Influence of the compaction procedure on mechanical behaviors and pore characteristics of silts
REN Kebin1，2，WANG Bo1，LI Xinming3，YIN Song3
(1. School of Water Conservancy and Environment，Zhengzhou University，Zhengzhou，Henan 450001，China；2. Henan Provincial Architectural Heritage Protection and Research Institute，Zhengzhou，Henan 450002，China；3. School of Civil Engineering and Architecture，Zhongyuan University of Technology，Zhengzhou，Henan 450007，China)
Abstract：Taking Zhengzhou silt as the research object，the samples were prepared by static and dynamic compaction methods，and a series of triaxial shear tests and mercury injection tests were carried out to study the influence of different sample preparation conditions on mechanical behaviours and pore structure distribution of silt. The results show that the influence of the sample preparation method and the water content on the stress and strain relationship depends on the confining pressure. The stress and strain relationship of dynamic compaction samples transfers from the strain softening type with lower confining pressure and lower water content to the strain hardening type with larger confining pressure and larger water content，while the relationship of static compaction samples is always the strain hardening type. The shear strength and the cohesion of the samples obtained by the two sample preparation methods reach the maximums at the optimal moisture content. The shear strength and the cohesion of the dynamic compacted samples are higher than those of the static compacted samples for the case of the same water content，while the sample preparation method has no obvious influence on the residual cohesion of silty soil. Mercury injection test results indicate that，compared with the dynamic compaction samples，the pore diameter distribution curve of the static compaction samples shifts to the right as a whole，the peak pore diameter and distribution density increase and the larger pore content is more. The research results can explain the evolution law of the mechanical property of the static and dynamic compaction samples to some extent.
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2019, Vol. 38 
