Analysis of changing factors of retaining walls under static loads in sloped area by finite element method

In this thesis, PLAXIS 2D software, which is widely used in modelling and analysis of geotechnical problems, has been used for retaining walls, which have an important place in engineering structures. In addition, the design and cost analyses of retaining walls were carried out using Ide CAD Static and Oska software. Within the scope of the study, retaining walls were designed considering various parameters for three different sites. For Site-1 and Site-2, real field data were used, while for Site-3, wall and slope designs were analysed according to the determined scenario conditions. In the analyses, the collapse safety of the selected wall designs with respect to the slope condition, wall deformations and different soil parameters were analysed. Within the scope of the thesis, slope stability and the effect of retaining walls were examined and the displacements were evaluated, and the deformations in the soil and retaining walls were analysed by using the models obtained from the PLAXIS 2D program using the soil sections created for the sites. In addition, the deformations and stresses occurring in the soil at each stage of the construction process of the existing or designed retaining walls in the study areas were evaluated in detail. According to these analyses, it was observed that the modulus of elasticity is a critical parameter in terms of deformation control in soil-wall interaction and should be considered in the design of retaining walls. It was determined that the deformations in the retaining walls decreased with the increase in the modulus of elasticity, there was no significant effect on the total stress, and the effect on the effective stress was negligible. It was found that 3 m and 5 m retaining walls were slightly affected by the changes in cohesion and internal friction angle and these changes were negligible, while 5 m retaining walls were much less affected by the changes in cohesion and internal friction angle compared to 3 m retaining wall. It was concluded that the deformations and stresses in the 3 m and 5 m walls increased proportionally to the increase in the surcharge load, while the 5 m retaining wall exhibited a stable behaviour against the increases in the load and the changes in the deformation values were more limited. It was also found that the effective stress showed a regular increase as the load increased, while the active water pressure remained constant and was not affected by load changes. In order to design retaining walls in sloped areas in a safer and more effective way, it is concluded that parameters such as the state of groundwater level in the soil, the state of loads acting on the soil, modulus of elasticity, cohesion and internal friction angle play a critical role in the performance of retaining walls. Keywords: Displacement, Plaxis 2d, Retaining walls, Static load