A DAMAGE COUPLED VISCO-ELASTIC COMPONENT MODEL FOR BRITTLE ROCKS

摘要

To explain the time-dependent and damage behavior of brittle rocks, a generalized damage coupled visco-elastic(DVE) component model is presented. A simple DVE component model is discussed firstly; it consists of two units in parallel, i. e. a sub-model named brittle spring connected by a linear spring and a brittle cementation bar in series, and a Maxwell model, which are used to represent elasto-brittle and visco-elastic characteristics of brittle rocks, respectively.The new model is an extension of the Maxwell model and the three element component model similar to Merchant mode, and the initial, deceleration, acceleration and equal velocity creep can be depicted by it. Stress drop and strain softening stress-strain behavior can also be showed in the constant-rate-of-strain loading for mesoscopic heterogeneous brittle rocks. Based on the simple model, a generalized DVE component model composed of a Maxwell model and multi brittle springs is put forward. The progressing damage characteristics can be described by it in the constant-rate-of-strain loading for brittle rocks.