煤田地质与勘探2025，Vol.53Issue(10)：101-115,15.DOI:10.12363/issn.1001-1986.24.12.0777
煤矿连采连充欠接顶区覆岩稳定性数值模拟研究
Numerical simulations of the overburden stability in underfilling zones during continuous min-ing and continuous backfilling of coal mines
摘要
Abstract
[Objective and Method]Coals serve as a predominant energy source in China.However,coal mining has resulted in increasingly pronounced ecological issues such as ground subsidence and solid waste accumulation.Al-though the continuous mining and continuous backfilling(CMCB)technology allows for efficient resource recovery and ecological protection through backfilling with coal-based solid waste,the issue of insufficient roof-contact backfilling(termed underfilling)poses a serious threat to the overburden stability during mining.Given the unclear mechanisms be-hind the influence of coupled multiple factors of underfilling zones in current research,this study constructed three-di-mensional numerical models using the 3DEC discrete element software based on the engineering background of a mine with backfill using aeolian sand paste-like filling materials in Yulin,Shanxi Province.Eight operating conditions were designed to compare the impacts of the underfilling zone size,roof conditions,and support conditions on overburden dis-placement,stress distribution,and surface deformation.Furthermore,a mechanical model was developed based on the elastic foundation beam theory to calculate the overburden displacement during the mining of a strip coal pillar under the influence of underfilling zones.[Results and Conclusions]With the expansion of underfilling zones(volume ratio:≥10％),the overburden displacement and the surface subsidence increased significantly.Most especially,the expansion produced a more significant impact on the overburden stability in the presence of a 20-m-width underfilling zone on each side of the mining face.The development of roof fractures further aggravated the overburden instability,leading to more pronounced overburden displacement and stress concentration.Notably,in the presence of a 20-m-width underfilling zone on each side of the mining face and the development of roof fractures,the maximum overburden displacement and peak stress post-mining increased by 40.3％and 44.5％,respectively,compared to those of the control group with no roof fracture.This seriously threatens mining safety.Although support failure also led to more pronounced overburden displacement and stress concentration,it exerted relatively limited influence.Under the operating condition with the presence of a 20-m-width underfilling zone on each side of the mining face and support failure,the maximum overbur-den displacement and peak stress post-mining were 2.1％and 5.6％,respectively,higher than those under intact support.In practical backfilling operations,the extent of underfilling zones can be effectively reduced by optimizing the roof-contact backfilling process.Meanwhile,enhanced control over fractured zones is required during mining to mitigate their adverse effects on the overburden stability.Additionally,sound support conditions can effectively reduce the overbur-den displacement and stress concentration in underfilling zones.关键词
充填开采/数值模拟/欠接顶区/覆岩稳定性Key words
backfill mining/numerical simulation/underfilling zone/overburden stability分类
矿山工程引用本文复制引用
刘浪,罗屹骁,朱梦博,何军,屈慧升,段怀军,蔚保宁,刘智振..煤矿连采连充欠接顶区覆岩稳定性数值模拟研究[J].煤田地质与勘探,2025,53(10):101-115,15.基金项目
国家自然科学基金项目(52204175,52378264) （52204175,52378264）
陕西省两链融合重点专项项目(2023-LL-Qy-07) （2023-LL-Qy-07）
