关键词: 地质力学模型试验, 流-固耦合, 相似材料, 胶结剂, 岩石力学

Abstract: To assess the variation of stress and deformation of surrounding rock during the process of tunnel water inrush, this paper aims at developing new types of similar material of fault and surrounding rock. The similar materials are further used in the solid-fluid coupling model test according to the similarity principle of geomechanical model tests. The developed fault similar material consists of sand, talc powder, gypsum, bentonite and paraffin liquid. The similar material of surrounding rock is composed of sand, barite powder, talc powder, white cement and latex. In these two materials, sand and talc powder are used as the coarse aggregate and the fine aggregate, respectively. Bentonite is used as cementing agents and paraffin liquid is used as a regulator in the fault similar material. The latex is used as bonder in the surrounding rock similar materials. A large amount of experimental tests are conducted to examine the deformation and failure behaviors of similar materials and prototype rocks. By adjusting the ratios of various ingredients of similar materials, the effects of sand, talc powder, gypsum, bentonite, paraffin liquid, barite powder, white cement and latex, on the uniaxial compressive strength, permeability coefficient, density, Poisson’s ratio and elasticity modulus are examined. Experimental results show that the proposed similar materials can be used for the solid-fluid coupling model test to model rock mass with different permeability coefficients with low and moderate intensity, due to their wide adjustment of parameters, stability of mechanical property, convenience of preparation and low cost. The developed similar materials are applied to simulate the water inrush occurred in the Yonglian tunnel of Jiangxi Province, China. The results show that the mechanical and seepage performances of similar materials satisfy the requirements of model tests, which can not only capture water inrush process of model tunnel, but also reflect the variations of physical fields.

Key words: geomechanical model test, fluid-solid coupling, similar material, cementing agent, rock mechanics