Model experimental investigation on the effects of rockburst on gently inclined structural planes under gradient stresses LIN Manqing1,2, LU Xianglong1,2, XIA Yuanyou3, ZHANG Lan3, LIAO Qi1,2, YANG Tao1,2

Deep excavation caused by the surrounding rock gradient stress and the natural endowment of the rock layer of slow inclination of the hard structural planes is an important factor affecting the characteristics of the rock explosion. In this paper, with the aid of gas-liquid composite loading rockburst simulation device on the prefabricated rock specimens containing different hard slowly inclined structural planes of large size (400×600×1000 mm) class rock body test three-way loading - unloading of a single side of the stress gradient loading rockburst test, through the DIC (digital image correlation), acoustic emission, infrared radiation and high-speed photography and other means of monitoring, to study the evolution of the specimens containing slowly inclined structural planes features and damage mechanisms. Research containing gently inclined structure test piece rockburst evolution characteristics and damage mechanism. The results show that the existence of gently inclined structural planes has a controlling effect on the damage mode of the specimen, which greatly limits the boundary and scope of the rockburst crater and accelerates the occurrence of rockburst. The location of the specimen rockburst is mainly distributed in the region between the specimen structural surface, and the infrared radiation value and DIC strain field in this region are significantly higher than the other locations of the unloading surface before the damage. As the inclination angle of the gently inclined structural planes increases, the peak and cumulative acoustic emission energy of the specimen increases, resulting in an increase in the proportion of shear damage to the total damage and an increase in the intensity of the rockbursts that are spawned.The research results can provide an important reference for disaster prevention and control and management of deeply buried high-stress underground engineering.