Similar simulation test of the mechanical properties of layered composite rock mass

Most of the mine roadways in China are located in layered rock mass. To study the mechanical properties of a layered rock mass, the uniaxial compression test was carried out on the layered composite rock mass composed of sand and paraffin. The results showed that the locations of the high‐ and low‐strength rocks were independent of the strength of the layered composite rock. The main failure site was not affected by the combination mode. Failure was mainly concentrated in the low‐strength rock. The strengths of low‐ and high‐strength rocks determined the lower and upper limits of the strength of the layered rock, respectively. When the thickness of the layered high‐strength composite rock was >60%, the layered composite rock strength tended to be high; conversely, layered composite rock strength lowered the rock strength, and with increasing thickness, the layered composite rock strength was significantly enhanced. From the perspective of energy conversion, the effect of the thickness of the high‐strength rock mass on the strength of the layered composite rock mass was analyzed. The graphical depicts the influence of different factors on the mechanical properties of layered composite rock blocks. The results show that the quantitative change caused a qualitative change; that is, a thickness limit was observed. Below this limit, the composite tended to be a low‐strength test block. Beyond this limit, the strength of the layered composite rock mass tended to be a high‐strength test block. With this increase in thickness, the strength of the layered composite rock mass significantly increased.