结构性对黄土压缩回弹性能影响的试验研究

Experimental research on the influence of the soil structure on the resilience of loess

根据黄土的大孔隙、高强度及欠压密等特性,对不同含水量的原状土与重塑土进行了一系列侧限压缩试验,包括压缩试验、压缩再回弹试验和压缩回弹再压缩试验,并对天然含水量下原状土进行4种不同荷载下的回弹再压缩试验.在试验的基础上详细分析了结构性对黄土的压缩和回弹性能的影响,尤其是对原状土在结构屈服前后的力学性能变化的影响,得出黄土的结构性对其压缩回弹性能的影响显著,特别是在结构屈服压力前后,原状土的回弹能力差别较大.研究成果为提出一种结构性黄土先期固结压力的推求方法奠定了基础.

According to the loess’s characteristics of large pores, high strength and less compaction etc. , compression-rebound test,undisturbed soil compression-rebound and compression test under four kinds of load separately for undisturbed soil and remoldedsoil with different moisture contents on the basis of unconfined compression test were carried out in this paper. The effect of soilstructure on the compression and resilience properties of the loess especially the change of the mechanical property before and afterstructural yield was analyzed according to the test results. The conclusion that the structural property of loess influence the compressiveand resilient properties significantly can be drawn. Especially, the undisturbed soil resilience presented large difference beforeand after the structural yield pressure. The study provides a basis for the method of pre-consolidation pressure of intact loess.