Failure characteristics and the damage evolution of a composite bearing structure in pillar-side cemented paste backfilling  

作　　者：Boqiang Cui Guorui Feng Jinwen Bai Gaili Xue Kai Wang Xudong Shi Shanyong Wang Zehua Wang Jun Guo 

机构地区：[1]College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China [2]Key Laboratory of Shanxi Province for Mine Rock Strata Control and Disaster Prevention,Taiyuan 030024,China [3]Shanxi Coking Coal Group Co.,Ltd.,Taiyuan 030024,China [4]Priority Research Centre for Geotechnical Science and Engineering,School of Engineering,The University of Newcastle,Callaghan,NSW 2308,Australia

出　　处：《International Journal of Minerals,Metallurgy and Materials》2023年第8期1524-1537,共14页矿物冶金与材料学报（英文版）

基　　金：supported by the Shanxi Science and Technology Major Project (No.20201102004);the Distinguished Youth Funds of National Natural Science Foundation of China (No.51925402);the National Natural Science Foundation of China (Nos.52174125,52004171,and 51904203);the Outstanding Youth Cultivation Project in Shanxi Province,China (No.202103021222008);the Key Science and Technology Innovation Team of“1331”Project in Shanxi Province,China,and the Open Fund Project of Key Laboratory of Mining Disaster Prevention and Control (No.MDPC202004)。

摘　　要：A backfilling body-coal pillar-backfilling body(BPB)structure formed by pillar-side cemented paste backfilling can bear overburden stress and ensure safe mining.However,the failure response of BPB composite samples must be investigated.This paper examines the deformation characteristics and damage evolution of six types of BPB composite samples using a digital speckle correlation method under uniaxial compression conditions.A new damage evolution equation was established on the basis of the input strain energy and dissipated strain energy at the peak stress.The prevention and control mechanisms of the backfilling body on the coal pillar instability were discussed.The results show that the deformation localization and macroscopic cracks of the BPB composite samples first appeared at the coal-backfilling interface,and then expanded to the backfilling elements,ultimately appearing in the coal elements.The elastic strain energy in the BPB composite samples reached a maximum at the peak stress,whereas the dissipated energy continued to accumulate and increase.The damage evolution curve and equation agree well with the test results,providing further understanding of instability prevention and the control mechanisms of the BPB composite samples.The restraining effect on the coal pillar was gradually reduced with decreasing backfilling body element's volume ratio,and the BPB composite structure became more vulnerable to failure.This research is expected to guide the design,stability monitoring,instability prevention,and control of BPB structures in pillar-side cemented paste backfilling mining.

关 键 词：backfilling body-coal pillar-backfilling body composite structure digital speckle correlation method uniaxial compression deformation characteristics damage evolution 

分 类 号：TD823.7[矿业工程—煤矿开采]