Design Of A New Device For Measuring In-situ Shear Strength Of Soils And Study Of Its Principle

In-situ-test of soil mechanical parameters is an important method in soil and rock engineering prospect. It can provide a reliable proof in engineering design and construction. In the process of underground space development and use, sometimes since the constraint of ground condition, underground test take place of ground in-situ-test, such as test grouting consolidation effect of tunnel wall rock and soil. Therefore, this article study the feasibility of a new underground test soil mechanics parameters device and proposed a related test method.This paper contains main research works and results below:(1) The paper carry out a lot of literature research work before beginning, which gives a brief introduction of the current situations of the research on the in-situ-test at home and abroad (for instance, Static cone penetration test. Flat shovel to the side of the bulge test and so on.), and summarize the advantages and disadvantages briefly.(2) Based on theory of elasticity and soil plastic limit equilibrium theory, and combined the demand of underground in-situ-test, based on Vesic’s cavity expansion theory setting up the formula of the internal friction and cohesive force between the pressure in the hole and the soil, these formulas can used as the principle of soil shear strength parameters in-situ-test.(3)Using finite element software to simulate the soil round hole expansion, and compare theoretical results with simulation results, then analysis results show that the feasibility of soil shear strength parameters in-situ-test(4) Launched a new concept design of soil shear strength parameters in-situ-test device based on the former proposed principle and methods about soil shear strength parameters in-situ-test.