Determination method of drucker-prager rock and soil softening strength parameters

Abstract

The invention provides a Druker-Prager rock-soil softening intensity parameter determination method which comprises the following steps: (1) processing a test piece; (2) obtaining an axial compressive stress-axial compressive strain curve; (3) correcting the curve; (4) obtaining an average value of an elasticity modulus E; (5) obtaining each group of stress deviator second invariant and stress first invariant J21, J22 till J2N and I11, I12 till I1N; (6) obtaining the primary softening intensity parameters (alpha)0 and k0 of Druker-Prager intensity criterion of the determined rock-soil material; (7) calculating the axial plastic compressive strain increment corresponding to each group of test recording points; (8) interpolating to obtain the axial stress (alpha)i corresponding to each division point in each group of tests; (9) obtaining the intensity parameters (alpha)i and ki corresponding to each division point; (10) obtaining the functional relationship between the axial plastic compressive strain increment k and the softening intensity parameters (alpha) and k. The determination method provided by the invention meets higher design requirements for engineering structures, realizes high safety and requires low manufacturing cost.

Description

technical field [0001] The invention relates to a parameter determination method, in particular to a Drucker-Prager rock-soil softening strength parameter determination method. Background technique [0002] The plastic softening of rock and soil is the essential attribute of rock and soil failure. It is manifested as the shrinkage of the yield surface of rock and soil during the failure process. The Drucker-Prager strength criterion can reflect the failure characteristics of rock and soil materials more realistically, but the Drucker-Prager It is difficult to measure soil softening strength parameters. At present, in engineering practice, engineers and technicians can only consider rock and soil as ideal plastic materials, that is, use the Mohr-Coulomb strength criterion as the failure criterion of rock and soil materials, which cannot meet higher engineering requirements. Analysis accuracy, because higher accuracy cannot be met, therefore, in engineering practice, the use o...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the technical problem that it is difficult to determine the failure strength of rock and soil in geotechnical engineering, which leads to the hidden danger of rock and soil structure safety or the high cost of construction, the invention provides a reliable and feasible Drucker-Prager rock and soil softening strength parameter determination method