Evaluation of the Effects of Topography on the Horizontal and Vertical Displacement of Semi-Sine Shaped Hills against Ricker Waves

This study presents the results of a numerical study on seismic behavior of two-dimensional semi-sine shaped hills that were subjected to vertically propagating incident SV wave of the Ricker wavelet. The finite difference software is used to model and analyze the different sizes of the hills.Earthquakes are natural events that can have considerable economic and social injuries and have effects on people life and their environment. Geotechnical earthquake engineering has been noticed particularly in recent decays. Soil mass and soil structure response analysis against earthquake movements is one of the most important practical concepts in geotechnical earthquake engineering. In the case of 2D response analysis of hills, researchers studied seismic response of triangular shaped hills under vertically propagating SH waves. He used finite difference method and represented that topography has specific effect on acceleration distribution in different points of roughness. Concentration is on topographic effects, so parameters such as shape factor (the ratio of the height to half width of the hill) and the type of ground took into account in this research. The medium was assumed to have a linear elastic constitutive behavior. So we modeled semi-sine hills with different shape factors (0.1, 0.4 and 0.8) where subjected to Ricker wavelet with constant frequency on grounds with different properties that differ from each other in density and shear velocity (three types based on 2800 standard). In this research the horizontal and vertical displacements of different points on hills calculated and the results are compared with each other in different shape factors.The results indicates results in different parts that shows horizontal displacement and vertical displacement for types of field under Ricker wavelet and compared with Trinidad earthquake wave.Amplification factor calculated based on the ratio of horizontal components of motion to displacements of free-field model. The finite difference software used to run the numerical analyses was Flac 2D. The aim of this project was to investigate the response of topography effects on semi-sine shaped hills under Ricker wavelet which is the second derivative of Gauss function.The obtained results show that both horizontal and vertical displacements increased with change in shape factor. It can be seen that changing geotechnical properties of the ground type from one to three; the displacements reduced.