Observations from Centrifuge Modeling for Cement-treated Clay Slopes |
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학술지명 대한토목학회
저자 박동순
발표일 2012-10-25
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A total of 12 static and dynamic centrifuge tests were performed on cement-treated clay slopes and lightly overconsolidated clay slope. Seven tests were composed of high plasticity clay (San Francisco Bay Mud with cement mix ratio of 3 to 5%). The others were composed of low plasticity silty clay (Yolo Loam with cement ratio of 2 to 3%). It is observed that limit equilibrium analysis using peak strength as a function of depth works fine to evaluate the stability of cement treated clay slopes. There are a couple exceptions in that limit equilibrium analysis does not account for the effect of cement mixing ratio, which can be related to the degree of cementation. The failure mode of slopes made of cement-treated SFBM was typically deep and long toe circle slip surface whereas cement-treated Yolo Loam (YL) exhibited shallower slip surface within the slope because YL models had steeper gradient of shear strength with depth (due to a significantly greater buoyant unit weight). Due to the effects of high static shear stress and plasticity, and possibly due to time lag associated with measurement of pore pressures in clay and possibly that the sensors were not located in the regions of maximum pore pressure, the measured pore pressure ratios within clay were somewhat less than expected. |