CALCULATION OF THE STRESS CONCENTRATION IN A ROCK MASS NEAR A MINED-OUT SPACE BASED ON A NONLOCAL ELASTIC-PLASTIC MODEL

Abstract

The problem of stress redistribution in a rock mass in the cross of two parallel workings is considered within the framework of a non-local gradient model. The constitutive equations describe plastic intergranular shifts and local heterogeneity. Two independent displacement fields are used to describe the kinematics in the plane case. As a result, the model contains a structural parameter that includes the length dimension and describes local bends of elementary volumes. Examples of numerical simulations of the development of plastic deformation zones nearby the opening contour of the rock mass are given, and areas of increased stress concentration are determined. It is shown that taking into account local bends, on the one hand, leads to a decrease in plastic shifts nearby the opening contour, and on the other hand, to a deeper penetration of areas of high stress concentration into the rock mass.