Energy analysis of synergetic anchorage with bolt and anchoring cable
Zhang Xinguo1, Dang Pengyuan2, Zhu Chuchu2
1. Chengjiao Mine of Henan Energy and Chemical Group Yongmei Company，Shangqiu 476600, China;
2. School of Mechanics and Civil Engineering, China University of Mining and Technology, Xuzhou 221008, China
Abstract： The deformation, failure and instability of surrounding rock in underground engineering are always accompanied by the transformation and transfer of energy. The application of support body has a certain control effect on the deformation and instability of surrounding rock, and it must also affect the transformation and transfer of energy in anchorage body and surrounding rock. Based on Mohr-Coulomb criterion, the distribution and influence factors of elastic strain energy and plastic strain energy in surrounding rock after excavation of circular roadway was analyzed. It was pointed out that among the mechanical parameters of surrounding rock in fractured zone, cohesion had greater influence on energy distribution than internal friction angle. Grouting and improving the prestress of bolt could increase the cohesion of rock mass. The increase of cohesion could reduce the range of broken zone, but it would aggravate the agglomeration of plastic energy. It was necessary to provide uniform supporting force for anchor body with combined anchor cable to weaken the agglomeration effect of plastic energy of surrounding rock. In order to ensure that the anchor rod and the anchor cable worked together, the prestress must be matched with each other, and the prestress of the anchor rod and the anchor cable should be matched with the elastic modulus of the anchor rod. While reducing the scope of the crushing zone, the degree of agglomeration of plastic failure energy was weakened, the elastic energy of surrounding rock was reduced, and the surrounding rock was in a stable state of less crushing, uniform crushing and low energy.
