Development and application of self-boring in-situ shear pressuremeter

It is of great importance to precisely appraise the mechanic characteristics and provide credible design parameters of soils for the design of foundation engineering. At present, the strength and deformation parameters are tested by different test methods whose precisions differ from each other, and the soils are disturbed inevitably to some degree, so are the stresses in the soils. The self-boring in-situ shear pressuremeter test, on the basis of the conventional pressuremeter test and the indoor direct shear test, adopts the self-boring technique, sends the probe to the preplanned depth of soils, tries its best to reduce the disturbance and holds the initial stresses in the earth. The unique structure and loading method make it possible to directly attain many mechanic parameters, such as the strength and deformation parameters, earth pressure at rest, coefficients of subgrade shear reaction, pile friction and so on. And the self-boring in-situ shear pressuremeter test is a testing technique in the drilling boreholes, so it can obtain the mechanic parameters of different depths in the soils.