Dissertations / Theses on the topic 'Béton sol'
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Vila, Béatrice. "Comportement des dallages en béton de grande dimension : expérimentation en semi-grandeur, caractérisation de l'interface dalle-sol et modélisation globale." Lyon, INSA, 2006. http://www.theses.fr/2006ISAL0024.
This work was dedicated to the study of concrete floors on ground. The attention was focused on the stresses induced in the structure, while dimensional variations affect the concrete in ambient hydrothermal conditions. A literature review was performed, in which we describe in particular the different shrinkage strains of concrete. Then we dedicated ourselves to the characterisation of slab-soil interface. A semi-scale test campaign was conducted. It allowed us first to define the optimal configurations to limit the interfacial friction, then to establish a two-dimensional behaviour law. This law was introduced into a global model and compared with the results of a semi-scale test on 20 m long beams. We made a couple of simulations to assess the possibility of designing slab lengths larger than those fixed in design guides
Fach, Mohanad Al. "Modélisation tridimensionnelle du comportement sismique du système sol-pieux-pont : prise en compte des non-linéarités du sol et du béton." Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10063/document.
This work includes an analysis of various interactions of soil-piles-structure under seismic loads.mainly concerns with the analysis of the interactions between different elements (soil, pile, foundation, structure). A special attention was devoted to the non-linearity of soil, the development of plastic hinges in the piles and the influence of the soil-pile interface on the seismic response of the soil-pile-structure. The study was conducted using a three-dimensional modeling using the program FLAC 3D. The thesis is presented in three chapters : The tirst chapter presents a literature review of research work related to seismic behaviour of pile foundations.The second chapter includes a three-dimensional analysis of seismic behavior of soil-pile-superstructure taking into account the effect of soil plasticity. The study was conducted on various aspects of the interaction soil-pile-structure. the influence of mechanical parameters of soil and pile. the geometric configuration of the piles groups and the influence of seismic loading and its frequency content.The third chapter deals with specific aspects of the problem. including the development of plastic hinges at the top of the pile. the modeling and the influence of pile-soil interface and behavior of reinforced structures
Fach, Mohanad Al. "Modélisation tridimensionnelle du comportement sismique du système sol-pieux-pont : prise en compte des non-linéarités du sol et du béton." Electronic Thesis or Diss., Lille 1, 2009. http://www.theses.fr/2009LIL10063.
This work includes an analysis of various interactions of soil-piles-structure under seismic loads.mainly concerns with the analysis of the interactions between different elements (soil, pile, foundation, structure). A special attention was devoted to the non-linearity of soil, the development of plastic hinges in the piles and the influence of the soil-pile interface on the seismic response of the soil-pile-structure. The study was conducted using a three-dimensional modeling using the program FLAC 3D. The thesis is presented in three chapters : The tirst chapter presents a literature review of research work related to seismic behaviour of pile foundations.The second chapter includes a three-dimensional analysis of seismic behavior of soil-pile-superstructure taking into account the effect of soil plasticity. The study was conducted on various aspects of the interaction soil-pile-structure. the influence of mechanical parameters of soil and pile. the geometric configuration of the piles groups and the influence of seismic loading and its frequency content.The third chapter deals with specific aspects of the problem. including the development of plastic hinges at the top of the pile. the modeling and the influence of pile-soil interface and behavior of reinforced structures
Kamdem, Mbopda Alain. "COMPORTEMENT MÉCANIQUE ET PHYSICO-CHIMIQUE DES BÉTONS DE SOL SOUMIS A HAUTE TEMPÉRATURE." Electronic Thesis or Diss., CY Cergy Paris Université, 2023. http://www.theses.fr/2023CYUN1225.
Soil concrete is a material produced by mixing soil with a hydraulic binder. It is a possible solution in today's construction industry for works with low compressive strengths, such as the reinforcement of road foundation soils, waterproofing screens, outdoor landscaping for car parks (paving) and earth retaining screens. This material is produced in situ using the soil in place during construction projects, and as opposed to ordinary concrete, its use makes it possible to reduce the carbon footprint associated with transporting aggregates to construction sites. Due to its very high porosity of between 25 and 65% (Denies et al., 2012), soil concrete structures are subject to significant damage affecting their stability when exposed to high temperatures, H/S cycles and carbonation. Given the wide range of cementitious products available on the market, and the variability in the nature of the soil and its grain size, it is important to have a better understanding of the physical and mechanical properties of soil concrete, through laboratory studies to assess its performance. It is with this aim of improving understanding that this research aims to study the mechanical and physico-chemical behaviour of soil concrete subjected to high temperatures and its durability. To do this, we used two natural soils (laterite and clayey sand) and three types of binder: CEM I 52.5, CEM II 42.5 and CEM III 32.5. The experimental work carried out aims firstly to characterize the various constituents of soil concrete (soil and cement). Then, to formulate the soil concrete for different cement contents (150, 200, 250, 300 kg/m3) and for a constant workability of between 32 and 33 cm corresponding to a self-compacting soil concrete. The soil concrete was then characterized physically (density, entrapped air, etc.) and mechanically (uniaxial compression, static modulus of elasticity, etc.). These characterizations were completed by a mineralogical (XRD) and microstructural (SEM) study. Durability tests (H/S cycles and carbonation) and high-temperature tests were carried out on soil concrete specimens aged for 90 days in water, followed by physico-chemical and mechanical characterization. The results obtained for compressive strength show higher values for formulations with CEM III 32.5, followed by CEM I 52.5 and finally CEM II 42.5. Porosity values range from 43 to 62% and are lower for formulations with CEM III 32.5, followed by CEM I 52.5 and finally CEM II 42.5. At high temperatures, formulations made with CEM I 52.5 hold up better than formulations with CEM II 42.5 and CEM III 32.5. The aim is to offer stable formulations for different applications
Ngo, Duc chinh. "Développement d’un nouveau éco-béton à base de sol et fibres végétales : étude du comportement mécanique et de durabilité." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0885/document.
The ecological design of structures and the sustainable development is nowadays of high importance in the construction industry. Thus, alternative building materials such as soil concrete containing a proportion of various ecological components are of high importance nowadays. The aim of producing ecological concrete is to reduce the consumption of cement and thus the CO2 production, to provide alternatives to the impoverishment of resources and to reduce the energy consumption in the production process.In recent years, many changes have been observed in the construction methods with the aim to replace traditional concrete by alternative construction materials such as concrete containing a high proportion of various ecological component called "green" while maintaining acceptable properties for the desired application. For instance, constructions made of cost effective raw soils are of real interest since the thermal and acoustic properties are more important than that of ordinary concrete. However, more researchs are needed in order to have a better understanding of their mechanical properties and their durability.This study aims to optimize the composition of a new ecological concrete constituted of upgraded excavated soil. Several soil concrete mixtures, composed of different proportions of clayey soil, sandy soil and small quantities of cement, lime and hemp fibers have been tested. The mineralogy and chemical composition of clayey soil was studied by X-ray diffraction (XRD) analysis, and by Environmental Scanning Electron Microscopy (ESEM) coupled with the X-Ray Energy Dispersive Spectrometry (EDS). The casting of the concrete mixtures has been realized by vibration, as ordinary concrete, to obtain the required workability on construction sites.Compressive tests have been carried out on samples at different curing time and conditions. The ultrasonic non-destructive technique has been used for monitoring the hardening of soil concrete in function of the curing conditions. As soil concrete presents important volumetric change that can cause the infiltration of water and impact their durability, an experimental investigation on autogenous and drying shrinkage is reported. Water porosity and water absorption tests have been also carried out to evaluate the transfer property of the porous material. The carbonation of this concrete was also evaluated. The durability of the soil concrete was examined by following the deferred deformations and more particularly the endogenous shrinkage and desiccation as well as the flexural creep
Xiao, Xiaoting. "Détermination de gradients de teneur en eau dans les bétons par méthodes électromagnétiques." Nantes, 2015. https://archive.bu.univ-nantes.fr/pollux/show/show?id=fe3c690d-0711-4ffc-964a-9649849c11f2.
Considering the aging problems of civil engineering structures induces the evaluation of durability indicators (such as porosity) and durability monitoring parameters (such as water content and chloride content). From the electromagnetic (EM) non-destructive testing, Ground penetrating radar (GPR) is used by surveying permittivity inside concrete. The general study is composed of three objectives. Firstly, establish a physical and mathematical interaction between the waves and the materials. To better understand the propagation of EM waves inside the material, we have studied on several dispersion models characterizing the dielectric properties of concrete, and used Debye’s model and Jonscher’s model getting good working performance. Secondly, develop a new method for GPR to detect the gradients of relative permittivity in a dispersive material. With knowledge of the speed of radar waves travelling through the medium, we are able to know the relative permittivity of the material. As the material can form a waveguide for EM waves. The phase velocity of the guided EM waves is used to extract the dielectric and geometric information of it. Then, a new inversion method is implemented to estimate the dielectric permittivity and geometry of the waveguides. The one-layer waveguide is developed into multi-layer waveguide by a dielectric mixing model: parallel model. Thus, the new multi-layer waveguide model is validated both on synthetic and experimental data. Finally, monitor water transferring inside the concrete slabs with the new developed method, the results being compared with those from gammadensimetry, considered as reference
Laurens, Stéphane. "Aptitude de la technique radar à la caractérisation du béton d'enrobage - Aide au diagnostic de la corrosion des armatures." Toulouse, INSA, 2001. http://www.theses.fr/2001ISAT0026.
The development of non-destructive testing in civil engineering is related to the aging of structures. This aging is usually accompanied by some changes in the properties of construction materials, which call the needs concerning the mechanical behaviour, the service ability or the aesthetic characteristics of the structure into question. The aim of this study is to adapt radar technology to the physical characterisation of concrete, in order to highlight the conditions leading to reinforcement corrosion (main cause of damages). Indeed, experimental results on concrete laboratory samples show some interesting aptitudes to the assessment of concrete humidity, and chloride contamination. A specific application to the corrosion of reinforcement of concrete bridge decks with asphalt cover is also developed and verified on site through a comparison with half-cell potential measurements. The approach is just consisting in mapping the reflectivity of asphalt-concrete interface in order to locate humidity contrasts and, thus, areas presenting a high corrosion probability. At least, speed, easiness, reliable and non-destructive measurements are qualities, which give to the radar technique a great interest for large scale auscultation
Camba, Castenada José Luis. "Comportement face aux séismes de cinq bâtiments en béton précontraint situés dans la ville de Mexico." Marne-la-vallée, ENPC, 1991. http://www.theses.fr/1991ENPC9114.
This study deals with the structural behaviour and the analysis of the seismic response of prestressed concrete buildings to the earthquake ocurred in Mexico City in september 1985. First, the overall effects of the earthquake on buildings are summarized with specific consideration on the performance of prestressed concrete buildings. Secondly, for five typical buildings, linear analysis of the dynamic response were performed for tridimensionals models, with due consideration of the soil-structure interaction. Additionally, for some buildings, non-linear analyses were performed on planar models representing the behavior of the complete structure. The computed response has been compared with the observed behavior and the main dynamic properties of the models were checked against those derived from ambient vibration tests performed on the buildings. A good approximation was found between computed and measured natural periods of vibration of the structures, when the displacements and rotations at the base of the building due to the deformation of the soil were taken into account. In general terms, the computed response of the building under the effet of a ground motion representative of the one that should have affected it in the 1985 earthquake, corresponded reasonably well the observed performance of the buildings. Nevertheless, in some cases the analysis indicated that the buildings should have eperienced a greater non-linear behavior than what can be percieved from their level of damage. Some reasons for these differences are advanced. Some recommandations about earthquakes resistant design of prestressed concrete buildings are given. The importance of providing lateral stiffness by shear walls of bracing, and of achieving ductility and continuity through ordinary reinforcement, is stressed
Vu, Xuan Hoa. "Comportement des collecteurs renforces : - prise en compte des interfaces et de "l'histoire de l'ouvrage"." Lyon, INSA, 1997. http://www.theses.fr/1997ISAL0060.
Inserted into a French national project, this work consists to analyze the mechanical behavior of old masonry sewers reinforced by gunite. This present report synthesizes the results of the analysis, undertaken by means of the numerical modelling. In broaching main problems linked to this reinforcement type, we emphasize the « Support-Reinforcement » interface effect. For this last, an experimental characterization is undertaken and a existing numerical model is improved to take into account the adhesion. With the improved interface model and the technique of the matter addition on a deformed structure, also developed within the scope of this work, the taking into account of the interfaces and the « structure history » is possible. The modelling performed allows to evaluate the influence, on the global behavior of reinforced sewers, of different factors such that the reinforcement characteristics, the shrinkage effect, the interaction « Sail-Structure », the interface mechanical properties and the existent structure state. Results of the modelling show the role of the « Support-Reinforcement » liaison, the « Sail-Structure » interaction and the shrinkage harmful effect. These results allow to draw practical conclusions and to propose technical solutions in the objective to reduce the shrinkage effect and to improve the reinforcement efficiency
Stavropoulou, Eleni. "Comportement différé des interfaces argilite/béton : caractérisation et modélisation." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI077/document.
The management of radioactive waste is an important environmental issue, in particular in the countries where nuclear power is generated. In Eastern France, The French National Radioactive Waste Management Agency (ANDRA) is investigating the behaviour of a deep geological repository in Callovo Oxfordian clay-rock (COx). The sealing of the underground repository tunnel, is partly ensured by a mechanical barrier made of concrete, directly in contact with the rock. Such projects require prediction of irreversible deformations over a large time scale, in order to assess the durability of the confinement. Even though the physical properties of most of the materials involved (rock and concrete for example) are now reasonably known, there have been only a few studies of the behaviour of the contact interfaces between these materials. This subject is of great importance for predicting a tentative life-time of nuclear waste storage facilities.During this PhD work the mechanical behaviour of the clay-rock/concrete interface has been investigated. The Callovo Oxfordian is considered as an ideal geological barrier because of its extremely low permeability. However, it is governed by a thermo-hydro-mechanical behaviour of high complexity, which is continuously under investigation with both laboratory and in-field experiments. The preparation of the interface samples involved a short study on the liquid water uptake in the unconfined clay-rock. In order to characterise the short-term behaviour of the interface, direct shear tests have been performed under different boundary conditions, using the BCR3D experimental device located in 3SR.The investigation of the long-term mechanical behaviour of the interface required the design of a new experimental apparatus. One of the most important parts of this study includes the conception and development of SInC Box -- Shearing Interfaces Creep Box -- an original device for the study of delayed deformations of interfaces. Different sets of creep tests have been performed on the interface samples allowing the investigation of the interface's delayed behaviour in shear. The post-creep mechanical behaviour of the clay-rock/concrete interface has also been exploited exhibiting great interest. The experimental results of the delayed response have been further analysed using analytical visco-elastic models and numerical simulations
Musielak, Marion. "Etude numérique et expérimentale des transferts de Composés Organiques Volatils du sol à l'air ambiant, en passant au travers du béton." Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2012. http://tel.archives-ouvertes.fr/tel-00753550.
Musielak, Marion. "Etude numérique et expérimentale des transferts de composés organiques volatils du sol à l’air ambiant, en passant au travers du béton." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0088/document.
This thesis is part of the project FLUXOBAT (ANR-PRECODD 2008), which has the overall objective to develop, a robust and reliable methodology for estimating the transfer of Volatile Organic Compounds (VOC) from the soil to the indoor and outdoor air. This work concerns the study, at laboratory scale, of a typical VOC, the Trichlorethylene (TCE), transfer through a model soil (sand) and through the concrete material, under isothermal and dry conditions. Methods used include numerical modeling and a series of laboratory experiments. A preliminary study replicating experiences existing in the literature, with sand only, was first implemented to develop the tools necessary for experimental and numerical modeling of the problem, before the completion of the study with the concrete material, although more complex. The study of transfers in concrete has been divided into several stages. Initially, the transfers in the cement paste, more homogeneous, have been characterized. In particular, the value of the sorption coefficient of TCE in this material was obtained using the experimental response to a "pulse" of pollutant. Then the characteristic parameters (porosity, permeability, crack opening, effective diffusion coefficient) of "complete concrete" test samples were measured. A protocol for complete characterization of concrete slabs has been developed, associated with the creation of a device for the implementation of TCE transfer experiences (compound whose study is complicated by its very aggressive character) and applicable to any consolidated porous medium. The problem of heterogeneity of concrete, due to the presence of aggregates and cracks, has been treated to propose averaged transfer equations, giving a better description of the transfers. The conditions of a "real" pollution incident were reproduced in laboratory, modeled by a sand column topped by a concrete slab and a vacuum cavity representative of a building, in order to study the transfer of TCE and validate the characterization developed in the study. The transfer experiments are reproducible, were numerically interpreted (with COMSOL Multiphysics®), and have confirmed the relevance of the transfer simulation using the characterization developed in this study. This work has enabled, in particular, to highlight the importance of detailed characterization of the concrete, which properties and heterogeneity are exceedingly influential on transfers, and which cannot be described correctly with simplified analytical models. The results include the estimation of parameters characterizing the transfer of VOCs into the concrete, and a keen understanding of transfer of TCE in this material
Dauzères, Alexandre. "Etude expérimentale et modélisation des mécanismes physico-chimiques des interactions béton-argile dans le contexte du stockage géologique des déchets radioactifs." Poitiers, 2010. http://theses.edel.univ-poitiers.fr/theses/2010/Dauzeres-Alexandre/2010-Dauzeres-Alexandre-These.pdf.
These research works are carried out as part of the radioactive wastes geological disposal feasibility study. The current option developed by Andra, includes several cementitious materials in contact with the surrounding Callovo-Oxfordian (COX) (an argillite). Concretes and argillite present very different pore solutions (ionic concentrations and pH). Controlled by the concentrations differences, the aqueous species diffusion in the solids generates chemical and physical disturbances. This study is based on experimental, analytical and numerical works, in order to identify the mechanisms controlling the clayey environment influence on cementitious materials. Two hardened cement pastes (HCP) are studied: a CEM I HCP and a “low-pH” HCP (CEM I cement + silica fume + fly ashe). The latter is especially developed for the geological disposal application in order to reduce the alkaline plume towards the host-rock. Two experimental devices are created: first, the HCP is immerged in a COX pore solution. The conditions are in agreement with the clayey environment chemistry (high pCO2, carbonates and sulfates concentrations, neutral pH…). The tests are carried out at 25°C, over several months (up to 10). The second device allows the clayey rock containment in contact with a HCP at 20°C and 50°C, over several months (up to 12). The materials are saturated: only diffusion controls the soluble species exchanges. All the results obtained show that the CEM I HCP presents decalcification, carbonation and ettringite precipitation; where as the “low-pH” HCP undergoes decalcification, ettringite dissolution and silicate magnesium hydrates formation (M-S-H). When a CEM I HCP is immerged in the COX solution: a calcite crust formation is observed on the external surface, which slows down (clogging) the alteration front progression (100 µm after 10 months). When the same material is put in contact with the COX argillite, a much stronger degradation is observed (1 mm depth after 1 year), inducing porosity opening in the degraded zone layer (no clogging, low carbonation). In this last configuration, at 20°C as well as at 50°C, the alteration front evolution is proportional to the interaction duration. The argillite presents illitisation (due to KOH diffusion from the cement HCP). This mechanism releases silicon and induces C-S-H precipitation with a low CaO/SiO2 ratio (0. 8) at the interface. When the “low-pH” HCP is immerged in the COX solution, a total deconstruction linked to the C-S-H decalcification is observed (low CaO/SiO2 ratio ≈ 0. 8), leading to the formation of amorphous silica. Carbonation has occurred as well as decalcification (calcite precipitation), but its effect is not pronounced enough to lead to clogging (as observed for CEM I HCP). An important capillary pore network is formed. The alteration front evolves as a function of the square root of time (1. 5 mm after 5 months). When the same material is put in contact with the COX argillite (or bentonite), a lower alteration is observed, with the M-S-H formation at the interface. The liberated calcium during the decalcification (C-S-H + ettringite) diffuses towards the clayey material and is substituted to the sodium in the montmorillonite interlayer: no illitisation was identified. The altered zone thicknesses, from both sides from the interface, do not exceed a few hundred microns after 1 year. The reactive transport code (HYTEC) is used to describe the experiments detailed above. It allows reproducing all the mechanisms observed experimentally and then estimating the exchange of all soluble species. These simulations have mainly allowed to validate the experimental assumptions concerning the silicon diffusion from the argillite to the CEM I HCP linked to the illitisation, source of C-S-H precipitation at the interface
Helson, Olivier. "Comportement thermo-hydro-mécanique et durabilité des bétons de sol : influence des paramètres de formulation et conditions d'exposition." Thesis, Cergy-Pontoise, 2017. http://www.theses.fr/2017CERG0860/document.
Soil improvement initially has been used as an economical solution to make soil constructible, particularly in the context of deep foundation methods using piles. There has been growing interest to improve understanding of the behavior of soil-mixing and jet-grouting material, which consist of mixing the soil in place with a hydraulic binder in order to form columns or panels of "soilcrete". In recent decades, these special foundations have had a great success in the United States, Japan and the Scandinavian countries. In Europe, the environmental consciousness and the ongoing trend to reuse existing material to reduce cost of construction are driving companies to contribute to the technological development of this discipline. Some mixing processes now seem to be sophisticated enough to provide structural elements such as foundations and supports.Unlike prefabricated materials, it is difficult to predict the properties of the material obtained through deep soil mixing due to uncertainties related to soil heterogeneity, environmental conditions and the quality of mixing on site. The objective of the thesis work is to address this need for prediction and performantial reliability of soilcrete by studying the influence of the formulation parameters on the physical and mechanical properties of the material. The high quantities of mixing water necessary to obtain a BAP consistency and the small particle size of the soil limit the mechanical properties of the soilscretes and as a consequence, are particularly sensitive to desiccation shrinkage. Besides, the high porosity of these materials also makes them more vulnerable to chemical aggressions. The ultimate objective of the research is to determine parameters for a better visibility of the lifetime of concrete structures in the soil.The approach tested in the laboratory consists of studying different soilcretes composed of "artificial" soils, CEM III / C cement and with a constant W/C ratio. The parametric study reveals a proportion by volume of clay in the soil beyond which the resistance decreases and thus the stiffness of the material can be problematic for some structural uses. The increase in resistance and the associated stiffness of the soilcrete by increasing the cement dosage is also quantified. The results show that the damage by mechanical load depends mostly on the cement dosage. From the experimental results, mathematical relations are proposed for the dimensioning phase. Various tests of accelerated aging help define thresholds for the indicators of durability (porosity and water permeability). The analysis of the microstructure of the material also shows the importance of the paste-aggregate interface and made it possible to identify some mechanisms of degradation in relation to the exposure conditions. To conclude, this work is finalised by a study of the behavior at high temperature
Fares, Reine. "Techniques de modélisation pour la conception des bâtiments parasismiques en tenant compte de l’interaction sol-structure." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4103/document.
Building design according to European seismic code does not consider the effects of soil-structure interaction (SSI). The objective of this research is to propose a modeling technique for SSI and Structure-Soil-Structure Interaction (SSSI) analysis. The one-directional three-component (1D-3C) wave propagation approach is adopted to solve the dynamic soil response. The one-directional three-component wave propagation model is extended for SSI and SSSI analysis. A three-dimensional (3-D) soil is modeled until a fixed depth, where the soil response is influenced by SSI and SSSI, and a 1-D soil model is adopted for deeper soil layers until the soil-bedrock interface. The T-soil profile is assembled with one or more 3-D frame structures, in a finite element scheme, to consider, respectively, SSI and SSSI in building design. The proposed 1DT-3C modeling technique is used to investigate SSI effects and to analyze the influence of a nearby building (SSSI analysis), in the seismic response of frame structures. A parametric analysis of the seismic response of reinforced concrete (RC) buildings is developed and discussed to identify the key parameters of SSI phenomenon, influencing the structural response, to be introduced in earthquake resistant building design. The variation of peak acceleration at the building top with the building to soil frequency ratio is plotted for several buildings, loaded by a narrow-band motion exciting their fundamental frequency. In the case of linear behaving soil and structure, a similar trend is obtained for different buildings. This suggests the introduction of a corrective coefficient of the design response spectrum to take into account SSI. The parametric analysis is repeated introducing the effect of nonlinear behaving soil and RC. The seismic response of a RC building is estimated taking into account the effect of a nearby building, for linear behaving soil and structures, in both cases of narrow-band seismic loading exciting the fundamental frequency of the target and nearby building. This approach allows an easy analysis of structure-soil-structure interaction for engineering practice to inspire the design of seismic risk mitigation tools and urban organization
Seghir, Abdelghani. "Contribution à la modélisation numérique de la réponse sismique des ouvrages avec interaction sol-structure et interaction fluide-structure : application à l'étude des barrages poids en béton." Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00627044.
Massat, Myriam. "Caractérisation de la microfissuration, de la perméabilité et de la diffusion d'un béton : application au stockage des déchets radioactifs." Toulouse, INSA, 1991. http://www.theses.fr/1991ISAT0033.
Ali, M'zé Wahabi. "Évaluation non destructive de la contamination du béton par les chlorures avec la technique radar." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30278/document.
Ground Penetrating Radar (GPR) is an usual nondestructive testing method for the assessment of concrete structures. The benefit of this method lies within its ability to assess quickly a large scale of concrete surface. Generally, GPR is used for the localization of reinforcements or for the thickness measurements. However, GPR can be also used for the diagnosis of concrete because concrete is a porous dielectric material which can modify the propagation of the electromagnetic (EM) waves. Most common results present the ability of GPR to assess moisture. But, GPR could be also used to detect the presence of chlorides into the interstitial concrete solution as chlorides can modify the concrete conductivity and altered the electromagnetic signal waves. However, only few studies have been carry-out on that field. Therefore, in this study, we propose to use GPR electromagnetic waves to evaluate both the water content and the chloride content inside the interstitial concrete solution of several tests concrete samples. So, several groups of concrete samples with the same formulation will be conditioned for different chloride contamination modes. Thereafter, a velocity measurement process will be proposed from the reflected signal wave analysis. In that process, we will show that the velocity is only affected by the water content while the attenuation strongly affected by both the water content and the chloride content. Furthermore, we will test several permittivity models to predict the dielectric permittivity and the loss factor estimated from the concrete samples measurements with the GPR device and the electrical resistivity device
Suescun, Juliana Ruiz. "Courbes de fragilité pour les ponts au Québec tenant compte du sol de fondation." Mémoire, Université de Sherbrooke, 2010. http://savoirs.usherbrooke.ca/handle/11143/1576.
Sbartaï, Zoubir Mehdi. "Caractérisation physique des bétons par radar : approche neuromimétique de l'inversion." Toulouse 3, 2005. http://www.theses.fr/2005TOU30196.
The main objective of the non-destructive evaluation is to obtain information permitting the diagnosis of concrete structures or to quantify input data of durability prediction and/or recalculation models. Among the interesting information to be evaluated on site, water and chlorides content of concrete are a relevant pathological features. The on site quantification of these physical factors and the evaluation of theirs spatial variation are very important. The goal of this research work is related to the application of radar technology for the physical characterization of concrete, especially on the quantitative evaluation of water and chlorides content. The problem has been resolved using statistical approach based on artificial neural network model. Experimental data base was then implemented, which related physical characteristics of concrete and radar parameters. This data base has been leaded to develop neural network model of radar measurement able to predict, with satisfactory error, water and chlorides content of concrete made in laboratory
Yin, Kexin. "Influence of clay fraction on the mechanical behavior of a soil-concrete interface." Thesis, Ecole centrale de Nantes, 2021. http://www.theses.fr/2021ECDN0015.
In geotechnical engineering, the soil-structure interface is an important aspect to take into account in soil structure interactions because it relates to the stability of the supported structure. In particular, the mechanical behaviour of the interface plays a key role in the design of civil engineering structures and their analysis over time. The interface is a thin zone of soil in contact with the structure where major stresses and strains develop in. To our knowledge, previous works on the characterization of the mechanical behaviour of the soil-structure interface mainly include typical soils (sand or clay) or natural soils, in contact with variable structural materials (concrete, steel, wood). However, natural soils are very complex, partly due to geological heterogeneities, and the mechanical response of typical soils do not always represent accurately intermediate soils between sand and clay. Previous studies on the mechanical behavior of those soils are significantly represented in the literature, especially in experimental research, however it is rather poorly documented on the interface between these soils and structural materials, whereas their response to mechanical loadings is different. Moreover, at the engineering scale, there is still a lack of understanding on how this interface behave along loaded pile within soils between sand and clay, numerically, and experimentally due to instrumentation restrictions along the pile. The objective of this thesis is to characterize the mechanical behaviour of the soil-structure interface for intermediate soils between sand and clay, both by experiments at the laboratory scale and by models at the engineering scale. Artificial mixtures of silica sand and kaolinite-rich clay are chosen to represent intermediate soils in this study. For this propose, the research is organized in a first and main experimental campaign that aims to investigate the effect of the clay content, from 0% (sand) to 100% (clay) on the mechanical behavior of a soil-concrete interface by a new interface direct shear device in the laboratory. A particular attention is given to the design of the setup, and to the investigation of four sample preparations to insure an optimize sample homogeneity. A second and numerical campaign is performed to input the results from the experimental campaign, to model the mechanical response of the interface between sand-clay soils and a lateral concrete loaded pile at the engineering scale. A new subroutine of a MATLAB finite element code is implemented to perform the numerical modelling of the interface’s response via the p-y curves. The characterization of the mechanical behaviour of the soil-structure interface at different clay and sand fractions allows to enlighten the role of soil microstructure at the soil-structure interface on the stability of civil engineering structures
Diaz, Caselles Laura. "Stabilisation des sulfates et du molybdène par des liants alternatifs." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30255.
Excavation operations produce several tons of soil generally contaminated by the presence of pollutants. Excavated soil is considered as waste and it can be either sent to landfill or destined for reuse depending on the level of pollution. In any case, soil should be properly treated in order to: (i) decrease the release of pollutants into the environment, and (ii) minimize the problems involved in civil engineering applications due to the reactions between cementitious phases and pollutants. In the context of this thesis, we focused on sulfates and molybdenum (Mo). Concerning sulfates, we considered two main issues: (i) external sulfate attack of concrete structures, which are in direct contact with sulfate-rich soil (e.g. dams, foundations), and (ii) the release of sulfates into solution in addition to the swelling and mechanical strength loss in sulfate-rich soil intended for valorization (e.g. reuse in road construction). In the case of Mo, its release into solution is also a serious concern as it can lead to significant risks for the environment. Therefore, in this thesis, we investigated the reaction of concrete in contact with sulfates, and the stabilization of sulfates by using alternative binders for pollution reduction and for reuse of soil. Additionally, we studied the interaction of Mo with alternative binders and their capacity to stabilize Mo. First, we studied the capacity of seven different concretes to resist external sulfate attack under similar experimental conditions. It was found that ordinary Portland cement had high expansions (>0.1%) due to the formation of ettringite in excess caused by the reaction between aluminates and sulfates. Portland cement without C_3A presented lower expansions but gypsum was found to be responsible of cracking at later ages. Meanwhile, alternative binders had low expansions in the range of 0.01-0.03% explained by the absence of C3A and portlandite, in addition to the formation of ettringite during hydration (case of ettringite binders) and the absence of calcium (case of the geopolymer-based metakaolin). Second, we compared the capacity of four different binders to stabilize sulfates in a sulfate-spiked soil. Binders having high C_3A content led to high volume expansions (>5%) caused by the formation of ettringite in excess. These binders also released heavy metals into solution due to their high clinker content. In contrast, binders containing ground granulated blast furnace slag (GGBS) led to low expansions (<2%), sulfate retention was about 89% and lower heavy metals contents were detected in solution. Sulfate solubility was controlled by ettringite, which did not lead to expansion probably due to the low kinetics of precipitation in addition to the absence of portlandite, which is often related to expansive ettringite.[...]
Yavari, Neda. "Aspects géotechniques des pieux de fondation énergétiques." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1160/document.
Energy pile efficiency has been tested and validated by numerous studies from environmental and energy-related points of view until now. Nevertheless, energy pile technology is still more or less unknown and rarely applied in construction, especially in France compared to other European countries. The chief reason for this lack of attention might be the limited knowledge of the impact of the coupled thermo-mechanical loading on the behaviour of the pile and that of the surrounding soil. This thesis aims to study the geotechnical aspects of energy piles through physical modelling and some numerical investigations. A physical model is developed in order to better identify the soil/pile interaction under thermo-mechanical loading. The model is made up of a small pile equiped with a heat exchanger loop embedded in compacted soil. The pile was once installed in dry sand and then in saturated clay; it was then loaded mechanically and was subjected to thermal cycles. The effect of mechanical load value, number of thermal cycles and soil type is studied. The results show the appearance of irreversible settlements during thermal cycles, whose quantity increases as the pile head load increases. Total pressure in the soil close to the pile surface does not change by cooling and heating, while total pressure below the pile increases gradually as thermal cycles proceed. This is in accordance with the permanent downward movement of the pile within thermal cycles. Experiments also show the evolution of axial force profiles with temperature, axial force in the pile increases by cooling and decreases by heating. In another part of the experimental work, we focused on the soil/pile interface. The shear behaviour of the soil (the same as the soils used above) and that of the soil/concrete interface was evaluated at different temperatures. To do this, a conventional shear apparatus was equipped with a temperature control system. Soil (and soil/concrete interface) was subjected to a rather low range of stress. Thermal consolidation was performed according to a special protocol. It was observed that the soil friction angle and cohesion do not change considerably relative to temperature. The numerical study was initiated by simulating existing tests in the literature on energy piles through a finite element code well-known to engineers, applying a simplified method. The thermal load was simulated by imposing volumetric strains calculated from the coefficient of thermal expansion of the material on the pile. The method successfully simulates the behaviour of some full-scale energy piles in terms of axial strain and pile head displacement. The results highlight the important role played by the pile thermal volume change on the mechanical behaviour of the energy pile under various thermo-mechanical loadings. In the second stage, another numerical code with the possibility of including temperature effects was used for modelling the tests formerly performed on the physical model. Thus, compared to the first numerical attempts, the soil thermal volume change is also taken into account. The numerical results were compared with the experimental ones obtained from physical modelling. It was deduced that the numerical model could simulate correctly the pile behaviour under purely mechanical loading. Also, simulating thermo-mechanical tests, a good estimation of heat conduction in the soil was achieved numerically. Regarding the mechanical behaviour of the pile under thermal cycles, the numerical model adequately predicts the gradual ratcheting of the pile as observed in the experiments. However in terms of axial force distribution in the pile, the results from numerical modelling are different from the physical one
Marzougui, Salsabil. "Transfert d'un composé organo-chloré depuis une zone source localisée en zone non saturée d'un aquifère poreux vers l'interface sol-air : expérimentations et modélisations associées." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-00853290.
Marzougui, Jaafar Salsabil. "Transfert d'un composé organo-chloré depuis une zone source localisée en zone non saturée d'un aquifère poreux vers l'interface sol-air : expérimentations et modélisations associées." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAH003/document.
Two experiments were conducted on the experimental platform "SCERES" to assess the TCE vapour concentrations and fluxes in SCERES with two concrete slabs installed, one after the other, on the ground surface. This artificial aquifer is a large scale (25 x 12 x 3 m3) heterogeneous porous medium. The results showed that the TCE vapour plume covers most of the basin 3 weeks after the creation of the TCE source area in unsaturated zone. The heterogeneity of SCERES has generated a non uniform vertical distribution of the TCE vapour concentration. Simulation of vapour plume in SCERES was carried out by the multiphase code "SIMUSCOPP".The presence in SCERES of a low permeability and low diffusive medium compared to the sand in the basin,as a concrete slab, constituted a "barrier" for the transfer of TCE vapour to the interface concrete slab / atmosphere. To better quantify the TOE fluxes through the concrete slab, a study of diffusion coefficient and permeability of both concrete slabs was done. An upward vertical movement of the water table has generated a strong soil air pressure driving gradient, which led to a strong increase in the TCE vapour concentrations near the surface which has increased the vapour fluxes at the interface soil / atmosphere. Quantification of vapour fluxes at the interfaces soil / atmosphere and concrete slab / atmosphere was performed using a semi analytical approach based onFick's and Darcy's laws by taking into account both the effect of the driving pressure gradient and the effect of density vapour on the vapour transfer towards the soil surface.The intrusion of TCE vapours into the model building installed on the concrete slab was generated by creating a vacuum. The results showed that, during the TCE vapour suction from the model building, the concentration of TCE vapours under the concrete slab and in the building increases. Simulation of vapour intrusion into indoor air was done by the computational Multiphysics code "COMSOL", allowing simulation of the evolution of the vapour concentration obtained experimentally in the building. Il was shown that they depend directly on the spatial-temporal variation of the mass flux through the slab
M'jahad, Sofia. "Impact de la fissuration sur les propriétés de rétention d‘eau et de transport de gaz des géomatériaux : Application au stockage géologique des déchets radioactifs." Thesis, Ecole centrale de Lille, 2012. http://www.theses.fr/2012ECLI0023/document.
In the context of geological disposal of radioactive waste, this work contributes to the characterization of the effect of diffuse damage on the water retention and gas transfer properties of concrete (CEM I and CEM V) selected by Andra, Callovo-Oxfordian argillite (host rock) and argillite / concrete interfaces. This study provides information on the concrete microstructure from Mercury porosimetry intrusion and water retention curves: each concrete has a distinct microstructure, CEM I concrete is characterized by a significant proportion of capillary pores while CEM V concrete has a large proportion of C-S-H pores. Several protocols have been developed in order to damage concrete. The damage reduces water retention capacity of CEM I concrete and increases its gas permeability. Indeed, gas breakthrough pressure decreases significantly for damaged concrete, and this regardless of the type of concrete. For argillite, the sample mass increases gradually at RH = 100%, which creates and increases damage in the material. This reduces its ability to retain water. Otherwise, water retention and gas transport properties of argillite are highly dependent of its initial water saturation, which is linked to its damage. Finally, we observed a clogging phenomenon at the argillite/concrete interfaces, which is first mechanical and then hydraulic (and probably chemical) after water injection. This reduces the gas breakthrough pressure interfaces
Abakar, Ali. "Caractéristiques mécaniques et thermiques de l’argile stabilisée par la gomme arabique et renforcée par la paille de riz." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0066.
Global warming and the high cost of conventional building materials (cement, lime, steel) force us to use local, available materials with no negative effect on the atmosphere. These are compressed earth blocks (BTC) stabilized with arabic gum and reinforced with rice straw. The main objective of this work is the valorization of local and ecological materials for the construction of sustainable homes. The study concerns the mechanical, thermal and durability characterization of specimens made of clay, sand, arabic gum, rice straw and water in different proportions. For this purpose, the percentages of gum Arabic are 5%, 10% and 15%. Those of rice straw are 0.5%, 1%, 1.5% and 30% of sand are retained for this research work. BTC bricks measuring 30 x 15 x 8 cm and specimens measuring 4 x 4 x 16 cm are manufactured to perform the mechanical tests. A "hot wire" method adapted to cylindrical specimens 16 cm in diameter and 32 cm in height is used for the determination of thermal conductivities. The use of arabic gum as a binder in the construction has given satisfactory results. At a rate of 15% gum Arabic associated with a much higher compressive stress, allow us to obtain BTCs having an acceptable mechanical strength as well as a better resistance to rainwater. Mechanical results show that gum Arabic improves mechanical strength. As is the compaction constraint. By cons the use of rice straw in the mixture reduces its mechanical strength and lightens the material. The measured thermal conductivity values show that the different formulations cannot be considered as insulating materials. The specimens exposed to the climatic hazards (rain and moisture) for a month show that the unstabilized earth blocks have deteriorated in the rain. On the other hand, samples stabilized by gum Arabic have retained their good habits. Similarly, stabilized and unstabilized specimens are immersed in water. From 15 min, all test pieces are deteriorated. The clay materials stabilized by gum Arabic can not be used as a foundation in construction. This research work will be completed by aging tests on the various formulations for validation as a new sustainable building material
Martinez, Hernandez Heriberto. "Amélioration de granulats de béton recyclé par bioprécipitation." Thesis, Ecole centrale de Nantes, 2022. http://www.theses.fr/2022ECDN0009.
Recycled concrete aggregates (RCA) contain, due to their origin, residual cement paste which gives them high porosity and moderate performance. The porosity leads to a strong water absorption. This is a major difficulty on the industrial level because it complicates the adjustment of water in concrete batches, which allows to control their workability in production. The RCA manufacturing process results in having more paste in the finer particles and therefore more absorption. As a result, while the industry today recycles coarse RCA into concrete relatively well, it uses small amounts of RCA sand because of their greater porosity. Yet, during the manufacture of RCA, about 50% sand and 50% coarse aggregates are obtained. Consequently, the porosity of RCA sand hinders the circular economy of concrete. A number of techniques have been proposed for removing or improving the residual cement paste, but they are expensive. The natural carbonation of RCA by atmospheric CO2 helps with decreasing their water absorption by obstructing their porosity, but this is a several month reaction. Research is ongoing to make accelerated carbonation (by concentrating CO2, for example) on an industrial scale. The present work explores an alternative idea, which consists in forming in a few days, using biocalcifying bacteria, a matrix of CaCO3 around the RCA and especially the sand part, in order to limit the access of water to their porosity. First, candidate non-pathogenic bacteria were identified, selected, adapted to the alkaline medium of RCA, then we checked their ability to produce CaCO3. In a second step, we detemined the conditions, which favor uniform bacterial colonization and production of CaCO3 on the surface of model agar media. Homogeneity is indeed mandatory to obtain good water tightness. We thus confirmed the value of selecting bacteria capable of producing biofilm. Finally, the methods developed were applied to model mortar disks facilitating visual observations. Preliminary results confirm that it is possible to significantly lower the absorption of these mortars within one month. Further work is needed to confirm these encouraging results on sand part of RCA
Yehya, Mohamad. "Propriétés de transfert dans le béton par imagerie neutronique." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI103/document.
For civil engineering structures, especially containment buildings during a severe accident, the permeability of concrete is a key issue. Current permeability measurements allow only average (structural) magnitudes, which are not suitable for heterogeneous samples (cracks and/or reinforcements). Understanding the details of fluid flow is crucial because of the implications of preferred pathways (steel/concrete interface, cracks, etc.). The aim of this thesis is to propose a new methodology, and to test a new experimental setup, using neutron imaging at the D50 beam line at the Institute Laue Langevin in Grenoble to measure flow directly. The test consists of injecting normal water (H2O) under high pressure, into a concrete sample casted and saturated with heavy water (D2O), in order to follow the evolution of a waterfront over time by difference of attenuation between these two waters. An experimental campaign was launched on concrete specimens in different configurations (proper concrete, cracked concrete and concrete with reinforcement) and measurements of local permeability in singularities (cracked zone, reinforcement-concrete interface, etc.) were done. Tests have shown that classical permeability measurements are underestimated and flows in concrete are controlled by defects
Morin-Morissette, Pierre-Olivier. "Étude de la durabilité à l'écaillage en présence de sel fondant des bétons avec liant ternaire." Mémoire, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/10503.
El, Merabi Bassel. "Comportement mécanique des joints cohésifs de béton-granite au niveau de l'interface barrage-fondation : influence géométrique et mécanique des aspérités." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI008/document.
The shear strength of the concrete-rock interface is a key factor in assessing the stability against sliding of concrete dams founded on rock. While several studies have shown that both surface roughness and the initial cohesion contribute to the shear strength, most of the recommendations for the stability assessment of dams propose conventional values for the mechanical parameters of the dam-foundation interface (i.e. friction angle and cohesion). Moreover, most of the criteria proposed in the literature in order to determine the shear strength of rough joints are based on direct shear tests conducted on joints without initial bonding. Another major difficulty lies in the quantification of surface roughness by means of an objective parameter able to describe the three dimensional aspect of surface roughness as well as the anisotropy observed experimentally. In this context, one of the primary objectives of this thesis is to better understand the shear behavior of bonded rough joints and to relate the shear strength to the morphological parameters of the concrete-rock interface.Due to the complexity of the shear behavior of bonded joints and because few studies have been carried out on cohesive samples, it was decided to perform several experimental campaigns on different types of geometries with an increasingly complex roughness (smooth, bush-hammered, tooth-shaped asperities and natural surfaces). For this purpose, more than thirty direct shear tests were performed on bonded samples at three levels of normal stress. The influence of the shear displacement rate on the shear behavior of joints was also investigated. Prior to the shear tests, a morphological tool was developed in order to provide an objective quantification of surface roughness based on surface measurements obtained with a laser profilometer.Based on the shear test results, two different shear behaviors were observed for the natural joints according to surface roughness and the level of normal stress. Thus, an analytical expression was proposed in order to quantify the contribution from the different modes of failure to the shear strength. It is shown that this expression is able to well predict the shear strength of natural joints. Furthermore, a new roughness parameter was proposed in order to quantify the morphology of natural joints and to account for the different levels of surface roughness involved in the shearing mechanism. This parameter was found to be well correlated with the shear strength of joints sheared at a normal stress less than 0.6MPa.On the other hand, numerical simulations of the direct shear tests were conducted by using a 3D finite element code and by incorporating the reconstructed joint surface obtained from the laser profilometer. Two different models were used: a cohesive-frictional model for the pre-peak phase and a contact law for modeling the residual shear behavior. The mechanical parameters of the concrete-granite interface were obtained from the results of the experimental campaigns on bush-hammered samples. The comparison between the numerical results and the experimental data showed a good agreement in the residual phase. The use of a cohesive-friction model, on the other hand, allowed to mimic the overall shape of the shear stress curve
Segni, Rachid. "Caractérisation structurale, propriétés d'échange et stabilité de matériaux de type hydrocalumite [Ca2M(OH)6]+[Xn 1/n. xH2O]- avec M=Al, Fe, et Sc et X=SO4, CrO4, V2O7 et SiO3." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2005. http://tel.archives-ouvertes.fr/tel-00688377.
Cidreira, Keserle Gilberto. "Exposition environnementale des structures en conditions hivernales sur un réseau routier." Doctoral thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/66591.
Modeling the impact of the various rehabilitation methods, as a function of the initiation time of the damage, is the major challenge in the field of structural durability. The durability of a structure is directly linked to the exposure conditions influenced by the climate and the environment where the structure is located. Depending on the degree of exposure, the rate of degradation of structures can then accelerate or be slow. This work develops an in-depth study on the exposure of structures in winter conditions, which includes the use of de-icing salts. A survey was carried out to find out the amount of salt used in Quebec and Canada. In addition, the three most used types of de-icing salt were evaluated to determine its speed of progression in concrete under severe winter conditions. A mobile weather station MexStUL, designed with several sensors of temporal measures, has been developed to monitor exposure conditions in two different experimental sites on severe winter conditions during 2018/19. It was then possible to predict the climatic (temperature, humidity, speed and wind direction, sunshine and precipitation) and environmental factors (traffic, road condition, salt concentration on road, splashes and salt laden mist) relating to the conditions of exposure of the structures. Models were proposed to predict exposure condition using a meteorological station and evaluation of spatial influence of de-icing salt on different types of exposure as well. A new sensor has been developed, measuring the concentration of salt laden mist under severe winter conditions. Results demonstrate an important spatial variability on stagnant water. A model about spatial influence of brine splashes is proposed to delimit this type of exposure. Airborne concentration during winter climate shows an important evolution and a concentration model is proposed and the volume of salt laden mist is also determined during winter.
Diouf, Babacar. "Evaporation avec cristallisation de sel en milieu granulaire : localisation des cristaux et déplacements mécaniques induits." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30084.
The crystallization of salt, initially dissolved in water, from porous materials (like cements, concrete, mortar, bricks) is a major cause of degradation occurring in buildings and in certain elements of our cultural landscape (monuments, walls, sculptures, frescoes,). Salt crystallization at the surface of a porous medium (efflorescence) don't affect structure durability but create an aesthetic problem for building construction. However, when salt crystallization occurs inside the porous media (subflorescence), pressure on the solid matrix can damage structures by cracking. In this context, the present work focuses on evaporation with salt crystallization in a granular medium and in particular on the locus of crystals and induced mechanical displacements. The first part of this thesis focuses on the study of the factors controlling the localization of crystals atthe surface of an heterogeneous medium. This study is based on the identification of two basic situations of evaporation. In the first so-called evaporation wicking situation, the porous medium is in contact at its bottom with an aqueous solution and the medium remains fully saturated by the solution during evaporation. This situation may correspond to lower parts of walls or structures, when the material is close to the ground water. The second so-called drying situation can correspond to materials located sufficiently high in a wall or a structure. Contrary to the case of wicking situation, the porous medium isn't supplied with a saline solution when evaporation occurs. These two situations lead to a markedly different locus of the efflorescence formation: on the surface of the coarse medium in drying situation and on the surface of the fine medium for the wicking situation. The study emphasizes the key-role of the velocity field induced in the porous domain in the case of the evaporation-wicking situation. In the case of the drying situation, a key aspect lies in the local increase in the ion mass fraction due to the local desaturation, i.e. the local shrinking of the liquid volume containing the ions. Regarding the colonization of the entire surface of the porous medium by efflorescence, the study suggests that there is a critical evaporation rate against which this phenomenon appears. The second part of the thesis deals with the study of surface heave phenomena using experiments in quasi-two-dimensional Hele-Shaw cell supplemented by experiments in a confined granular medium of cylindrical tubes. A growth model of subflorescence is proposed in which the growing subflorescence is controlled by evaporation and not by the precipitation of salt. This model predicts a very slight supersaturation on the top of the subflorescence compatible with the existence of a crystallization pressure. This model makes it possible to identify two main regimes of displacement: a regime known as desaturation of the subflorescence and a clogging regime. Simple expressions are proposed to estimate the growth of subflorescence and thus the induced displacement. These relationships make it possible to determine the supersaturation at the top of the subflorescence and therefore the crystallization pressure
Wang, Xiaomeng. "Modélisation du transport multi-espèces dans les matériaux cimentaires saturés ou non saturés et éventuellement carbonatés." Phd thesis, Université Paris-Est, 2012. http://tel.archives-ouvertes.fr/tel-00730834.
Pruvost, Charlotte. "Potentiel de la Biodiversité dans la construction de Technosols à partir de déchets urbains." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1161/document.
Topsoil requirements for the development of urban green spaces induce a harvest of agricultural or natural soils. On the other hand, huge volumes of deep horizons excavated during the construction of buildings are dumped on the outskirts of cities, with an impact on the environment. The recycling of these inert wastes for the construction of soils for green spaces appears as a promising solution. However, it is necessary to ensure that these constructed Technosols are suitable for plant and animal diversity, and can deliver ecosystem services, as proposed by this thesis. The composition of the material mixes (deep horizons, urban green waste compost, crushed concrete) was manipulated in a 4000 m² experiment in collaboration with the company ECT and CD 93. A four-year monitoring showed that the compost used was responsible for the death of some trees, but associated with concrete, it greatly increased their growth rate and macrofaunal colonization. In the meadow land use, the addition of compost increased biomass production and altered the assemblage of the plant community, favoring competitive species, but no effect on macrofauna assemblage was observed. In a mesocosm experiment aiming at studying the link between plant diversity and productivity, complementarity between species was observed for one of the three communities, at an intermediate level of fertility. It is therefore possible to improve the primary productivity of new ecosystems by manipulating the composition of the mixtures of materials while avoiding the dominance of certain species, in order to preserve diversified communities
Kotronis, Panagiotis. "Stratégies de Modélisation de Structures en Béton Soumises à des Chargements Sévères." Habilitation à diriger des recherches, 2008. http://tel.archives-ouvertes.fr/tel-00350461.