Model Test of Strain Development in Cement Soil under Subway Loading
(1 Zhejiang Coal Geology Bureau of China Coal Geology Bureau, Hangzhou 310021; 2 Department of Civil Engineering, Zhejiang University City College, Hangzhou 310015)
Abstract：
Cement soil reinforcement is widely used in metro construction in soft clay zones since it can effectively improve foundation strength and reduce settlement. Due to the initial consolidation of the compound soils caused by construction disturbance, the strain development and long term deformation is affected under the function of cyclic loading. A dynamic test is conducted on cement soil by means of an indoor GDS dynamic triaxial test, and the effects of the cement mixing ratio and the initial consolidation degree on strain development are analyzed. Based on the research and experiment results, a strain development model considering the cement mixing ratio and initial consolidation degree is established. The experiment results show: 1) the lower the initial consolidation degree, the faster the strain development rate; 2) when the initial consolidation degree is low, the strain development rate of the cement soil with a low cement mixing ratio is high; and 3) the strain development of cement soil is in a non-failure form, and it is approximately a linear relationship between the dynamic strain of the cement soil and the logarithm lgN of cyclic times under different consolidations.
2018, Vol. 55 