DOI: 10.11799/ce202510008
Staged fracturing with super-long horizontal boreholes for rock burst prevention in coal seams under thick and hard roofs
ZHAO Qian
ZHOU Jinlong
MA Ping
XIA Yongxue
GAO Jingyong
DU Taotao
FU Qiang
WU Jianhong
Abstract：Thick and hard roofs is a key factor inducing rock burst in coal mining,and staged fracturing with super-long horizontal boreholes is an effective means for destressing the thick and hard roofs and prevent rock burst.In order to analyze the effect of such means in controlling rock burst under thick and hard roofs,the No.11-3107 working face of a coal mine in Ordos was taken as the research object,and the means of microseismic monitoring,support working resistance monitoring and surface subsidence monitoring were comprehensively applied.The results show that staged fracturing with super-long horizontal borehole has significant effects of destressing and weakening of rock mass.The energy and frequency of microseismic events,as well as the supports pressure in the working face declined greatly after the technology was implemented,and the surface subsidence showed a trend of increasing.Specifically,the average daily energy and number of microseismic events declined by 67.50%(1.1×105 J)and 33.75%(27)respectively,and the supports pressure dropped by 21.5%,while the surface subsidence increased by about 87.59%.The integrity of the roof was weakened after the staged fracturing,so that it broke and collapsed in time after coal mining,dissipating the energy accumulated in the roof,reducing the overhanging area,and the dynamic load during the mining period,thus bring down the risk of rock burst induced by breakage of the thick and hard roofs.The proposed technology has a positive effect on reducing the rock burst risk under thick and hard roof,and the results of the study can provide a reference for controlling this type of disasters.
Keywords：thick and hard roofsrock burstsuper-long horizontal borehole staged fracturingmicroseismic monitoringevaluation of pressure relief effect
Publication Date：2025-10-20
Online Publishing Date：2025-11-18(First online date of this platform, not the publication date of the document)
Pages：8( 60-67 )