DEVELOPMENT AND APPLICATION OF A NEW SIMILAR MATERIAL FOR UNDERGROUND ENGINEERING FLUID-SOLID COUPLING MODEL TEST

A new similar material for fluid-solid coupling has been developed through hundreds of compounding tests based subsea on the theory of fluid-solid coupling on geomechanics model test and the exploration data of the Qingdao Kiaochow Bay tunnel.It is mixed with sand,barite powder,talc powder,cement,vaseline and silicone oil.The effect of different mixing ratios on the properties of the samples has been systematically studied and the main components controlling the material properties have been determined through large numbers of laboratory tests.The test results indicate that the new material s strength and elastic modulus are controlled by cement and vaseline;its cohesion is mainly effected by vaseline;its permeability coefficient can be adjusted by the ratio of vaseline and silicone oil.Water retention and compactness improvement are also the role of silicone oil.Deformation characteristics and permeability of the material are regulated by different compositions and the interaction is slight.So the properties of the material can be controlled comprehensively.The new material can simulate low-strength and medium-strength rock materials with different permeabilities,which is an ideal similar material for fluid-solid coupling.This material has been used in the Qingdao Kiaochow Bay subsea tunnel water-inflow model test,and its mechanical properties and permeability has met the test requirements.The new material ensures good test results.