信阳师范大学学报（自然科学版）2026，Vol.39Issue(1)：1-9,9.DOI:10.3969/j.issn.2097-583X.2026.01.001
基于强度测试结果的压实膨胀土有效应力参数
Effective stress parameters of compacted expansive soil based on strength test results
摘要
Abstract
The effective stress parameter χ quantifies the efficiency with which suction was converted into effective stress;clarifying its variation pattern and reliable test methods remains one of the core challenges in unsaturated soil mechanics.Because χ was extremely difficult to measure directly,experimental data were scarce.Using a complete set of measured shear strength and suction data obtained for a compacted yellow-brown expansive soil from Jingmen,the dependencies were established among χ,net stress,suction,void ratio e,and gravimetric water content w.The results showed that:① Moisture effect:At a given density,χ increased with w,indicating that the efficiency of converting suction into effective stress rises with increasing water content.② Density effect:At a fixed moisture level,χ rised markedly as e decreased,demonstrating strong density dependence-higher density significantly enhances the suction-to-stress conversion efficiency.③ Stress effect:Under constant e and w,χ increased with vertical net stress,implying that the external stress state also influences χ;the mechanism was analogous to the density effect because greater vertical stress induces specimen compaction.④ Peak("mountain")effect:Unsaturated shear strength exhibited a"peak phenomenon"because χ increased whereas matric suction decreased with rising moisture.At low moisture,χ was small and suction was large;at high moisture,χ was large and suction was small.Consequently,suction-induced strength reached a maximum over the full transition from saturation to air-drying,producing a corresponding peak in unsaturated shear strength.⑤ Research outlook:Because χ was closely linked to density,moisture and stress state,developing more rational quantitative descriptions of these interrelations warranted further investigation.关键词
有效应力参数/非饱和土/吸力/非饱和抗剪强度/山峰效应Key words
effective stress parameter/unsaturated soils/matric suction/unsaturated shear strength/peak effect分类
建筑与水利引用本文复制引用
周葆春,霍冠旭,马全国..基于强度测试结果的压实膨胀土有效应力参数[J].信阳师范大学学报（自然科学版）,2026,39(1):1-9,9.基金项目
国家自然科学基金项目(52578435 （）
11772290 （）
51009118) （）
河南省自然科学基金项目(252300421342) （252300421342）
