Solution of D-P Criterion of Plastic District of Surrounding Rock of Roadway
ZHAI Suo-ye 1 , HUO Xian-guo 2 (1. College of Engineering, SUST··, Taian, Shandong 271021, China; 2. Liangzhuang Mine of Shandong Xinwen Mine Group, Xintai 271219, China)
Considering that the yield of surrounding rock of roadway is related to the middle principal stress, the analytic formula for radius of plastic district and stress of round roadway have been put out by adopting the Druker-Prager criterion. The result shows that the plastic area radius of surrounding rock of roadway increases after taking account of the middle principal stress, it is proved that the middle principal stress has a certain influence to the plastic district. So this theoretical formulation is the complement of the past theoretical achievement, and has offered a kind of new method for theoretical calculation of plastic area of surrounding rock of roadway.