取土器贯入土体引起土体扰动的理论分析

为了研究取土器贯入对土体产生的扰动影响,基于贯入问题的半无限空间特性,根据半无限空间内球孔扩张产生的变形和应变解,推导出取土器贯入土体过程中产生的应变公式.分析了取土管中心线上土体单元应变变化和其影响因素,并与Balign的结果进行了比较.结果表明,取土器贯入土体对其内部土体产生了扰动影响,其中对两端土体扰动相对较大,中间土体相对较小.取土器径厚比、长径比均对贯入过程中土体单元的应变产生影响.

Theoretical analysis of disturbance of soils caused by penetration of soil samplers

In order to determine the disturbance effects on soils of the penetration of soil samplers, an equation for the strain induced by sampling penetration was derived according to the deformation and strain of a half-space spherical cavity expansion based on the half-space characteristics of penetration problems. The strain history and factors of soil elements at the centerline of the sampling tube were analyzed, and they were compared with Balign' s results. The results show that sampling penetration has a disturbance effect on the soils in the sampler. The disturbance effect on the soils is larger at the two ends and smaller in the center. The ratios of D/t and L/D of the sampler influence the strain of the soils caused by sampling penetration.