This thesis addresses the results of an experimental and analytical investigation aimed at examining the static load-displacement response of braced plane frame structures composed of fiber reinforced polymeric (FRP) composite material structural members manufactured by the pultrusion process. In the experimental part of this investigation, eighteen full-scale lateral loading tests for FRP composite frames with different brace configurations and beam column connection types were performed. The load-displacement responses of such frames were measured and are reported herein. In the analytical part of this investigation, a frame analysis method that accounts for the anisotropic nature of FRP composite material structural members was investigated. The results from the experimental work are compared with the results from the analytical procedures. The effects of various structural parameters of the frame such as (1) effective mechanical material properties of members, (2) beam-column connection types, and (3) the influence of diagonal structural members on the lateral load-displacement response of the braced plane frames are also investigated. The numerical load-displacement results from the proposed FRP composite frames analysis procedure provided good agreement with the results from the full-scale laboratory tests.

A structure subjected to extreme load due to explosion or human error may lead to progressive collapse. One of the direct methods specified by design guidelines for assessing progressive collapse is the Alternate Load Path method which involves removal of a structural member and analysing the structure to assess its potential of bridging over the removed member without collapse. The use of this method in assessing progressive collapse therefore requires that the vertical load resistance function of the bridging beam assembly, which for a typical laterally restrained reinforced concrete (RC) beams include flexural, compressive arching action and catenary action, be accurately predicted. In this thesis, a comprehensive study on a reliable prediction of the resistance function for the bridging RC beam assemblies is conducted, with a particular focus on a) the arching effect, and b) the catenary effect considering strength degradations. A critical analysis of the effect of axial restraint, flexural reinforcement ratio and span-depth ratio on compressive arching action are evaluated in quantitative terms. A more detailed theoretical model for the prediction of load-displacement behaviour of RC beam assemblies within the compressive arching response regime is presented. The proposed model takes into account the compounding effect of bending and arching from both the deformation and force points of view. Comparisons with experimental results show good agreement. Following the compressive arching action, catenary action can develop at a much larger displacement regime, and this action could help address collapse. A complete resistance function should adequately account for the catenary action as well as the arching effect. To this end, a generic catenary model which takes into consideration the strength degradation due to local failure events (e.g. rupture of bottom rebar or fracture of a steel weld) and the eventual failure limit is proposed. The application of the model in predicting the resistance function in beam assemblies with strength degradations is discussed. The validity of the proposed model is checked against predictions from finite element model and experimental tests. The result indicate that strength degradation can be accurately captured by the model. Finally, the above developed model framework is employed in investigative studies to demonstrate the application of the resistance functions in a dynamic analysis procedure, as well as the significance of the compressive arching effect and the catenary action in the progressive collapse resistance in different designs. The importance of an accurate prediction of the arching effect and the limiting displacement for the catenary action is highlighted.

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The master thesis consists of a theoretical part and a practical part. In the theoretical part jet-grouting technology is described briefly. Mechanical properties of jet-grouted piles were characterized. Various estimation methods of ultimate pile bearing capacity are described in this thesis – analytical calculation of ultimate bearing capacity for bored piles and estimation of ultimate pile bearing capacity by analysis of load-displacement curve defined by CHIN (1970; 1972). Load transfer method for piles and hyperbolic load-transfer curve are introduced. As a part of the load-trasfer method analysis, a method of estimating ultimate pile shaft friction called beta method is defined. In the practical part were evaluated several static load tests of jet-grouted piles and were constructed their load-displacemnt curves. Then reverse analysis of the results from static load tests was performed using load-transfer method. Then ultimate pile bearing capacity was estimated using analytical calculation of pile bearing capacity for bored piles and using analysis of load-displacement curve with method by CHIN (1970; 1972). By evaluation of load transfer method and beta method ultimate shaft resistence for each pile was estimated. Results and load-displacement curves were compared.

Diploma thesis is focused on the description of the parameters of nonlinear material models of concrete, which are implemented in a computational system LS-DYNA, interacting with performance of nonlinear test calculations in system LS-DYNA on selected problems, which are formed mainly by simulations of tests of mechanical and physical properties of concrete in uniaxial compressive and tensile on cylinders with applying different boundary conditions and by simulation of bending slab, with subsequent comparison of some results of test calculations with results of the experiment. The thesis includes creation of appropriate geometric models of selected problems, meshing of these geometric models, description of parameters and application of nonlinear material models of concrete on selected problems, application of loads and boundary conditions on selected problems and performance of nonlinear calculations in a computational system LS-DYNA. Evaluation of results is made on the basis of stress-strain diagrams and load-displacement diagrams based on nonlinear calculations taking into account strain rate effects and on the basis of hysteresis curves based on nonlinear calculations in case of application of cyclic loading on selected problems. Verification of nonlinear material models of concrete is made on the basis of comparison of some results of test calculations with results obtained from the experiment.