岩土力学2023，Vol.44Issue(12)：3349-3359,11.DOI:10.16285/j.rsm.2022.2005
宽广吸力范围非饱和土剪切强度试验研究及其预测
Experimental study on shear strength of unsaturated soil over a wide suction range and its prediction
摘要
Abstract
In this paper,the experimental studies on the water retention and strength properties of unsaturated weakly expansive soil in a wide suction range were carried out,and a strength model of unsaturated soil over a wide suction range was proposed.The results show that in the wide suction range,the stress-strain curve increases with the increase of suction.The strain hardening occurs in the low suction range,while the strain softening appears in the high suction range.In the low suction range,the sample presents shear deformation,while in the high suction range,the sample begins to show a shear dilation trend at the axial strain of 2％.In addition,a soil-water retention curve model was proposed to distinguish adsorbed water from capillary water,assuming that the strength increment caused by suction is mainly determined by capillary water.The degree of saturation of capillary water was used to replace the effective stress coefficient and then it was substituted into the Bishop's unsaturated soil strength formula.The proposed model was verified by test data of various soil types and compared with the models in the literature.The results show that the proposed model can well describe the strength of unsaturated soil in a wide suction range.关键词
非饱和土/剪切强度/土-水特征曲线/有效应力系数/宽广吸力范围Key words
unsaturated soil/shear strength/soil-water retention curve/effective stress coefficient/wide suction range分类
土木建筑引用本文复制引用
牛庚,朱晓凤,李俊星,吕梦缘,安荔琪,陈子晗..宽广吸力范围非饱和土剪切强度试验研究及其预测[J].岩土力学,2023,44(12):3349-3359,11.基金项目
国家自然科学基金(No.42307236,No.12172187) （No.42307236,No.12172187）
山东省自然科学基金(No.ZR2023QE001) （No.ZR2023QE001）
岩土力学与工程国家重点实验室开放基金课题(No.SKLGME021019).This work was supported by the National Natural Science Foundation of China(42307236,12172187),the Natural Science Foundation of Shandong Province(ZR2023QE001)and the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering(SKLGME021019). （No.SKLGME021019）
