This thesis includes experimental and theoretical work performed to investigate the behaviour of ground anchors in sand. The anchor footing used was a circular plate connected to a tie rod. The experimental work was carried out by installing the anchor in a l830mm x 1830mm x l220mm deep tank containing dry sand. The sand sample was prepared by using a vibrator fixed to the bottom of the tank. The anchor was pulled out at a constant rate of strain and the load-displacement curve was recorded on a plotter. The vibration of the tank was defined by deter.mining the acceleratton and amplitude of the motion in the horizontal and vertical directions. A density tube and a hydraulic gauge were designed to investigate the distribution of stresses in sand. The variation of the vibration time, the constant rate of strain, the shaf V plate diameter, the plate thickness/plate diameter, and the boundary distance with the load-displacement curve were also investigated. The load-displacement curve of different diameter plates embedded at various depths for different times of vibration were recorded. To investigate the behaviour of ground anchors theoretically, the finite element technique was used and a computer progra~ developed. A linear stress-strain relationship was used to predj.ct and investigate the behaviour of the anchor. A non-linear stress-strain relationship and a failure criterion were also used to predict the load-displacement curve of the vertical anchor. The effect of the parameters which were investigated experimentally were also examined. The distribution of the load on the anchor plate and the extent of the failure zone were plotted. The predicted and experimental results in this thesis were compared with laboratory and field results obtained by previous researchers.

No description available.

O evento de previsões do comportamento carga-recalque de uma estaca executada em solo predominantemente arenoso foi apresentado no 8° Seminário de Engenharia de Fundações Especiais e Geotecnia (SEFE8). As previsões utilizaram sondagens CPT, DMT e SPT realizadas no campo experimental de Araquari, em Santa Catarina. A estaca utilizada para o evento foi do tipo escavada com polímero, diâmetro de 100cm e comprimento de 24m. Foram recebidos pelo comitê organizador 73 previsões provenientes de 20 países, com estimativas do comportamento carga-recalque da estaca, da capacidade de carga total, lateral e de ponta e a distribuição de carga ao longo do fuste até a ruptura, definida pelo recalque de 100 mm (w/D = 10%), com um resumo dos métodos e considerações. Os dados das previsões foram comparados aos resultados obtidos em campo pela prova de carga estática da estaca instrumentada. As previsões foram majoritariamente conservadoras e o ensaio mais utilizado para determinação dos parâmetros do solo foi o CPT, tanto no meio acadêmico quanto no prático Diversos métodos foram utilizados, porém mesmo previsões que utilizaram o mesmo método apresentaram variabilidades nos resultados. Baixos valores de desvio na capacidade de carga total não significaram pequenos desvios de lateral e de ponta, mas uma combinação de desvios positivos e negativos desses. A maioria das estimativas subestimou a capacidade lateral e superestimou a de ponta. O método de Verbrugge (1981) foi utilizado em duas das cinco previsões com menores desvios de capacidade total. As curvas carga-recalque e carga-profundidade foram avaliadas quanto aos desvios médios absolutos e formatos, dados pela variância. As curvas carga-recalque com médias de até 10% utilizaram Elementos Finitos e o software UniPile, e o menor valor de variância utilizou Verbrugge (1981). As curvas carga-profundidade com médias de até 10% utilizaram Verbrugge (1981), Randolph e Wroth (1978) e Gwizdala e Steczniewski (2003), e o menor valor de variância utilizou o software UniPile. / The prediction event of load-settlement behavior of a pile built in predominantly sandy soil was presented at the 8th Foundation Engineering Seminar and Special Geotechnical (SEFE8). The predictions used tests of CPT, DMT and SPT accomplished in Araquari experimental field, in Santa Catarina. A bored pile with polymer, diameter of 100cm and length of 24m was the subject of the event. The organizing committee received 73 predictions from 20 countries, with estimates of load-settlement behavior of the pile, the total, shaft and base load capacity and the load distribution along the shaft until failure, defined by settlement of 100 mm (W/D = 10%), with a brief description of methods and considerations. Data from the predictions were compared to the results obtained in the field by static load test of the instrumented pile. The predictions were mostly conservative and the test most used for soil parameters prediction was the CPT, both in academia as in practice. Several methods were used, but even predictions that used the same method showed variability in the results Low error values in the total load capacity not meant small shaft and base errors, but a combination of positive and negative errors of these. Most estimates underestimated the shaft capacity and overestimated the base. The Verbrugge (1981) method was used in two of five predictions with lower errors of total capacity. The curves were analyzed for absolute average deviation and formats, evaluated by the variance. The load-settlement distribution with average up to 10% used Finite Element and UniPile software, and the lowest value of variance used Verbrugge (1981). The load-depth distribution with average up to 10% used Verbrugge (1981), Randolph and Wroth (1978) and Gwizdala and Steczniewski (2003), and the lowest value of variance used the UniPile software.

Soils, like several other materials, exhibit strong time-dependent behaviour which can be evidenced in terms of creep or strain-rate effects. The degree of this rheological behaviour varies with the type of soil, its structure, and with the stress history. This effect is exacerbated in pile load testing where the procedure duration tends to be shortened under increasing time pressures. The modelling needed to interpret the results therefore becomes more and more complex, including soil viscosity, wave radiation into the soil and other significant phenomena. The objective of the research reported herein is to refine the rheological parameters characterizing the influence of the loading rate within the framework of a relevant pile/soil interaction model fed with dynamic measurements acquired during pile Dynamic Load Tests (DLTs). The final goal is to predict and simulate the quasi-static pile load settlement curve. The pile/soil interaction system is described by a non-linear mass/spring/dashpot system supposed to represent the pile and the soil, with constitutive relationships existing within and between them. These relationships account for the static and the dynamic or rheologic behaviour. A back-analysis process based on a matching procedure between measured and computed quantities allows one to characterize the pile/soil interaction in terms of constitutive and rheologic parameters based on the dynamic measurements. After optimisation of the matching procedure, the parameters obtained are used to simulate the “static” load-settlement curve. The matching procedure is based on an automatic and stochastic parameter perturbation analysis. Since the parameters influence the system response with a relative weight, they are sorted in order to optimise all the parameters by successively retrieving the most influential ones and working on the remaining ones. The back-analysis performed on real dynamic measurements in this research leads to an improved pile/soil interaction model. The slippage between pile and soil along the pile shaft must be explicitly taken into account. This refinement increases the number of degrees of freedom needed to describe the pile/soil system but brings deeper insight into the behaviour of an interfacing zone of limited thickness surrounding the pile shaft.

Title from PDF of title page. / Document formatted into pages; contains 161 pages. / Thesis (M.S.C.E.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: Driving piles constitute a large portion of the high-capacity foundations used today. They transfer structural loads to deep bearing strata when adequate surficial soils are not available. The mechanisms required to install these piles generally consist of a hammer, hammer lead, a crane, and various support rigging. This study focused on lead sections, specifically, one which was manufactured by Berminghammer Foundation Equipment, Inc. The dimensions and strength of a lead section must be capable of supporting both the pile driving hammer and the longest anticipated pile for a given site. The strength of the section must be capable of withstanding hundreds of tons in compression and bending. If the lead is operated in a batter, (tilted forward, backward, or sideways) the weight of the hammer and pile causes much more bending than the vertical orientation. / ABSTRACT: The cross-section details for these long steel sections vary from design to design but usually incorporate some form of bolt group, pins, and steel alignment dowels. This thesis focuses on the design, modeling, and testing of such a connection. The motivation of the study stems from a company-wide incentive to standardize the connections used to splice the Berminghammer C15-series lead section. In an effort to verify a proposed connection design, Berminghammer Foundation Engineering solicited the University of South Florida to test a full-sized lead section to failure, while monitoring the splice-connection performance. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

O evento de previsões do comportamento carga-recalque de uma estaca executada em solo predominantemente arenoso foi apresentado no 8° Seminário de Engenharia de Fundações Especiais e Geotecnia (SEFE8). As previsões utilizaram sondagens CPT, DMT e SPT realizadas no campo experimental de Araquari, em Santa Catarina. A estaca utilizada para o evento foi do tipo escavada com polímero, diâmetro de 100cm e comprimento de 24m. Foram recebidos pelo comitê organizador 73 previsões provenientes de 20 países, com estimativas do comportamento carga-recalque da estaca, da capacidade de carga total, lateral e de ponta e a distribuição de carga ao longo do fuste até a ruptura, definida pelo recalque de 100 mm (w/D = 10%), com um resumo dos métodos e considerações. Os dados das previsões foram comparados aos resultados obtidos em campo pela prova de carga estática da estaca instrumentada. As previsões foram majoritariamente conservadoras e o ensaio mais utilizado para determinação dos parâmetros do solo foi o CPT, tanto no meio acadêmico quanto no prático Diversos métodos foram utilizados, porém mesmo previsões que utilizaram o mesmo método apresentaram variabilidades nos resultados. Baixos valores de desvio na capacidade de carga total não significaram pequenos desvios de lateral e de ponta, mas uma combinação de desvios positivos e negativos desses. A maioria das estimativas subestimou a capacidade lateral e superestimou a de ponta. O método de Verbrugge (1981) foi utilizado em duas das cinco previsões com menores desvios de capacidade total. As curvas carga-recalque e carga-profundidade foram avaliadas quanto aos desvios médios absolutos e formatos, dados pela variância. As curvas carga-recalque com médias de até 10% utilizaram Elementos Finitos e o software UniPile, e o menor valor de variância utilizou Verbrugge (1981). As curvas carga-profundidade com médias de até 10% utilizaram Verbrugge (1981), Randolph e Wroth (1978) e Gwizdala e Steczniewski (2003), e o menor valor de variância utilizou o software UniPile. / The prediction event of load-settlement behavior of a pile built in predominantly sandy soil was presented at the 8th Foundation Engineering Seminar and Special Geotechnical (SEFE8). The predictions used tests of CPT, DMT and SPT accomplished in Araquari experimental field, in Santa Catarina. A bored pile with polymer, diameter of 100cm and length of 24m was the subject of the event. The organizing committee received 73 predictions from 20 countries, with estimates of load-settlement behavior of the pile, the total, shaft and base load capacity and the load distribution along the shaft until failure, defined by settlement of 100 mm (W/D = 10%), with a brief description of methods and considerations. Data from the predictions were compared to the results obtained in the field by static load test of the instrumented pile. The predictions were mostly conservative and the test most used for soil parameters prediction was the CPT, both in academia as in practice. Several methods were used, but even predictions that used the same method showed variability in the results Low error values in the total load capacity not meant small shaft and base errors, but a combination of positive and negative errors of these. Most estimates underestimated the shaft capacity and overestimated the base. The Verbrugge (1981) method was used in two of five predictions with lower errors of total capacity. The curves were analyzed for absolute average deviation and formats, evaluated by the variance. The load-settlement distribution with average up to 10% used Finite Element and UniPile software, and the lowest value of variance used Verbrugge (1981). The load-depth distribution with average up to 10% used Verbrugge (1981), Randolph and Wroth (1978) and Gwizdala and Steczniewski (2003), and the lowest value of variance used the UniPile software.

O evento de previsões do comportamento carga-recalque de uma estaca executada em solo predominantemente arenoso foi apresentado no 8° Seminário de Engenharia de Fundações Especiais e Geotecnia (SEFE8). As previsões utilizaram sondagens CPT, DMT e SPT realizadas no campo experimental de Araquari, em Santa Catarina. A estaca utilizada para o evento foi do tipo escavada com polímero, diâmetro de 100cm e comprimento de 24m. Foram recebidos pelo comitê organizador 73 previsões provenientes de 20 países, com estimativas do comportamento carga-recalque da estaca, da capacidade de carga total, lateral e de ponta e a distribuição de carga ao longo do fuste até a ruptura, definida pelo recalque de 100 mm (w/D = 10%), com um resumo dos métodos e considerações. Os dados das previsões foram comparados aos resultados obtidos em campo pela prova de carga estática da estaca instrumentada. As previsões foram majoritariamente conservadoras e o ensaio mais utilizado para determinação dos parâmetros do solo foi o CPT, tanto no meio acadêmico quanto no prático Diversos métodos foram utilizados, porém mesmo previsões que utilizaram o mesmo método apresentaram variabilidades nos resultados. Baixos valores de desvio na capacidade de carga total não significaram pequenos desvios de lateral e de ponta, mas uma combinação de desvios positivos e negativos desses. A maioria das estimativas subestimou a capacidade lateral e superestimou a de ponta. O método de Verbrugge (1981) foi utilizado em duas das cinco previsões com menores desvios de capacidade total. As curvas carga-recalque e carga-profundidade foram avaliadas quanto aos desvios médios absolutos e formatos, dados pela variância. As curvas carga-recalque com médias de até 10% utilizaram Elementos Finitos e o software UniPile, e o menor valor de variância utilizou Verbrugge (1981). As curvas carga-profundidade com médias de até 10% utilizaram Verbrugge (1981), Randolph e Wroth (1978) e Gwizdala e Steczniewski (2003), e o menor valor de variância utilizou o software UniPile. / The prediction event of load-settlement behavior of a pile built in predominantly sandy soil was presented at the 8th Foundation Engineering Seminar and Special Geotechnical (SEFE8). The predictions used tests of CPT, DMT and SPT accomplished in Araquari experimental field, in Santa Catarina. A bored pile with polymer, diameter of 100cm and length of 24m was the subject of the event. The organizing committee received 73 predictions from 20 countries, with estimates of load-settlement behavior of the pile, the total, shaft and base load capacity and the load distribution along the shaft until failure, defined by settlement of 100 mm (W/D = 10%), with a brief description of methods and considerations. Data from the predictions were compared to the results obtained in the field by static load test of the instrumented pile. The predictions were mostly conservative and the test most used for soil parameters prediction was the CPT, both in academia as in practice. Several methods were used, but even predictions that used the same method showed variability in the results Low error values in the total load capacity not meant small shaft and base errors, but a combination of positive and negative errors of these. Most estimates underestimated the shaft capacity and overestimated the base. The Verbrugge (1981) method was used in two of five predictions with lower errors of total capacity. The curves were analyzed for absolute average deviation and formats, evaluated by the variance. The load-settlement distribution with average up to 10% used Finite Element and UniPile software, and the lowest value of variance used Verbrugge (1981). The load-depth distribution with average up to 10% used Verbrugge (1981), Randolph and Wroth (1978) and Gwizdala and Steczniewski (2003), and the lowest value of variance used the UniPile software.

Driving piles constitute a large portion of the high-capacity foundations used today. They transfer structural loads to deep bearing strata when adequate surficial soils are not available. The mechanisms required to install these piles generally consist of a hammer, hammer lead, a crane, and various support rigging. This study focused on lead sections, specifically, one which was manufactured by Berminghammer Foundation Equipment, Inc. The dimensions and strength of a lead section must be capable of supporting both the pile driving hammer and the longest anticipated pile for a given site. The strength of the section must be capable of withstanding hundreds of tons in compression and bending. If the lead is operated in a batter, (tilted forward, backward, or sideways) the weight of the hammer and pile causes much more bending than the vertical orientation. The cross-section details for these long steel sections vary from design to design but usually incorporate some form of bolt group, pins, and steel alignment dowels. This thesis focuses on the design, modeling, and testing of such a connection. The motivation of the study stems from a company-wide incentive to standardize the connections used to splice the Berminghammer C15-series lead section. In an effort to verify a proposed connection design, Berminghammer Foundation Engineering solicited the University of South Florida to test a full-sized lead section to failure, while monitoring the splice-connection performance.

The main goal of this work is to determine values of elastic constants of orthotropic, transversely isotropic and cubic materials through indentation tests on thin layers bonded to rigid substrates. Accordingly, we first use the Stroh formalism to provide an analytical solution for generalized plane strain deformations of a linear elastic anisotropic layer bonded to a rigid substrate, and indented by a rigid cylindrical indenter. The mixed boundary-value problem is challenging since the deformed indented surface of the layer contacting the rigid cylinder is unknown a priori, and is to be determined as a part of the solution of the problem. For a rigid parabolic prismatic indenter contacting either an isotropic layer or an orthotropic layer, the computed solution is found to compare well with solutions available in the literature. Parametric studies have been conducted to delimit the length and the thickness of the layer for which the derived relation between the axial load and the indentation depth is valid. We then derive an expression relating the axial load, the indentation depth, and the elastic constants of an orthotropic material. This relation is specialized to a cubic material (e.g., an FCC single crystal). By using results of three virtual (i.e., numerical) indentation tests on the same specimen oriented differently, we compute values of the elastic moduli, and show that they agree well with their expected values. The technique can be extended to other anisotropic materials. We review the literature on relations between deformations at the atomic level and stresses and strains defined at the continuum level. These are then used to compare stress and strain distributions in mechanical tests performed on atomic systems and their equivalent continuum structures. Whereas averaged stresses and strains defined in terms of the overall deformations of the atomic system match well with those derived from the continuum description of the body, their local spatial distributions differ. / Ph. D.

Most of the older reinforced concrete (RC) buildings have columns that are deficient when the current code requirements are considered. Therefore, performance of the columns determines the performance of the structure under the effects of earthquake induced lateral loads. It is recognized that no provision is proposed in TEC2007 to estimate the failure type called flexure-shear. Behavior of columns having probability of failing in flexure-shear failure mode is mostly underestimated by TEC2007 procedures. In addition, failure type classification of columns performed according to the linear and nonlinear procedures of TEC2007 needs to be examined with respect to the test results to cover all failure types including flexure-shear failure in order to lead the engineers develop economical and realistic retrofit solutions. In this study, different methods are explored to obtain reliable estimates for the performance of code deficient shear critical RC columns. Special considerations are given to Axial-Shear-Flexure interaction (ASFI) approach due to its mechanical background. After examination of different approaches, ASFI method with proposed modifications was selected as the most reliable model and lateral load-displacement analyses were performed on a database of shear critical columns. Findings were compared with the estimations of the nonlinear procedure given in Turkish Earthquake Code (TEC2007) for database columns. In addition, drift capacity equations and simplified safe drift capacity equations are proposed in light of statistical studies on the selected column specimens. In the last part of the study, performance evaluation of columns according to nonlinear procedures of FEMA 356, TEC2007, ASCE/SEI 41 update supplement, and EUROCODE 8 were conducted.