Experiment on acoustic emission response and damage evolution characteristics of polymer-modified cemented paste backfill under uniaxial compression

作     者：Shenyang Ouyang Yanli Huang Nan Zhou Ming Li Xiaotong Li Junmeng Li Fei Ke Yahui Liu Shenyang Ouyang;Yanli Huang;Nan Zhou;Ming Li;Xiaotong Li;Junmeng Li;Fei Ke;Yahui Liu

作者机构：State Key Laboratory of Coal Resources and Safe MiningSchool of MinesChina University of Mining and TechnologyXuzhou 221116China Xinjiang Institute of EngineeringUrumqi 830000China Henan Energy Chemical Group Co.Ltd.Zhengzhou 450000China 

出 版 物：《International Journal of Minerals,Metallurgy and Materials》 (矿物冶金与材料学报（英文版）)

年 卷 期：2023年第30卷第8期

页      面：1502-1514页

核心收录：

学科分类：081901[工学-采矿工程] 0819[工学-矿业工程] 08[工学] 0703[理学-化学] 

基　　金：supported by the National Natural Science Foundation of China (Nos.52022107,52174128,and 52104103) the Natural Science Foundation of Jiangsu Province (Nos.BK20190031 and BK20210499) the“Tianshan Innovation Team Plan”Project (No.2021D14016) the Xinjiang Key Research and Development Special Project (No.2022B03028-3) the Xinjiang Central Guidance Local Fund Project。 

主　　题：polymer cemented paste backfill mechanical strength acoustic emission 

摘      要：The mechanical properties of cemented paste backfill(CPB)determine its control effect on the goaf roof.In this study,the mechanical strength of polymer-modified cemented paste backfill(PCPB)samples was tested by uniaxial compression tests,and the failure characteristics of PCPB under the compression were analyzed.Besides,acoustic emission(AE)technology was used to monitor and record the cracking process of the PCPB sample with a curing age of 28 d,and two AE indexes(rise angle and average frequency)were used to classify the failure modes of samples under different loading processes.The results show that waterborne epoxy resin can significantly enhance the mechanical strength of PCPB samples(when the mass ratio of polymer to powder material is 0.30,the strength of PCPB samples with a curing age of 28 d is increased by 102.6%);with the increase of polymer content,the mechanical strength of PCPB samples is improved significantly in the early and middle period of curing.Under uniaxial load,the macro cracks of PCPB samples are mostly generated along the axial direction,the main crack runs through the sample,and a large number of small cracks are distributed around the main crack.The AE response of PCPB samples during the whole loading process can be divided into four periods:quiet period,slow growth period,rapid growth period,and remission period,corresponding to the micro-pore compaction stage,elastic deformation stage,plastic deformation stage,and failure instability stage of the stress-strain curve.The AE events are mainly concentrated in the plastic deformation stage;both shear failure and tensile failure occur in the above four stages,while tensile failure is dominant for PCPB samples.This study provides a reference for the safety of coal pillar recovery in pillar goaf.