冲击加载下非饱和冻土的抗压强度及能量分析

Compressive Strength and Energy Analysis of Unsaturated Frozen Soil Under Impact Loading

为了探究冲击加载下初始含水率和加载应变率对非饱和冻土抗压强度的影响,利用分离式霍普金森压杆(SHPB)对不同初始含水率下的非饱和冻土进行不同加载应变率下的冲击压缩试验,发现非饱和冻土的抗压强度随加载应变率和初始含水率的增加而增大。为了分析非饱和冻土在冲击加载下的抗压强度和破坏情况,从能量的角度分析非饱和冻土在冲击过程中吸收能与加载应变率和含水率之间的关系。结果表明:能量吸收的多少可以直观地反映非饱和冻土的抗压强度,同时可以反映出加载应变率和初始含水率对非饱和冻土抗压强度影响的主次。通过分析非饱和冻土在冲击加载下的能量-时程关系,可以直观地了解非饱和冻土在不同加载时刻的破坏情况。

In order to explore the influence of initial moisture content and loading strain rate on the compressive strength of unsaturated frozen soil under impact loading, the split Hopkinson compression bar(SHPB) is used to carry out impact compression tests on unsaturated frozen soil with different initial moisture content and loading strain rate. It can be found that the compressive strength of unsaturated frozen soil increases with the increase of loading strain rate and initial moisture content. In order to analyze the compressive strength and failure of unsaturated frozen soil under impact loading, the relationship between the absorbed energy of unsaturated frozen soil and the loading strain rate and moisture content is analyzed from the energy point of view.The results show that the compressive strength of unsaturated frozen soil can be directly reflected according to the amount of energy absorption, and the influence of loading strain rate and initial moisture content on the compressive strength of unsaturated frozen soil can also be reflected. By analyzing the energy-time relationship of unsaturated frozen soil under impact loading, we can intuitively understand the damage of unsaturated frozen soil at different loading times.