Wind farm construction is increasing progressively, to cope-up with the current global energy scenario. The advantage of clean energy and sustainability helps wind turbine construction to flourish rapidly. Location of wind turbines is independent of foundation soil condition but depends on the wind speeds and socio-environment issues. Hence, a construction sites may not be favorable in terms of geotechnical demands. The taller wind towers facilitate the generation of high energy production, which will increase loads on the foundation, and eventually increase the dimension of the foundation. Hence, the choice of a suitable foundation system is necessary for geotechnical engineer to design tall wind towers. This study aims to analyze different foundation types e.g., raft/mat foundation, pile group foundation, and piled raft/mat foundation using analytical calculation verified with numerical models using PLAXIS 3D software. The foundation for steel wind turbine towers 100 m high was designed for different types of soils e.g., soft clayey soil, medium-stiff clayey soil, stiff clayey soil, and sandy soil. The design wind speed was taken from the ASCE 7-10 (2010) standard for Occupancy Category III and IV Buildings and Other Structures, as the Illinois region falls in that category. The parametric study was performed by varying the diameter of raft/mat, wind speed, number of piles, and soil types to evaluate the settlement in any type of foundation with load sharing proportion in piled raft/mat foundation. First, the raft/mat foundation design was carried out manually by changing the diameter of 15 m, 20 m, 25 m, 30 m, and 35 m, and changing load by considering different wind speed. Then the foundation was modeled using PLAXIS 3D software with a raft/mat diameter of 25 m, 30 m, and 35 m only, by considering the eccentricity and factor of safety criteria. With the increase in wind speed, the differential settlement on the raft/mat foundation was found to be increased. However, the increase in diameter of raft/mat caused the reduction in differential settlement. Soft clayey soil was found to be more sensitive than other soils used in the present study. For the same diameter of raft/mat, applied the same wind load, the differential settlement of foundation in soft clayey soil was found to be 6-10 times higher than the sandy soil.The position of piles was fixed based on the spacing criteria in the pile group foundation. The number of piles used in this study were 23, 32, and 46. Settlement was found to be varied with the number of piles in all soils used in this study. The lateral deflection for soft clayey soil decreased to half, when number of piles increased from 23 to 46. The differential settlement was found to be increased with the increase in wind speed in pile group foundation. Raft/mat foundation settlement was found to be 4 to 6 times higher than the settlement in pile group foundation in any soils, used in this study, for a given wind speed.The result of piled raft/mat foundation showed that the majority of the total load is shared by the piles (i.e., 60% to 94%) and remaining load is shared by the raft/mat (i.e., 6% to 40%), based on the stiffness of raft/mat and piles as well as pile-soil-pile interaction. The increase in wind speed in the wind turbines increased the differential settlement of piled raft/mat foundation in all soils. Similarly, the lateral deflection also increased with the increase in wind speed in pile raft/mat foundation in all soils. The PLAXIS 3D analysis revealed that the differential settlement in soft clayey soil was 1.5 to 2.0 times higher than the settlement in sandy soil.The validation of numerical modeling was carried out by the raft/mat foundation using Boussinesq’s theory and calculating settlement for single pile and group pile foundation. The current study showed that the soft clayey soil and medium-stiff clayey soil favor deep foundation, like pile group and piled raft/mat rather than shallow foundation, like raft/mat foundation. The results obtained from both analytical calculation and numerical modeling was found to be approximately matching. This study will help local construction company and geotechnical engineer to guide a proper foundation design of tall onshore wind turbine.

[pt] Este trabalho analisa excitações verticais dinâmicas de máquinas para fundações com embutimento. Combinações de fundações superficiais e profundas, para simulação de bloco de fundações, são analisadas com uso de diferentes metodologias. Analisam-se soluções de Novak e Beredugo em combinação com Novak e El-Sharnouby, com uso de porcentagens de recalque adicional retiradas do trabalho de Poulos e Davis. Também são analisadas soluções simplificadas de fundações superficiais com embutimento de Wolf em combinação com fundações profundas de Novak e El-sharnouby, com uso de porcentagens de recalque adicional dinâmicas,obtidas com elementos finitos neste trabalho. São comparados os valores de deslocamentos de regime permanente com os obtidos por elementos finitos tridimensionais com uso do programa Plaxis 3D, comprovando a eficácia dos valores de taxa de recalque adimensional dinâmico e uso de modelo simplificado de fundações superficiais de Wolf. / [en] This paper analyzes dynamic vertical loadings due to machine foundations on embedded foundations. Combinations of shallow and deep foundations, to pile raft foundations, are analyzed using diferent approaches. First, solutions of Novak and Beredugo combined with Novak and El- Sharnouby, using additional settlement ratios from Poulos and Davis. Then it is compared to simplified embedded shallow foundations solutions by Wolf combined with Novak and El-Sharnouby, using dynamic additional settlement ratio obtained by finite elements on this paper. Settlements obtained on the steady state regime are compared to the values obtained by tridimensional finite elements using the program Plaxis 3D, proving the efficiency of dynamic additional settlement ratio and the simplified model of shallow foundations by Wolf.

The subject topic of this thesis is to establish a suitable technique of tunnel construction using New Austrian Tunnelling Method with the help of mathematical modeling. Based on the mathematical modelling output the dimensioning primary moulding model was executed.

The subject of the diploma thesis is the stress analysis of the circular and elliptical shaft from material jet grouting. A new advanced constitutive Shotcrete model will be applied on the material jet grouting. In the thesis, the shaft tensile strength factor and the size of the ground pressures will be primarily examined. The practical part of the diploma thesis is completed by the comparison of the analytical and numerical calculation of the normal force of the circular and elliptical shafts.

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.

This work is focused on the application of advanced elasto-plastic material model intended for shotcrete. Spatial mathematical models of two laboratory tests are created, where this model is used. The first test is a three-point bending concrete specimen. Next, the behavior of the material is analyzed, in which input parameters are entered. Consequently, two reverse analyzes of the available data are analyzed where a match between prediction and measurement can be obtained. The second test is a modified tensile test, where is describe the material behavior in changing of input parameters. Subsequently, reverse data analysis is created, where an acceptable match between prediction and measurement is possible. In every study, the stress waveform in the fracture process zone is analyzed to more detail.

The subject of the presented thesis is a foundation pit dewatering numerical analysis. The study is introduced with practical examples and the summary of the necessary theory. Individual subtasks are modeled as two or three-dimensional problem on a chosen foundation pit example. A comparison with analytical methods and theoretical knowledge about the problem is made. The studies focus on specifying the pumped water quantity, the shape of the depression curve, determining the size of the numerical model and the influence of the finite element network density. The steady-state flow cases, water table aquifer, a well system, sheet pile wall cutoff effect, surface drained pit and partial penetration cases are analyzed. The work proposes a method of modeling a well by FEM. The main output is a 3D analysis of a submerged excavation dewatered with a partially penetrated well system.

The diploma thesis focuses on analysing the current Railway Infrastructure Administration methodology for designing the sleeper substructure concerning the construction's deformation resistance, its comparison with the multi-layered method, which is used in the road engineering and finite element method. It deals with various methodologies of determining the deformation resistance of the track substructure.