泥质粉砂岩抗剪强度试验及参数选取研究

Shear strength test and parameter selection of argillaceous siltstone

基于工程坝址区河道泥质粉砂岩工程地质条件,模拟坝基工程岩体的受力状况,对坝基泥质粉砂岩进行了岩/岩和混凝土/岩抗剪(断)强度的试验,比较了两者的差异性。比较分析认为:混凝土/岩和岩/岩抗剪(断)试验,均属于脆性破坏,最薄弱的破坏面为泥质粉砂岩的层理面。混凝土/岩抗剪(断)和岩/岩抗剪(断)试验参数相近。坝基抗剪断强度试验参数为:f′=0.86,c′=0.53 MPa;抗剪断强度试验参数标准值为:f=0.61,c=0 MPa。

Based on the engineering geological conditions of muddy siltstone in the river course in the dam site area and simulating the stress state of the rock mass in the dam foundation engineering,the shear(breaking)strength tests of muddy siltstone in the dam foundation and concrete/rock are carried out,and the differences between the two are compared.The comparative analysis shows that the shear(fracture)tests of concrete/rock and rock/rock belong to brittle failure,and the weakest failure surface is the bedding surface of argillaceous siltstone.The shear(breaking)test parameters of concrete/rock are similar to those of rock/rock.The test parameters of dam foundation shear strength are:f’=0.86,c’=0.53 MPa;the standard values of test parameters of dam foundation shear strength are:f=0.61,c=0 MPa.