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.