Experimental study on shear mechanical behaviors of interface between two kinds of media

Direct shear tests are carried out to investigate the influence of the interface on the mechanical behaviors of bi-material and the bi-body.A special specimen,casted with both mortar and concrete and formed irregular asperities in the interface between bi-material is employed to simulate the interaction of structural body and geo-body.According to the direct shear tests,the failure pattern and stress-displacement curves of bi-material specimens and bi-body specimens are analyzed.The main results are as follows:the cohesion effect and normal stress have a key influence on the mechanical behaviors of the interface;and under the middle-and low-grade normal stresses,the shape factor λ has an important influence on the shear mechanical properties of the interface of bi-body.However,under the high normal stress,the shear mechanical properties of the interface are determined by the strength of attenuating medium.Because of the difference of the failure pattern force form,under the middle-and low-grade normal stresses,the peak shear strength of the bi-material specimens is larger than that of the bi-body specimens.However,under the high normal stress,the result is opposite.