A general equivalent continuum model and elastic wave velocity analysis of jointed rock masses

• Published in: International journal of rock mechanics and mining sciences (Oxford, England : 1997) Vol. 170; p. 105500
• Main Authors: Hua, Dongjie, Jiang, Qinghui
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2023
• Subjects: Compliance tensor; Continuum model; Elastic wave velocities; Jointed rock mass; Compliance tensor; Continuum model; Elastic wave velocities; Jointed rock mass
• ISSN: 1365-1609; 1873-4545
• DOI: 10.1016/j.ijrmms.2023.105500

The presence of joints dramatically affects the mechanical behavior of rock mass. For highly fractured jointed rock mass, it is more convenient to treat the jointed rock mass as equivalent continuum material. Consequently, several researchers have proposed continuum models to describe the mechanical behavior of jointed rock mass. These models are reviewed and their limitations are discussed. From the perspective of energy conservation, a general continuum model for jointed rock mass is proposed in this study, which incorporates a fourth-rank compliance tensor for joints. The stiffness, areas and orientations of joints are included in the compliance tensor. The proposed compliance tensor is in a general form, which is applicable for joints of arbitrary shape, such as penny-shaped joints and multi-sets of persistent/non-persistent joints etc. The directional modulus and Poisson's ratio of jointed rock mass are deduced from the proposed model. Besides, the elastic wave velocities of jointed rock mass are analyzed from the proposed model according to Christoffel equation. It is found that the square of longitudinal wave velocity is approximately proportional to directional modulus of jointed rock mass. Effectiveness of the proposed model is verified by comparisons with both in situ tests and numerical simulations. •A general equivalent continuum model for jointed rock mass is proposed.•The directional modulus and Poisson's ratio of jointed rock mass are deduced from the proposed model.•It is found that the square of longitudinal wave velocity is approximately proportional to directional modulus of jointed rock mass.