非饱和心墙料的固结不排水试验特性

Characteristics of unsaturated core soil in earth-rock dam under consolidated undrained test

土石坝心墙在施工期间处于非饱和状态,且坝体是分级填筑的。应力变形计算时将载荷分成若干级增量,每一级增量假设瞬间完成,等固结一段时间后再施加下一级载荷。由于施加荷载的瞬间来不及排水,因此,总应力法计算参数可以由固结不排水、不排气试验取得。通过三轴试验,揭示了非饱和心墙料的固结、应力-应变及侧向变形特征,探讨了固结过程中体积应变随时间的变化规律,建立了切线泊松比与围压的双曲线关系模型。

An earth-rock dam is constructed with many layers and its core wall is unsaturated in construction period. The whole load of dam is divided into several increments for the calculation of stress and deformation. It is supposed that the increment is added instantaneously and then the dam is consolidated some times under the increment. Thus, the parameters for calculation can be taken from the consolidated undrained triaxial test. The characteristics of consolidation and stress-strain relationship and lateral deformation of test are presented. The law about the volume strain with time in consolidation process is discussed. The hyperbolic model for tangent Poisson ratio is also presented.