关键词: 深埋砂层, 物理模型试验, 旁压模量, 临塑压力, 深度效应

Abstract: Deep buried sand is a granular structure system, and accurate determination of its original mechanical properties is a difficult problem in geotechnical engineering. Pressuremeter test (PMT) is an ideal in-situ deep-seated testing method for deep buried sand, but there is a lack of quantitative evaluation criteria for the depth effect. In order to solve the problem of depth effect of PMT, a self-developed physical model testing system was applied to simulate the stress state of deep buried sand. By applying different overburden pressures to simulate the PMT at different depths, the variation rules of PMT modulus EM and PMT plastic pressure Pf as a function of overburden pressure are obtained, and a method is suggested to revise the characteristic value of the bearing capacity of foundation fak based on the PMT plastic pressure Pf. The test results show that the depth effect does exist in the PMT. With the increase of test depth, the burial overburden pressure increases, and the change of EM is not obvious. Also, Pf is linearly correlated with . This study provides reference and basis for the determination of physical and mechanical properties of deep buried sand.

Key words: deep buried sand, physical model test, PMT modulus, plastic pressure, depth effect