Disaster mechanism of karst water bursting in mine

WANG Wei-jun; ZHAO Yan-Lin; LI Qing-feng; PENG Wen-qing

Abstract：Based on water disasters in Qiyi Mine in Loudi City Hunan Province,by comprehensive use of the theories of geometric damage mechanics and rock fluid mechanics, the seepage-damage-fracture coupling disaster mechanism of karst water bursting in mine was studied and the model of seepage-damage-fracture coupling (extended FLAC3D model)was established. The seepage-damage-fracture coupling analysis on the disaster formation process of karst water bursting in Qiyi Mine was shown. The evolution law of surrounding rock seepage field and fracturing damage in rock pillar under combined action of mining influence and seepage was studied. Coupling analysis shows that with the coupling effect of high body force of seepage and secondary stress in surrounding rock, hydraulic fracturing in rock pillar which is in damage state results in karst water bursting. Coupling analysis aslo shows that sudden changes of permeability coefficient,body force of seepage and displacement occur in coupling analysis of karst water bursting in mine. Countermeasures to prevent high risk in karst water bursting filling-type karst cave and reasonable leaving water prevention coal rock pillar were discussed.