摘要
影响环剪仪试验精度的因素有多种,而试验方法是其中一种。Bromhead环剪仪采用顶部荷载板加荷的方式,且荷载板与试样盒内壁预留缝隙。试验中观察到,随着剪切位移的增大,土样会被挤出,并残留在荷载板与试样盒壁之间。挤出的土体会增加荷载板与试样盒的摩擦,夸大作用在试样上的剪应力。分析了环剪仪的三种试验方法。与多级剪相比,单级剪的试验方法能够避免荷载板较大的旋转位移,减弱挤土现象,减小试验误差。砂土试样的环剪试验表明,单级剪方法测得的残余强度比多级剪方法小。
Many factors influence the accuracy of the ring shear tests, and the test procedure is one of them. The Bromhead ring shear apparatus employs the top load plate for shear, and the gap between the load plate and the specimen container is set. It is observed in the experiment that the soil specimen is extruded with the increase of shearing displacement. The magnitude of the wall friction developed during shear is directly linked to the intrusion of the top plate into the specimen container. The actual shearing stress on the specimen is less than the measured stress. Three test procedures are discussed. Compared with the multistage ring shear test procedure, the single-stage test procedure can avoid more rotational displacement of the load plate, minish extrusion effect and decrease test error. The ring shear tests on sand sepecimens show that the residual strength of sand of the single-stage shear test procedure is less than that of multistage one.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2013年第S2期197-201,共5页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(41102203)
华北水利水电学院高层次人才引进项目(001257)
关键词
环剪试验
残余强度
单级剪
多级剪
ring shear test
residual strength
single-stage shear
multistage shear
