic filling in the inner part. Furthermore, these solutions could be also applied in ports, integrating the WTG on the current or future dikes.
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Krishna, M. Sri, Shen Qiang e P. G. Prasant. "Design and Application of Real Time Monitoring System for Moored Caisson". In ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51231.
Testo completoAbstract (sommario):
Tacoma Narrows Constructors (TNC) is building a new suspension bridge in Tacoma, close to Seattle, Washington State, USA. The new bridge will be built just south of the existing bridge mounted on two caissons, referred to as East Caisson (Tacoma side) and West Caisson (Gig Harbor side). Each caisson is about 80’ wide and 130’ long in plan. The caissons are moored in place in high currents in the Narrows by two sets of mooring lines on each of them — lower set and upper set. The target positions of the new caissons are very close to the existing pier. Therefore the motions of the caisson are very critical for the success of the project and the final touchdown position of the caisson is also of main concern. The mooring monitoring and advisory system ZenMAS has the capability of monitoring the performance of the caisson in currents by acquiring real time data from instruments. Real time line tensions and GPS data are read. The instantaneous tension in each of the mooring lines is measured, recorded and reported. Using the real time GPS data, the program reports the translations and rotations of the caissons. There are warnings when any of these are exceeded beyond allowable limits. ZenMAS also has the capability to function as a simulation tool. Future what-if scenarios can be studied using this software and any necessary corrective measures taken. The analysis capabilities of ZenMAS include static and dynamic analysis using the Motion Simulator program MOTSIM [2]. Graphical representation of instantaneous caisson position and summary and detailed output and results are available from the program. A discussion on how this system was designed, typical inputs, outputs, and comparison to actual measured values is made in this paper.
Rapporti di organizzazioni sul tema "Caissons"
1
Dagan, G. Stochastic analysis of transport of conservative solutes in caisson experiments. Office of Scientific and Technical Information (OSTI), febbraio 1995. http://dx.doi.org/10.2172/10117641.
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Hansen, W. R. ,. Westinghouse Hanford. Caisson UNI-1 study provide permanent structure around the cassion fill pipe. Office of Scientific and Technical Information (OSTI), luglio 1996. http://dx.doi.org/10.2172/296581.
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Siegel, M. D., W. C. Cheng, D. B. Ward e C. R. Bryan. Characterization of materials for a reactive transport model validation experiment: Interim report on the caisson experiment. Yucca Mountain Site Characterization Project. Office of Scientific and Technical Information (OSTI), agosto 1995. http://dx.doi.org/10.2172/100445.
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Health hazard evaluation report: HETA-91-090-2175, Caisson Platoon, Ft. Myer, Virginia. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, gennaio 1992. http://dx.doi.org/10.26616/nioshheta910902175.
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