煤田地质与勘探2025，Vol.53Issue(2)：147-159,13.DOI:10.12363/issn.1001-1986.24.05.0313
饱和浸水过程矸石胶结充填体强度及损伤特征
Strength and damage characteristics of cemented gangue backfill during saturated immersion
摘要
Abstract
[Objective]Under the influence of backfill slurry,water inrushes in mining face,and water accumulation in goaves,the water content in cemented gangue backfill varies with the immersion time,thus altering the bearing perform-ance of the backfill.Investigating the strength and damage characteristics of cemented gangue backfill during saturated immersion is crucial for maintaining the stability of the backfill and ensuring the safety of coal mines.[Methods]Using uniaxial compression tests and scanning electron microscopy(SEM)of cemented gangue backfill during saturated im-mersion,this study analyzed the law of changes in the backfill strength under varying immersion times.Based on the statistical distribution of microelement strength,this study established a piecewise damage constitutive model for the ce-mented gangue backfill in the pre-peak stage.Using SEM,this study revealed the mechanism underlying the strength weakening of the cemented gangue backfill during saturated immersion.[Results and Conclusions]The results indicate that during saturated immersion,the cemented gangue backfill under uniaxial compression exhibited significant four-stage stress-strain curves.In the compaction and closure stage of pores and fractures,the maximum strain/stress and the strain at the peak stress point were positively correlated with the immersion time,while the peak stress and modulus of elasticit y were negatively correlated with the immersion time.With an increase in the immersion time,the primary fail-ure morphologies of the cemented gangue backfill transitioned from shear failure to tension-shear conjugate failure,fi-nally shifting to longitudinal tensile failure,with the failures concentrated in the central part of the cemented gangue backfill.This study established a piecewise damage constitutive model for the cemented gangue backfill in the compac-tion and closure stage of pores and fractures that considered the maximum stress and strain,modulus of elasticity,peak stress,and strain at the peak stress point.This model was verified using test data,indicating that the model-derived theor-etical curves were roughly consistent with the test curves.Subjected to the surface tension and lubrication of water,as well as mineral dissolution,the cemented gangue backfill during saturated immersion manifested a three-stage strength weakening mechanism.As the cemented gangue backfill was saturated with water,its strength continued to decrease at a decreasing rate.The results of this study will provide certain data for coal mining based on cemented gangue backfill in environments with water-rich goaves.关键词
饱和浸水/矸石/胶结充填体/单轴压缩/分段损伤/本构模型/强度弱化机理Key words
saturated immersion/gangue/cemented backfill/uniaxial compression/piecewise damage/constitutive mod-el/strength weakening mechanism分类
矿业与冶金引用本文复制引用
于祥,杨科,何祥,侯永强,文志强,张连富..饱和浸水过程矸石胶结充填体强度及损伤特征[J].煤田地质与勘探,2025,53(2):147-159,13.基金项目
国家自然科学基金重点项目(52130402) （52130402）
安徽省煤炭安全精准开采工程实验室开放课题基金项目(ESCMMP202402) （ESCMMP202402）
安徽省关闭/废弃矿井资源开发利用工程研究中心开放基金项目(EUCMR202208) （EUCMR202208）
甘肃省青年科技基金项目(24JRRA1012) （24JRRA1012）
甘肃省青年博士支持项目(2024QB-103) （2024QB-103）
