Hospitals are regarded as some of the most important structures in society due to the service that they provide. Knowing this, governments spend large amounts of money on these facilities. Also, codes of design require to provide them more reserve capacity than that for conventional structures. However, large damages (such as collapses and permanent or temporary interruptions of their functionality) have still been observed in hospitals during strong earthquakes. Unfortunately, it is precisely after this type of event that their service is in high demand and failure in providing that service could lead to further disastrous or fatal consequences. Therefore, the use of protective technologies, combined with rational procedures of design, would help to reduce damage and probable losses of functionality in hospital structures. In this thesis, a procedure for seismic design of structures equipped with a type of protective technology, namely, buckling-restrained braces (BRBs), is proposed. Then, the results of experimental and numerical studies are presented to understand the benefits of using BRBs in structures. This study highlights that BRBs are very effective to dissipate seismic energy and can act as structural fuses, i.e. disposable devices that may be replaced after an earthquake without interruptions in the functionality of the structure. One of the advantages of the proposed procedure is that it takes into account explicitly the characteristics and contributions of both, the main structure and the BRBs. It is based on the assumption that a structure protected with BRBs can rationally be represented by a dual SDOF system whose parts yield at different displacement levels. Other advantages include: 1) better control of the displacement demands on the structure; 2) achievement of the fuse concept beforehand; and 3) rapid assessment of the probabilistic performance of the structure. The experimental studies consisted of testing steel and concrete models, with and without BRBs, on a shaking table. In addition to calibrate and validate the proposed method of design, the tests have helped to find that, due to BRBs: 1) the damping ratio is increased significantly; and 2) the dynamic response, to ground motions characteristic of the lakebed zone of Mexico City, is reduced in terms of lateral displacements, inter-storey drifts, floor velocities and floor accelerations. The numerical studies are: 1) a study of the response of typical hospitals improved with BRBs; 2) a study of residual displacements in conventional and dual systems; and 3) evaluation of the economic benefits of using BRBs in structures. On these studies, hypothetical hospitals located in the lakebed zone of Mexico City were considered. The results show that the use of BRBs is very beneficial in medium- and low-rise buildings, while adverse effects may be observed in high-rise structures.

Liquefaction is a phenomenon in which soil loses a large percentage of its shear resistance due to increased pore water pressure and flows like a liquid. Undrained cyclic loading conditions during earthquakes cause liquefaction of soils, which can lead to catastrophic failures such as bearing capacity failures, slope failures and lateral spreads. The concepts and mechanisms of liquefaction were studied extensively by many researchers. Though the factors affecting the liquefaction response of soils during earthquakes are well documented in literature, there are still some gray areas in understanding the individual and combined effects of factors like frequency, gradation, fines content and surcharge pressure on the initiation of liquefaction. The objective of this thesis is to study the influence of ground motion, soil and site parameters on the initiation of liquefaction in saturated sand beds through laboratory shaking table model tests and numerical studies. Shaking table tests are carried out using a uniaxial shaking table on sand beds of 600 mm thickness. The initiation of liquefaction was observed and identified by measuring the pore water pressure developed during the sinusoidal cyclic loading. Free field liquefaction studies are carried out on sand beds to study the influence of ground motion parameters, namely, input acceleration and frequency of shaking on liquefaction. These studies revealed that acceleration is one of the important parameters that can affect the initiation of liquefaction in sands. Increase in acceleration reduces the liquefaction resistance of sand and a small increase in acceleration can trigger liquefaction. Frequency of shaking did not affect the initiation of liquefaction at lower frequencies but a threshold frequency which triggered instant increase in the excess pore pressures is observed. Liquefaction caused slight initial amplification followed by de-amplification of accelerations due to the stiffness reduction in soils during liquefaction, the effect being more pronounced in the top layers of the sand bed. Pore water pressure ratios during dynamic loading decreased with depth below the surface of the sand bed due to the low initial effective vertical stress and upward transmission of pore pressure during undrained loading. Shaking table tests are carried out to study the influence of soil parameters such as relative density, thickness of dry overlying sand layer and gradation. Relative density of sand can influence the liquefaction potential of sand to a great extent, about 10% increase in relative density bringing down the probability of liquefaction by about 50%. With the increase in height of dry overlying sand layer, liquefaction potential has decreased nonlinearly. Change in grain size altered the pattern of liquefaction and pore pressure development and it is observed that the liquefaction in finer sands is influenced by the frequency of shaking to a larger extent. Surcharge pressure from building loads increased the liquefaction potential and heavier structures got liquefied at lower pore water pressure ratios. Significant post-liquefaction de-amplification was observed in sand beds with surcharge pressure. Parametric numerical analyses are carried out using finite difference program FLAC (Fast Lagrangian Analysis of Continua) with FINN model to measure pore water pressures in the sand bed. Results from numerical analyses with change in the acceleration, surcharge pressure and thickness of dry overlying layer agreed well with the experimental results. However, effect of frequency in numerical studies did not match with the experimental observations, because of the inherent boundary effects in the experimental models. Results from this thesis provided important insights into the development of pore water pressures in sand beds during cyclic loading events, apart from enhancing the understanding towards the effect of various ground motion, site and soil parameters on the initiation of liquefaction in sand beds.

La procédure d’évaluation des performances des structures en génie civil soumis à des tremblements de terre implique le développement des modèles mathématiques et des procédures d’analyse dynamique non-linéaire pour estimer les réponses sismiques. Le comportement hystérétique des structures est connu pour être fortement dépendante du modèle de l’assemblage. Dans le cas de chargement cyclique, la plastification cyclique, le phénomène de fatigue oligocyclique et la détérioration du comportement dus à la dégradation de rigidité ont été jugées importantes. Cela éventuellement conduit à une grande incertitude dans les réponses d’une structure. Dans ce contexte, un modèle d’endommagement basé sur la fatigue hystérétique est développé pour évaluer la performance sismique des ossatures en acier avec des assemblages boulonnés à plaque d’extrémité. Le modèle développé est un modèle hystérétique dégradant basé sur l’indicateur de dommage par fatigue oligocyclique. Une étude expérimentale du comportement d’un assemblage boulonné à plaque d’extrémité est réalisée pour analyser les effets du comportement en fatigue oligocyclique et pour développer un modèle de prédiction de durée de vie. Les essais de fatigue ont été effectués en utilisant un pot vibrant. Les résultats des essais expérimentaux de fatigue seront utilisés pour déduire les paramètres de la fatigue qui sont nécessaires pour développer le modèle hystérétique de l’assemblage boulonné. L’analyse des dommages sismiques est l’un des problèmes les plus difficiles dans des structures grandes et complexes, particulièrement celles en ossature avec des assemblages boulonnés à plaque d’extrémité. L’existence de dommages structuraux dans une structure conduit à la modification des modes de vibration et les valeurs propres globaux sont généralement sensibles à l’ampleur des dégâts sismiques locaux dans des assemblages boulonnés. Dans ce travail, une analyse temporelle non-linéaire qui tient compte des modes et des fréquences non-linéaires a été proposée. Selon cette approche, les modes et les fréquences non-linéaires peuvent être déterminés par une procédure itérative qui repose sur la méthode de linéarisation équivalente. L’introduction de la notion des modes non-linéaires a permis d’étendre la méthode de synthèse modale linéaire aux cas non-linéaires afin d’obtenir la réponse dynamique des systèmes non-linéaires. Dans un autre contexte expérimental, cette thèse présente les résultats d’essais sur une table vibrante. L’objectif des essais expérimentaux est de comprendre le comportement inélastique des structures en acier soumis à des charges dynamiques. Par ailleurs, ces essais sont également destinés à étudier les changements dans les paramètres modaux dus au développement du comportement élasto-plastique et du dommage par fatigue oligocyclique des assemblages boulonnés. Une simulation numérique non-linéaire du système est effectuée sur la base du modèle développé et l’approche numérique proposée. Une comparaison des résultats obtenus à partir de l’analyse numérique et ceux des essais de table vibrante est présentée. Cependant, l’analyse des dommages pour les ossatures en acier sous excitations sismiques aléatoires exige l’application d’un algorithme adéquat. Un algorithme a été développé pour évaluer la performance sismique des ossatures en acier. En utilisant cet algorithme, l’influence de la fatigue oligocyclique sur le comportement des assemblages boulonnés à plaques d’extrémité peut être étudiée. / The performance assessment procedure of civil engineering structures subjected to earthquakes involves the development of mathematical models and nonlinear dynamic analysis procedures to estimate seismic responses. The hysteretic behavior of structures was known to be strongly dependent on the connection model. In the case of cyclic loading, cyclic hardening, low cycle fatigue phenomena and deterioration of the behavior due to stiffness degradation were found to be important. This eventually led to high uncertainty in the responses of system. In this context, a Fatigue Damage-Based Hysteretic model is developed to evaluate the seismic performance of steel moment-resisting frames with end-plate connections. The developed model is a degrading hysteretic model based on the low cycle fatigue damage index. An experimental study of the behavior of a end-plate bolted connection is performed for analyzing the effects of low cycle fatigue behavior and developing a model for predicting life of end-plate bolted connection. The fatigue tests were conducted using a shaker. The experimental fatigue results will be used to derive the fatigue parameters that will be used to develop the hysteretic model of the bolted connection. Analysis of seismic damage is one of the most challenging problems in large and complex structures, particularly those in steel moment-resisting frame with end-plate bolted connections. The existence of structural damage in an engineering structure leads to the modification of vibration modes and global eigenvalues are usually sensitive to the degree of local damage seismic in bolted connections. In this work, a nonlinear time history analysis which takes into account nonlinear modes and frequencies was adopted. According to this approach, the nonlinear modes and frequencies can be determined by an iterative procedure which based on the method of equivalent linearization. The introduction of the notation of nonlinear modes permits an extension of the method of linear modal synthesis to nonlinear cases in order to obtain the dynamic response of nonlinear systems. In another experimental context, this thesis presents the results from shaking table tests of a two-story steel frame with end-plate bolted connections. The aim of the experimental tests is to understand the inelastic behavior of steel frame structures subjected to dynamic loads. Moreover, the purpose of these tests is also to study the changes in modal parameters due to the development of elasto-plastic behavior and low cycle fatigue damage in steel frame connections. A nonlinear numerical simulation of the system is performed based on the developed model and the proposed numerical approach. A comparison of the results obtained from numerical analysis and those of shake table testing is presented. However, the damage analysis for steel frames under random seismic excitations requires the application of an adequate algorithm. An algorithm was developed to assess the seismic performance of steel frames with bolted connections. Using this algorithm, the influence of low cycle fatigue damage in the behavior of end plate bolted connections can be studied.

Liquefaction is a major challenge in geotechnical engineering in which soil strength and stiffness are compromised due to earthquake activity. Understanding and predicting the behaviour and liquefaction susceptibility of soils under cyclic loading is a critical issue in civil engineering, mining and protective engineering. Numerous earthquake-induced ground failure events (e.g., substantial ground deformation, reduced bearing capacity) or liquefaction in natural fine-grained soils or manmade fine-grained soils (i.e., fine tailings) produced by mining activities have been observed and reported in the literature. Tailings are manmade soils that remain following the extraction of metals and minerals from mined ore in a mine processing plant. Traditionally, such tailings are stored in surface tailings impoundments at the mine’s surface. However, geotechnical and environmental risks and consequences related to conventional tailings impoundments have attracted the attention of the engineering community to develop novel methods of tailings disposal and management to minimize geotechnical and environmental risks. Thus, engineers have introduced and implemented innovative tailings technologies—thickened tailings and paste tailings—as cost-effective means for tailings management in mining operations. As both thickened tailings and paste tailings have lower water content and higher solid content than tailings in conventional impoundments, these tailings may be more resistant to liquefaction. However, it should be noted that the seismic or cyclic behaviour of these thickened and paste tailings, with and without heavy rainfall effects, are not fully understood. There is little technical information or data about the behaviour and liquefaction of thickened and paste tailings under seismic or cyclic loading conditions. The objective of the present PhD research is to investigate the response of layered thickened and paste tailings deposits, with and without heavy rainfall effects, to cyclic loads by conducting shaking table tests. To simulate the field deposition of thickened and paste tailings, tailings were deposited in three thin layers in a flexible laminar shear box (FLSB) attached to the shaking table equipment. A sinusoidal seismic loading at a frequency of 1 Hz and peak horizontal acceleration of 0.13g was applied at the bottom of the layered tailings deposits. Acceleration, displacement and pore water pressure responses to the cyclic loading were monitored at the middle depth of each layer of the tailings deposits. Regarding the acceleration response of these thickened and paste tailings deposits (without the effect of heavy rainfall), there was no difference between the middle of the bottom and middle layers or at the base of the shaking table. However, the acceleration at the middle of the top layer differed from the acceleration at the base of the shaking table. Throughout shaking, the layered tailings deposits (with and without the effect of heavy rainfall) exhibited contraction and dilation responses. The excess pore water pressure ratios of the layered thickened tailings deposit that was not exposed to heavy rainfall prior to shaking were found to exceed 1.0 during shaking. However, for the layered paste tailings deposit that was not exposed to the effect of heavy rainfall prior to shaking, the excess pore water pressure ratios were found to be lower than 0.85 during shaking. This reveals that without the effect of heavy rainfall, the layered thickened tailings deposit was susceptible to liquefaction, whereas the layered paste tailings deposit was resistant to liquefaction during shaking. The excess pore water ratios of the layered thickened and the paste tailings deposits that were exposed to heavy rainfall prior to shaking were found to be lower than 0.8 during shaking. This reveals that with the effect of heavy rainfall, the layered thickened and paste tailings deposits were resistant to liquefaction during shaking. The results and findings of this PhD research thus provide valuable information for the implementation of tailings in earthquake-prone areas.

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No description available.

Use of soil retaining walls for roads, embankments and bridges is increasing with time and reinforced soil retaining walls are found to be very efficient even under critical conditions compared to unreinforced walls. They offer competitive solutions to earth retaining problems associated with less space and more loads posed by tremendous growth in infrastructure, in addition to the advantages in ease and cost of construction compared to conventional retaining wall systems. The study of seismic performance of reinforced soil retaining walls is receiving much attention in the light of lessons learned from past failures of conventional retaining walls. Laboratory model studies on these walls under controlled seismic loading conditions help to understand better how these walls actually behave during earthquakes. The objective of the present study is to investigate the seismic response of geosynthetic reinforced soil wall models through shaking table tests. To achieve this, wrap faced and rigid faced reinforced soil retaining walls of size 750 × 500 mm in plan and 600 mm height are built in rigid and flexible containers and tested under controlled dynamic conditions using a uni-axial shaking table. The effects of frequency and acceleration of the base motion, surcharge pressure on the crest, number of reinforcing layers, container boundary, wall structure and reinforcement layout on the seismic performance of the retaining walls are studied through systematic series of shaking table tests. Results are analyzed to understand the effect of each of the considered parameters on the face displacements, acceleration amplifications and soil pressures on facing at different elevations of the walls. A numerical model is developed to simulate the shaking table tests on wrap faced reinforced soil walls using a computer program FLAC (Fast Lagrangian Analysis of Continua). The experimental data are used to validate the numerical model and parametric studies are carried out on 6 m height full-scale wall using this model. Thus, the study deals with the shaking table tests, dynamic response of reinforced walls and their numerical simulation. The thesis presents detailed description of various features and various parts of the shaking table facility along with the instrumentation and model containers. Methodology adopted for the construction of reinforced soil model walls and testing procedures are briefly described. Scaling and stability issues related to the model wall size and reinforcement strength are also discussed. From the study, it is observed that the displacements are decreasing with the increase in relative density of backfill, increase in surcharge pressure and increase in number of reinforcing layers; In general, accelerations are amplified to the most at the top of the wall; Behaviour of model walls is sensitive to model container boundary. The frequency content is very important parameter affecting the model response. Further, it is noticed that the face displacements are significantly affected by all of the above parameters, while the accelerations are less sensitive to reinforcement parameters. Even very low strength geonet and geotextile are able to reduce the displacements by 75% compared to unreinforced wall. The strain levels in the reinforcing elements are observed to be very low, in the order of ±150 micro strains. A random dynamic event is also used in one of the model tests and the resulted accelerations and displacements are presented. Numerical parametric studies provided important insight into the behaviour of wrap faced walls under various seismic loading conditions and variation in physical parameters.

Οι κατασκευές εδαφικής αντιστήριξης εξακολουθούν να βρίσκονται σε ευρύτατη χρήση, με διαρκώς αυξανόμενο ενδιαφέρον λόγω των απαιτήσεων των σύγχρονων έργων υποδομής αλλά και των αναγκών δόμησης σε πυκνό αστικό περιβάλλον. Το ενδιαφέρον εστιάζεται σε κατασκευαστικές λύσεις και μεθόδους σχεδιασμού που συνδυάζουν ασφάλεια και οικονομία. Η ανάλυση των συγκεκριμένων κατασκευών αντιμετωπίζει πλήθος δυσεπίλυτων προβλημάτων στο αντικείμενο της αλληλεπίδρασης εδάφους-κατασκευής που συχνά καθορίζουν τη συμπεριφορά του έργου. Η κατανόηση αυτών των μηχανισμών επιτρέπει το σχεδιασμό με μικρότερα περιθώρια αβεβαιότητας που οδηγούν σε οικονομικότερες και ορθολογικότερες λύσεις. Στην κατεύθυνση αυτή συμβάλει η παρούσα Διατριβή, με την ανάπτυξη αναλυτικών εργαλείων και θεωρητικών ευρημάτων που βοηθούν στην κατανόηση των μηχανισμών της αλληλεπίδρασης και στην εκτίμηση της συμπεριφοράς των τοίχων αντιστήριξης υπό συνδυασμένη βαρυτική και σεισμική φόρτιση. Έμφαση δίνεται στην παραγωγή απλών κλειστών λύσεων και μεθοδολογιών για τον υπολογισμό των εδαφικών ωθήσεων και τη στατική ανάλυση του συστήματος τοίχου εδάφους. Συγκεκριμένα, παράγονται λύσεις άνω και κάτω ορίου για ενδόσιμους τοίχους, οι οποίες, παρότι προσεγγιστικές, πλεονεκτούν έναντι των κλασικών εξισώσεων Coulomb και Mononobe-Okabe τις οποίες μπορούν να αντικαταστήσουν. Σε ειδικές περιπτώσεις, όπως η περίπτωση τοίχων προβόλων με πεπλατυσμένο πέλμα, οι προτεινόμενες λύσεις οδηγούν σε ακριβή αποτελέσματα που βασίζονται σε ένα γενικευμένο πεδίο τάσεων Rankine. Επίσης παρουσιάζονται επεκτάσεις τους οι οποίες επιτρέπουν τον υπολογισμό μη-υδροστατικών κατανομών ωθήσεων γαιών λαμβάνοντας υπόψη την κυματική διάδοση της σεισμικής διέγερσης στο επίχωμα, σύμφωνα με μια ορθότερη παραλλαγή της ιδέας των Steedman & Zeng και τις διαφορετικές κινηματικές συνθήκες που προέρχονται από την απόκριση του τοίχου με περιστροφή περί την κορυφή ή τη βάση σύμφωνα με την τεχνική της Dubrova. Για την περίπτωση ανένδοτων τοίχων παρουσιάζεται μεθοδολογία για τη δραστική απλοποίηση των διαθέσιμων ελαστοδυναμικών, κυματικών λύσεων, όπως αυτή των Veletsos & Younan, η οποία καταλήγει σε κλειστές μαθηματικές εκφράσεις για τον υπολογισμό των ωθήσεων. Τέλος, παρουσιάζονται νέα ευρήματα στην κατεύθυνση της μαθηματικής αντιμετώπισης του δυσεπίλυτου προβλήματος της οριακής ισορροπίας ριπιδίου τάσεων σε εδαφικό μέσο στο οποίο ενεργούν βαρυτικές και αδρανειακές δυνάμεις πεδίου. Η παρούσα εργασία συμβάλλει στην περαιτέρω διερεύνηση του προβλήματος το οποίο θεμελίωσαν θεωρητικά οι Levy, Boussinesq, von Karman και Caquot, μέσω της δραστικής (αλλά ακριβούς) απλοποίησης του σε μία μη-γραμμική συνήθη διαφορική εξίσωση, η οποία επιτρέπει την επίλυση με απλές αριθμητικές και ημιαναλυτικές τεχνικές. Πέρα από τα ακριβή αριθμητικά αποτελέσματα, η προτεινόμενη ανάλυση προσφέρει μια βαθύτερη εποπτεία στο πρόβλημα και ανοίγει το δρόμο για περαιτέρω διερεύνηση ή και επέκταση της μεθόδου πέρα από τα όρια της κλασικής οριακής ανάλυσης. Η αξιοπιστία των προτεινόμενων λύσεων ελέγχεται μέσω συγκρίσεων με καθιερωμένες λύσεις και πειραματικά δεδομένα από τη βιβλιογραφία, αλλά και πρόσφατα πειραματικά αποτελέσματα που παρήχθησαν από τον συγγραφέα και ερευνητές στη σεισμική τράπεζα του Πανεπιστημίου του Bristol του Ηνωμένου Βασιλείου. / Earth retaining structures are still in widespread use, with growing interest due to the demands of modern infrastructure and building needs in a dense urban environment. Building solutions and design methodologies that combine safety and economy are the objectives of modern research. Significant difficulties in the analysis of retaining structures arise from the soil-structure interaction nature of the problem that often prescribes its behavior. Understanding these mechanisms allows design under smaller uncertainties, leading to economical and rational solutions. The contribution of the present thesis consists of the development of analytical tools and theoretical findings, helpful in understanding the mechanisms of interaction and the behavior of walls under combined gravity and seismic loading. Emphasis is given to the derivation of simple closed-form solutions and methodologies for the calculation of earth pressures and the static analysis of wall-soil system. Specifically, approximate Lower and Upper Bound solutions are produced for the case of yielding walls, which are advantageous compared to the classical equations Coulomb and Mononobe-Okabe. In special cases, such as the L-shaped cantilever walls, these solutions lead to exact results, pertaining to a generalized Rankine stress field. Extensions of the above solutions are presented allowing the calculation of non-hydrostatic earth pressure distributions, due to the wave propagation of the seismic excitation in the backfill, according to a better variant of the Steedman & Zeng approach and different kinematic conditions of the wall rotating around the top or bottom, according to the technique of Dubrova. For the case of non-yielding walls, a new methodology for the drastic simplification of available wave solutions, such as the Veletsos & Younan, is presented which leads to closed-form expressions for the dynamic pressure calculation. Finally, new theoretical findings are presented for the mathematical treatment of the intractable problem of plastic limit equilibrium in soil medium subjected to gravitational and inertial forces field. This work contributes to the further investigation of the problem which is founded theoretically by Levy, Boussinesq, von Karman and Caquot, through the significant (but accurate) simplification to a single, non-linear ordinary differential equation, easier to handle by simple numerical and semi-analytical techniques. Apart from the exact numerical results, the proposed analysis provides a deeper physical insight, leading the way to further investigation or extension of the method beyond the classical limit analysis assumptions. The reliability of the proposed solutions is checked through comparisons with established solutions and experimental data from the literature and recent experimental results obtained by the author and researchers in the shake table laboratory of the University of Bristol, UK.

Les séismes constituent une source d’aléas importante pour l’étude de la vulnérabilité d’unbâtiment. Le comportement parasismique des bâtiments à ossatures en bois est particulièrementintéressant. Deux familles de structure à ossature en bois peuvent être distinguées : les ossaturesutilisant les produits industriels que sont les panneaux en bois reconstitué servant à contreventerla structure et les connecteurs métalliques, et les ossatures traditionnelles avec remplissage reposantsur des techniques de construction anciennes et dépendantes du contexte local. L’efficacitédu comportement parasismique des bâtiments à ossature en bois traditionnels avec remplissagereste encore peu reconnue en raison du manque de résultats issus des travaux de recherche.Les travaux présentés dans cette thèse visent ainsi à améliorer les connaissances sur le comportementparasismique de cette typologie constructive. Partant de l’hypothèse selon laquellece comportement est gouverné par la réponse des assemblages par connecteurs métalliques, uneapproche multi-échelles, couplant études expérimentales et études numériques est développée.Elle détaille l’analyse à l’échelle 1 de la connexion, en passant par l’échelle 2 des cellules élémentaires,constitutives des murs, par l’échelle 3 des murs de contreventement pour se finaliserà l’échelle 4 du bâtiment dans son ensemble.Sur le plan expérimental, cette approche permet d’une part, de réaliser des études paramétriqueset ainsi d’appréhender l’influence de la réponse de chaque élément (bois, clous, feuillard,remplissage, contreventement, ouvertures) sur le comportement local (échelles 1 et 2) et global(échelles 3 et 4) de la structure. D’autre part, elle permet de fournir une base de données pourla validation des modélisations numériques aux différentes échelles.Sur le plan de la modélisation numérique, cette approche multi-échelles est fondée sur la priseen compte du comportement non-linéaire hystérétique des assemblages à l’échelle supérieure, parl’intermédiaire d’un macro-élément, développé dans la cadre de la méthode des éléments finis.Ainsi, grâce à une modélisation simplifiée (assemblage des macro-éléments), le calcul est rapide,aussi bien à l’échelle du mur qu’à celle du bâtiment, et intègre les phénomènes non-linéaire locaux.Le modèle peut ainsi prédire de manière relativement précise le comportement dynamique de lastructure complète à l’échelle 4, testée sur table vibrante.L’étude présentée dans ce manuscrit fait partie des travaux précurseurs relatifs à l’analysede la vulnérabilité sismique des ossatures bois avec remplissage. Cette étude débouche sur denombreuses perspectives pour l’analyse de cette typologie constructive. Elle confirme que les bâtimentsà ossatures en bois avec remplissage ont un comportement parasismique très performant. / The seismic vulnerabilty is an important issue in the design of a building. The seismicresistant behavior of timber-framed structures is particularly relevant. Two types of timberframedstructures can be distinguished : the timber-framed structures using industrial products,such as wood-products panels used to brace the structure or metal fasteners, and traditionaltimber-framed structures included infill made of natuarl materials (earth or stones masonry).The seismic resistant behavior efficiency of traditional structures remains poorly recognizedbecause of the lack of research results on this kind of construction.Therefore, the thesis aims at improving the seismic behavior knowledge of timber-framedmasonry. Based on the assumption that their behavior is driven by the response of the metalfasteners connections, a multi-scale approach is proposed. It couples experimental and numericalstudies. At the scale 1 of the connection, at the scale 2 of the elementary constitutive cell ofwalls, at the scale 3 of structural elements such as shear walls and finally at the scale 4 of theentire building.In regards to the experimental work, this method allows, on the one hand, to perform parametricstudies and to analyze the influence of each element (wood member, nails, steel strip,infill, bracing, openings) on the local behavior (scales 1 and 2) and on the global behavior(scales 3 and 4) of the structure. On the other hand, it allows to provide a database to validatethe numerical modeling at each scale.In regards to the numerical work, this multi-scale approach allows to take into account thehysteretic behavior of joints in the development of a macro-element at the scale 2. Thus, thanksto a simplified finite element modeling (macro-element assembly), the computational cost islimited and it allows to take into account the local phenomena. The model is able to predictrelatively accurately the dynamic behavior at the scale 4 of the building, tested on a shakingtable.The study, presented herein, is one of the pioneer work that deals with the analysis of theseismic vulnerability of timber-framed structures with infill panels. This study provides outlookfor the analysis of this type of buildings. It confirms that the timbered masonry structures havea relevant seismic resistant behavior.

No description available.