Determination method of stress intensity factor for anisotropic materials with multiple round holes and multiple cracks

Abstract

The invention discloses a method for measuring the stress intensity factor of an anisotropic material with many circular holes and multiple cracks. The steps are as follows: taking the material to be tested as a prototype, constructing a plane unit model containing multiple circular holes and multiple cracks, and defining boundary conditions ; Construct a plane element model containing a single circular hole, and solve the basic stress solution of the model subjected to the concentrated force on the surface of the orifice according to the complex variable function Cauchy integral theory; construct a plane element model containing a single crack, according to the complex variable function Cauchy integral theory Solve the basic stress solution of the model subjected to the concentrated force on the surface of the crack; according to the obtained basic stress solution and stress boundary conditions, obtain the integral equation about the interaction surface stress of each circular hole and each crack; discretize the obtained integral equation It is a linear algebraic equation; the formula for calculating the stress intensity factor of the plane element model containing a single crack is derived, and the stress intensity factor of the plane element model under the interaction of multiple circular holes and multiple cracks is calculated in combination with the solved crack surface interaction surface stress.

Description

technical field

[0001] The invention belongs to the technical field of fracture mechanics, in particular to a method for measuring the stress intensity factor of anisotropic materials with many round holes and many cracks. Background technique

[0002] In rock mass engineering such as slopes, water conservancy projects, tunnels, and mineral mining, natural rocks often show obvious anisotropy characteristics, and often contain defects such as cracks inside, and the existence of cracks causes cracks in the rock mass structure. The stress is more concentrated, which reduces the mechanical properties of the rock mass structure and greatly increases the engineering risk factor. Since arranging suitable round holes near the crack can effectively reduce the stress intensity factor of the crack tip, the drilling arrest method is a common and effective method to improve the engineering strength of rock mass. In addition, in the exploitation of shale gas, the hydraulic fracturing tec...

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