Seismic analysis of stone column reinforced slopes with finite element method

Slope stability is the leading one among the most important issues of geotechnical engineering. Recently, great slope failures (landslides), which result from earthquakes, have caused many losses of life and property. As a result, the behavior of slopes under the effect of earthquakes has been a significant issue. Taking stand from this fact, many methods have been developed in order to improve sliding resistance of ground and/or reduce the factors triggering the movements in slope under the effect of both static and dynamic load such as an earthquake with the purpose of preventing any loss of life and property caused by slope failure. One of these methods is the stone column technique which is used for the resolution of many problems such as improving bearing capacity, preventing liquefaction and ensuring slope stability. In this study, Plaxis 2D finite element program was used to analyze the stone column-free slopes modeled at different c/(.H) rate and in different slope angles (15° 20° 25°) and stone column slopes modeled at different s/D ranges (Distance between stone columns/diameter of the stone column) (2, 2.5, 3), different friction angle (: 35, 40, 45) of the material stone column safety factors were detected. Afterwards, safety factor and horizontal displacement values of the same slope models under the effect of earthquake force were detected. At the end of the research, safety factor values of slopes strengthened with stone column increased 1.001-1.416 times compared to stone column-free slopes without the effect of earthquake; while these values increased 1.001-1.293 times under the effect of earthquake force. In addition, horizontal displacement values decreased 1.111-1.737 times in slopes strengthened with stone columns compared to stone column-free slopes under the effect of earthquake force. KeyWords: Slope stability, Seismic slope stability, Earthquake force, Stone columns, Finite element program.