含水率对残积土与土工织物界面剪切特性的影响  

Effect of Moisture Content on the Shear Characteristics of the Interface Between Residual Soil and Geotextile

作　　者：冯忞 宋文捷 FENG Min;SONG Wenjie(Shanghai Pudong Architectural Design and Research Institute Co.,Ltd.,Shanghai 201204,China;School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海浦东建筑设计研究院有限公司,上海201204 [2]上海大学力学与工程科学学院,上海200444

出　　处：《华南地震》2024年第1期157-164,共8页South China Journal of Seismology

基　　金：国家自然科学基金资助项目(51678352)。

摘　　要：为探究不同影响因素下残积土与土工织物界面的剪切特性,采用气动直剪仪对土工织物加筋残积土试样进行直剪试验。考虑含水率、剪切速率、竖向应力等因素,分析不同剪切速率和竖向应力下含水率对残积土与土工织物界面剪切特性的影响。试验结果表明:在同一含水率情况下,筋土界面的抗剪强度与竖向应力成正比,在含水率为17%时,竖向应力50 kPa的抗剪强度从53 kPa分别增加到84 kPa(100 kPa)、151 kPa(200 kPa);随着含水率的增加,界面似黏聚力显著降低,筋土界面抗剪强度减小,而界面摩擦角无明显变化。剪切速度主要影响筋土界面摩擦角,筋土界面抗剪强度随着剪切速率的增大而增大;且在高剪切速率、低含水率情况下,筋土界面的剪缩现象在达到一定剪切位移后有所缓解,最后趋于平稳。In order to investigate the shear characteristics of the interface between residual soil and geotextile under different influence factors,the direct shear tests were carried out on the residual soil samples reinforced with geotextile by using pneumatic direct shear apparatus.Considering moisture content,shear rate,vertical stress and other factors,the effect of moisture content on the shear characteristics of the interface between residual soil and geotextile under different shear rates and vertical stresses is analyzed.The test results show that the shear strength of the reinforced soil interface is proportional to the vertical stress under the same moisture content,and when the moisture content is 17%,the shear strength of the vertical stress of 50 kPa increases from 53 kPa to 84 kPa(100 kPa)and 151 kPa(200 kPa),respectively.With the increase of moisture content,the apparent cohesion and shear strength of the reinforced soil interface decrease significantly,but the friction angle of the soil interface has no obvious change.The shear rate mainly affects the friction angle of the reinforced soil interface,and the shear strength of the reinforced soil interface increases with the increase of shear rate.In the case of high shear rate and low moisture content,the shear shrinkage of the interface is relieved after reaching a certain shear displacement,and finally tends to be stable.

关 键 词：加筋土 筋土界面 直剪试验 抗剪强度 含水率 

分 类 号：TU442[建筑科学—岩土工程]