为研究结构性花岗岩残积土的剪切屈服特性,对未扰动和重塑花岗岩残积土及作比较的掺水泥的重塑土进行了一系列不同围压下的三轴排水对比试验。结果表明,未扰动花岗岩残积土与掺水泥重塑土在剪切过程中的屈服点可以从归一化的剪切切向刚度 与轴向应变 在双对数坐标下的关系曲线中确定;固结压力 对未扰动残积土与掺水泥重塑土的屈服特性都有显著影响, 越大,等向固结作用对土体结构的破坏越严重,剪切开始阶段的初始归一化刚度会相应地越小,屈服时的轴向应变也越小;当固结压力达到足够大时,土体结构被等向固结作用完全破坏,剪切过程中没有结构性屈服现象发生, 曲线与重塑土的 曲线重合;重塑土在不同固结压力下的 曲线重叠,不随固结压力而变化,剪切过程中没有结构性屈服现象发生。
In order to investigate the shear yield characteristics of structured granite residual soil, a series of conventional triaxial drained tests are conducted on the undisturbed granite residual soil, remolded soil and cemented residual soil. From the test results, some insights can be obtained as follows. For undisturbed granite residual soil and cemented residual soil, the bond yield point during shearing could be identified on the curve of the normalized tangential stiffness versus axial strain in log-log scale. The consolidation pressure has a significant influence on the shear yield characteristics of undisturbed granite residual soil and cemented residual soil during shearing; the bonds inside structured soil tend to be damaged relatively more seriously as is higher; accordingly the initial normalized stiffness will be smaller at the beginning of the shearing process; and the axial strain at the bond yield point will also be smaller. Besides, it can be concluded that once excesses a critical value, the bonds inside soil will be damaged totally; in this case, there will be no bond yield occurring during shearing; and the curves will be coincided with the ones of remolded soil. For remolded soil, no bond yielding is observed during shearing, the curve is nearly constant with no dependence of the value of .