Esta dissertação apresenta em primeira etapa o trabalho desenvolvido para averiguar a adequação dos modelos reológicos de Mohr-Coulomb e de Endurecimento de solo, para representar as deformações e distorções que ocorrem no sistema soloestrutura, quando do processo de escavação de valas escoradas. Além disto, em uma segunda etapa fazem-se estimativas de previsão de danos causados em edificações, em decorrência das escavações de uma vala escorada da linha 1 do Metropolitano de São Paulo (Metrô S.P.). A primeira e a segunda etapa foram feitas através de 810 simulações numéricas, em elementos finitos utilizando-se o software PLAXIS, associadas a retroanálise por processo direto do módulo de deformabilidade a 50% da tensão de ruptura dos solos utilizando-se para isto o processo direto. Apresenta-se também uma síntese da formação e dos tipos de solos que constituem a bacia sedimentar de São Paulo, onde se localiza a seção experimental nº1 objeto de estudo desta dissertação. Faz-se uma breve revisão bibliográfica a respeito das técnicas de retroanálise. Apresentam-se critérios para escolha de intervalos de parâmetros geotécnicos que representem o sistema solo-estrutura no processo de escavação. Foram feitas análises paramétricas para determinar os parâmetros geotécnicos que mais influenciam o sistema solo-estrutura. Comparam-se os modelos constitutivos de Mohr-Coulomb e de endurecimento na previsão das deformações. Por fim, faz-se a previsão do nível de danos causados pelas escavações da vala, a um edifício hipotético / This dissertation presents, in a first part, the work done to verify how appropriate are the Mohr-Coulomb and hardening soil constitutive models to represent the strains and the distortions associated with escavations of braced wall process. In the second part, estimates are made of the damages in constructions due to the braced excavations of line one of Sao Paulo Subway (Metrô S.P.). In the two phases, 810 numeric simulations were made, in finite elements using the software PLAXIS, associated the back analysis for direct process. It is presented a synthesis of the formation and the types of soils that constitute the basin of the sediments of the city of São Paulo, where is located the section experimental nº1, object of study of this dissertation. It is presented an short bibliographical revision regarding the back analysis techniques. Criteria for choice of intervals of parameters geotechnical that represent the system soil-structure in the excavation process are presented. Parametric analyses are made to determine which the parameters have larger influence in the behavior of the system soil-structure. The behavior of the soil-structure system is simulated using the Mohr-Coulomb and hardening soil constitutive models. The Mohr-Coulomb and hardening soil constitutive models are compared in the forecast of the deformations. Finally, it is made the forecast of the level of damages to a hypothetical building caused by the braced excavations

The focus of this thesis is to deal with reverse engineering of high-rise building settlements. This is modeled via the finite element method performed in the Plaxis 3D program. In the first part of this thesis, a calibration of input parameters of an appropriate material model – Hardening soil – is conducted. This calibration is a result of oedometric test data which were obtained within a geotechnical survey. An influence of soils over consolidation affecting calibration and the material model choice is described. Final values of reference stiffness parameters are used in a mathematical model of the focused area. This model is created for one half of the high-rise building plan, including vestibule. The high-rise building is founded in a foundation pit. The foundations of this building consist of raft foundation and piles of jet grouting. In the model, there are also changes in pore pressure during an excavation of foundation pit included. The functional model is used for parametric analyses, namely examining cases of object´s foundations and the possible influence of foundation pit´s symmetry on the object´s settlement. All the calculated processes in the object´s settlements are then compared to data obtained from geotechnical monitoring of the structure.

<p>A procedure for calibrating a discrete element (DE) computational soil model for various moisture contents using a conventional Asperity-Spring friction modeling technique is presented in this thesis. The procedure is based on the outcomes of two physical soil experiments:</p> <p>(1) Compression and (2) unconfined shear strength at various levels of normal stress and normal pre-stress. The Compression test is used to calibrate the DE soil plastic strain and elastic strain as a function of Compressive stress. To calibrate the DE inter-particle friction coefficient and adhesion stress as a function of soil plastic strain, the unconfined shear test is used. This thesis describes the experimental test devices and test procedures used to perform the physical terramechanical experiments. The calibration procedure for the DE soil model is demonstrated in this thesis using two types of soil: sand-silt (2NS Sand) and silt-clay(Fine Grain Soil) over 5 different moisture contents: 0%, 4%, 8%, 12%, and 16%. The DE based models response are then validated by comparing them to experimental pressure-sinkage results for circular disks and cones for those two types of soil over 5 different moisture contents. The Mean Absolute  Percentage Error (MAPE) during the compression calibration was 26.9% whereas during the unconfined shear calibration, the MAPE was calculated to be 11.38%. Hence, the overall MAPE was calculated to be 19.34% for the entire calibration phase.</p>