Abstract：Based on the failure mechanism of cement-soil pile group under seismic loading，the dynamic cyclic shear tests of cement-soil were carried out by using GDS dynamic simple shear apparatus to study the effect of cement ratio and cyclic stress ratio on dynamic deformation，dynamic strength and degradation characteristics. The results indicated that the dynamic shear strain developed more slowly and the dynamic strength was gradually increased with the cement ratio increasing. However，the results of the increase of cyclic stress ratio were opposite. It was shown that the critical cyclic stress ratios were 0.267，0.286 and 0.327 for the cement-soil with cement ratio of 5%，10% and 15%，respectively. Using the failure criteria of turning strain and the method of normalization， the model between cyclic stress ratio and failure number was established. The degradation index of cement-soil reduced with the increase of cyclic stress ratio and cyclic number under cyclic loading，and the Semi-logarithmic model could more accurately describe the degradation characteristics of cement-soil.
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2016, Vol. 35 
