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ABSTRACT COMPARISON OF ANALYSIS METHODS OF EMBEDDED RETAINING WALLS HARMANDAR, Serkan M.S., Department of Civil Engineering Supervisor : Prof. Dr. Yener &Ouml / zkan Co -Supervisor : Dr. Oguz &Ccedil / aliSan December 2006, 123 pages In this study a single-propped embedded retaining wall supporting a cohesionless soil is investigated by four approaches, namely limit equilibrium, subgrade reaction, pseudo-finite element and finite element methods. Structural forces, such as strut loads, wall shear forces, bending moments are calculated by each method and results are compared. The analyses are carried for for three values of internal friction angle of soil / 30o, 35o, and 40o. Effects of modulus of soil elasticity of the backfill and wall stiffness on structural forces are investigated by using different values for these parameters. It is found that, in those of obtained by, limit equilibrium approach results in embedment depth greater than other methods. Minimum strut loads for the same soil and structure parameters are obtained by limit equilibrium method. An increase of Young&rsquo / s modulus of the soil results in decrease of the strut loads.

Despite the crucial role they play in transferring loads from the superstructure to the foundation, steel column-to-footing connections have received little attention in research. Though shallow embedded connections are typically characterized as pinned, studies have shown that they exhibit significant rotational stiffness. The objective of this thesis is to quantify the rotational stiffness of such connections. A method named the continuum model is developed by which the rotational stiffness of embedded connections may be calculated. Outputs from this model are compared with experimental data on steel connections embedded in concrete. The continuum model is shown to be capable of reasonably predicting the rotational stiffness of such connections. Results from the model were consistent with those of previous experimental studies that showed that embedment lengths greater than twice the column depth fail to significantly increase stiffness. Plots of rotational stiffness vs. embedment length developed from the continuum model are provided such that rotational stiffness may be calculated for any wide flange shape at any embedment length. Simplified equations provide a simpler way for engineers to estimate the same information.

In this study, a typical mat foundation and structural loading pattern is considered. Three dimensional finite element analyses, PLAXIS 3D, is performed to determine the soil / foundation contact stress distribution, settlement distribution, distribution of modulus of subgrade reaction as a function of column spacing, stiffness of the soil and thickness of the foundation. A parametric study is performed to demonstrate the dependence of those distributions on various parameters. Moreover, a relationship between size of the foundation, deformation modulus of foundation soil and modulus of subgrade reaction is proposed. Depending on the variations in those parameters, obtained shear force and bending moment distributions are compared. Consistency between the resulting shear forces and bending moments of a typical foundation, modeled in two different three dimensional finite element programs, PLAXIS 3D and SAP 2000, is discussed. It is found that the variation in the aforementioned parameters cause different influences on contact stress distribution, settlement distribution, distribution of modulus of subgrade reaction. The importance of those variations in beforementioned parameters, under different situations is discussed. A relationship between modulus of subgrade reaction and deformation modulus of foundation soil is proposed.

Este trabalho parte de um acervo pré-existente de provas de carga em placa (segundo os procedimentos ABNT-NBR-6489 e ASTM-D-1196) em solos da Formação Guabirotuba, importante unidade geológica da região metropolitana de Curitiba. O objetivo do trabalho é favorecer o entendimento destes solos no que diz respeito à sua competência como subleito para pavimentos industriais rígidos. É realizada uma revisão sobre modelos de fundação de pavimento, aspectos geológicos e geotécnicos da Formação Guabirotuba, e métodos de determinação do coeficiente de recalque. A análise baseia-se no coeficiente de recalque \"k\" obtido em trinta e duas provas de carga em placa e utiliza uma classificação prática dos solos, quanto ao seu nível de intemperismo: argilas cinzas \"inalteradas\", argilas vermelhas \"laterizadas\" e argilas variegadas \"intemperizadas\", as quais mostram valores decrescentes de coeficiente de recalque, nessa ordem. Notou-se que algumas correlações existentes na literatura permitiram obter razoáveis previsões do coeficiente de recalque, como aquelas baseadas em valores de SPT e de CBR. Os valores de coeficiente de recalque medidos para estes solos mostram-se superiores àqueles sugeridos por tabelas práticas. Devido à variabilidade de resultados encontrada e à influência do subleito no desempenho final do sistema de fundação, fica evidenciada a importância da realização de provas de carga em placa para obtenção dos parâmetros de dimensionamento de pavimentos industriais rígidos. / The present work employs a data base of plate load tests (performed according the ABNT-NBR-6489 and ASTM-D-1196 procedures) in soils of the Guabirotuba Formation, important geological unit of Curitiba metropolitan region. The purpose of the work is the improving of the knowledge of these soils related to their behavior as subgrade for rigid industrial pavements. It is provided a revision about pavements foundation models, geological and geotechnical aspects of the Guabirotuba Formation and methods of the determination of the modulus of subgrade reaction. The analysis is based on the modulus of subgrade reaction \"k\" from 32 plate loading tests and uses a practical classification of the soils, according to their weathering level: intact gray clays, lateritic red clays and weathered variagate clays that showed a derease of the modulus in this order. Some correlations were found to predict fair values of \"k\", such as those based on SPT and on DCP. It was also noticed that the values of the modulus of subgrade reaction obtained are higher than the usual recommendations of the literature. The variability and the influence of the subgrade in the final performance of the pavaments make evident the importance of the plate load tests for obtaining reliable design parameters.

Šiame darbe susisteminti ir palyginti pagrindiniai grunto standumo koeficientų nustatymo metodai. Aprašoma metodika, kaip iš grunto santykinio tankio galima apskaičiuoti dinaminį bei statinį tamprumo modulius. Pateikiamos šių grunto parametrų koreliacinės priklausomybės. Eksperimentiniais tyrimais įrodyta, kad silpnuose gruntuose egzistuoja netiesinė grunto tamprumo modulio priklausomybė nuo šalia grunto esančios priekrovos. Priekrovą traktuojant kaip tiesiškai priklausančią nuo gylio, išvesta tamprumo modulio silpnuose gruntuose priklausomybė nuo gylio. Rezervuarų skaičiavimui buvo pasinaudota 2 panašių konstrukcijų skaičiavimo metodikomis (tunelių metodika bei vamzdžių m.). Taip pat pasinaudota СНиП 2.06.09-84 tunelių projektavimo nurodymais. Konstrukcija sumodeliuota projektavimo programomis Robot Structural Analysis Pro, SCAD, Plaxis 2D. Taip pat pateiktas patobulintas modelis, atramas išskirstant į ploto vienetą, autoriaus nuomone, tinkamesnėmis plonasienėms mažo standumo konstrukcijoms. Skaičiuotiniuose modeliuose įvertinami visi pagrindiniai rezervuarų konstrukciniai elementai: galiniai kupolai, lengvosios sąstandos, špangautai. Laboratoriniais bandymais nustatytos ir įvertintos polimerinio kompozito konstrukcinės savybės: virtualus tamprumo modulis, Puasono koeficientas, valkšnumo koeficientas bei senėjimo faktorius. Išvadose apibendrinami rezultatai, taip pat suformuojami pasiūlymai, naudingi tolesniems tiriamiesiems darbams, bei panašių konstrukcijų... [toliau žr. visą tekstą] / Main methods to determine subgrade reaction is systemized in this master thesis work. Determination of static and dynamic deformation modulus, when relative soil density is known, are also familiarized. Correlation between the parameters is given in section 2. Experiments were made to prove that there is a link between deformation modulus and surcharge. If surcharge depends linearly from depth, then a function was created to predict deformation modulus values in weak soil when depth varies. 2 similar construction (pipes and tunnels) methods were used to design a buried tank. Design model was created by these design programs: Robot Structural Analysis Pro, SCAD, and PLAXIS 2D. An additional tank modelling method has been suggested by the author. Supports were assigned in plane instead of in a straight line. The updated model seems to better fit for low stiffness construction materials like GRP composites. In these design models all common tank structural elements were included: longitude domes, light and heavy stiffeners, orthotropic material. Main design parameters like virtual elastic modulus, Poisson ratio, creep factor, factor of durability. Results are summarized in conclusions. Suggestions were provided to help future researchers and designers with this kind of problems: structural design of composite polymer structures, design of buried thin-shelled tanks and evaluation of deformation modulus.

Made available in DSpace on 2014-12-17T14:48:16Z (GMT). No. of bitstreams: 1 ArthurGDA_DISSERT.pdf: 3193366 bytes, checksum: 6e05d0803e66a8ae37a24358be586be8 (MD5) Previous issue date: 2013-12-10 / An experimental study has been conducted to investigate the behavior of continuous flight auger (cfa) bored piles and metalic driven H-section piles under lateral loading in cohesionless soils. The piles were tested in two different areas at the same site. Both areas consisted of a 3-m thick compacted superficial fill of pure fine sand, underlain by layers of naturally occurring pure fine-thick sand. Fills are differentiated by the relative densities which were compressed, 45% e 70%, respectively. Each area received one identical pair of cfa piles and two identical pairs of H-piles. A static lateral loading test was performed in each pair of piles. In this work, the pile load test results are reported and interpreted. The horizontal coefficient of subgrade reaction was determined from the results of the loading tests and compared with values determined by correlations based on penetration resistance index of SPT tests (NSPT). p-y formulations describing the static behavior of the piles were applied to the problem under evaluation. Back Analyses were made through theoretical and experimental p-y curves for obtaining input parameters for the analytic models, among which the coefficient of horizontal reaction. The soil pile system horizontal loading at rupture was determined by the theoretical methods and the results were compared with the experimental results, checking its validity / Um estudo experimental foi realizado para investigar o comportamento de estacas escavadas h?lice cont?nua e estacas cravadas met?licas submetidas a carregamentos laterais em areia. As estacas foram ensaiadas em duas ?reas diferentes no mesmo local. Ambas as ?reas eram compostas por um aterro superficial de 3 m de espessura de areia fina, seguido de camadas naturais de areia fina a grossa. Os aterros diferenciam-se pela densidade relativa com que foram compactados, 45% e 70%, respectivamente. Cada ?rea recebeu um par id?ntico de estacas h?lice cont?nua e dois pares id?nticos de estacas met?licas com perfil H . Em cada par de estacas foi executada uma prova de carga est?tica. Neste trabalho, os resultados das provas de carga s?o apresentados e interpretados. O coeficiente de rea??o horizontal do solo foi determinado atrav?s dos resultados das provas de carga e comparado com valores obtidos a partir de correla??es baseadas no ?ndice de resist?ncia ? penetra??o do ensaio SPT (NSPT). Curvas p-y foram constru?das para prever o comportamento de estacas submetidas a carregamentos horizontais. Retro an?lises foram efetuadas atrav?s das curvas p-y te?ricas e experimentais para obten??o de par?metros de entrada para os modelos anal?ticos, dentre os quais o coeficiente de rea??o horizontal. A carga de ruptura do sistema solo estaca foi determinada atrav?s de m?todos te?ricos e os resultados foram comparados com os resultados experimentais, verificando sua validade

Este trabalho parte de um acervo pré-existente de provas de carga em placa (segundo os procedimentos ABNT-NBR-6489 e ASTM-D-1196) em solos da Formação Guabirotuba, importante unidade geológica da região metropolitana de Curitiba. O objetivo do trabalho é favorecer o entendimento destes solos no que diz respeito à sua competência como subleito para pavimentos industriais rígidos. É realizada uma revisão sobre modelos de fundação de pavimento, aspectos geológicos e geotécnicos da Formação Guabirotuba, e métodos de determinação do coeficiente de recalque. A análise baseia-se no coeficiente de recalque \"k\" obtido em trinta e duas provas de carga em placa e utiliza uma classificação prática dos solos, quanto ao seu nível de intemperismo: argilas cinzas \"inalteradas\", argilas vermelhas \"laterizadas\" e argilas variegadas \"intemperizadas\", as quais mostram valores decrescentes de coeficiente de recalque, nessa ordem. Notou-se que algumas correlações existentes na literatura permitiram obter razoáveis previsões do coeficiente de recalque, como aquelas baseadas em valores de SPT e de CBR. Os valores de coeficiente de recalque medidos para estes solos mostram-se superiores àqueles sugeridos por tabelas práticas. Devido à variabilidade de resultados encontrada e à influência do subleito no desempenho final do sistema de fundação, fica evidenciada a importância da realização de provas de carga em placa para obtenção dos parâmetros de dimensionamento de pavimentos industriais rígidos. / The present work employs a data base of plate load tests (performed according the ABNT-NBR-6489 and ASTM-D-1196 procedures) in soils of the Guabirotuba Formation, important geological unit of Curitiba metropolitan region. The purpose of the work is the improving of the knowledge of these soils related to their behavior as subgrade for rigid industrial pavements. It is provided a revision about pavements foundation models, geological and geotechnical aspects of the Guabirotuba Formation and methods of the determination of the modulus of subgrade reaction. The analysis is based on the modulus of subgrade reaction \"k\" from 32 plate loading tests and uses a practical classification of the soils, according to their weathering level: intact gray clays, lateritic red clays and weathered variagate clays that showed a derease of the modulus in this order. Some correlations were found to predict fair values of \"k\", such as those based on SPT and on DCP. It was also noticed that the values of the modulus of subgrade reaction obtained are higher than the usual recommendations of the literature. The variability and the influence of the subgrade in the final performance of the pavaments make evident the importance of the plate load tests for obtaining reliable design parameters.

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