浅埋高强度开采回撤巷道煤柱受载特征及累积损伤机制

Abstract
Figure/Table
References (0)
Related Citation (15)

Download: PDF (2030 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract In order to solve the long-term stability of the shallow-buried coal pillars in withdrawal roadways with high-strength mining effect，the backstoping in the final mining section on the 31409 working face of Jinjie Coal Mine was taken as a project case，and adopting mechanical testing，numerical simulation and on-site monitoring，the stress evolution and accumulated damage mechanism of the coal pillar in the roadway were explored under the superimposed effect of the advanced support pressure on the working face and the progressive loading condition during excavation disturbance. An experiment of coal sample strength weakening and damage failure under three-stage cyclic loading and unloading conditions was designed to reveal the mining stress transfer process in the final mining section，and a numerical model of the mining stress response in the final mining section on the working face was constructed. The research results indicate that：(1) The uniaxial compressive strength of the coal sample under cyclic loading and unloading damage is reduced to 14.14 MPa，while the uniaxial compressive strength of the non-destructive coal sample is 18.40 MPa with a change rate of 23%. There are load fluctuations in the load-bearing section after the peak，which is different from instantaneous damage. The AE parameter of uniaxial compressive of the cumulatively damaged coal sample before the peak load is floating in low values，which is slightly attenuated in the mobility of fracture development compared with that after three loading and unloading cycles. (2) The mining stress in the final mining section experiences three states including repeated superimposition of the advanced support pressure on the coal wall in the conventional mining section, continuous transfer of the support pressure in the adjacent passage section and release of multiple cumulative stresses in the mining run-through section，the passage coal pillar load presents the characteristics of mining-excavation combining influence and uneven distribution in the auxiliary recovery roadway and the goaf，and the critical damage evaluation parameter ω of coal pillar stability is obtained. (3) In the final mining section，the overlying strata or the coal body before and after the goaf contains three zones such as the support pressure attenuation zone，the limit equilibrium zone and the cumulative increase zone. As the working face advances，the influence range of the mining stress extends to the key overburden strata，where the ground pressure is sharp and the coal pillar stress in the roadway accumulates gradually 7.3 MPa about 2.8 times of the original rock stress. This research provides a theoretical basis for ensuring the stability of the supporting system in withdrawal roadways and the safe operation of protective coal pillars.

Key words： mining engineering shallow coal seam withdraw roadway progressive loading coal pillar stability accumulated damage

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	WANG Fangtian1
	2
	SHAO Dongliang1
	2
	NIU Tengchong1
	2
	DOU Fengjin3

Cite this article:

WANG Fangtian1,2,SHAO Dongliang1, et al. Progressive loading characteristics and accumulated damage mechanisms of shallow-buried coal pillars in withdrawal roadways #br# with high-strength mining effect[J]. , 2022, 41(6): 1148-1159.

URL:

https://rockmech.whrsm.ac.cn/EN/Y2022/V41/I6/1148

[1]	黄庆享. 浅埋煤层的矿压特征与浅埋煤层定义[J]. 岩石力学与工程学报，2002，21(8)：1 174-1 177.(HUANG Qingxiang. Ground pressure behavior and definition of shallow seams[J]. Chinese Journal of Rock Mechanics and Engineering，2002，21(8)：1 174-1 177.(in Chinese))
[2]	王方田，屠世浩，张艳伟，等. 冲沟地貌下浅埋煤层开采矿压规律及顶板控制技术[J]. 采矿与安全工程学报，2015，32(6)：877-882.(WANG Fangtian，TU Shihao，ZHANG Yanwei，et al. Ground pressure rules and roof control technology for the longwall mining of shallow seam beneath the gully topography[J]. Journal of Mining and Safety Engineering，2015，32(6)：877-882.(in Chinese))
[3]	王方田，梁宁宁，李岗，等. 复杂应力环境煤柱坝体损伤破坏规律研究[J]. 采矿与安全工程学报，2019，36(6)：1 145-1 152. (WANG Fangtian，LIANG Ningning，LI Gang，et al. Failure evolution mechanism of coal pillar dams in complex stress environment[J]. Journal of Mining and Safety Engineering，2019，36(6)：1 145-1 152. (in Chinese))
[4]	徐祝贺，李全生，李晓斌，等. 浅埋高强度开采覆岩结构演化及地表损伤研究[J]. 煤炭学报，2020，45(8)：2 728-2 739.(XU Zhuhe，LI Quansheng，LI Xiaobin，et al. Structural evolution of overburden and surface damage caused by high-intensity mining with shallow depth[J]. Journal of China Coal Society，2020，45(8)：2 728-2 739. (in Chinese))
[5]	谷拴成，黄荣宾，李金华，等. 工作面贯通前矿压调整时剩余煤柱稳定性分析[J]. 采矿与安全工程学报，2017，34(1)：60-66.(GU Shuangcheng，HUANG Rongbin，LI Jinhua，et al. Stability analysis of un-mined coal pillars during the pressure adjustment prior to working face transfixion[J]. Journal of Mining and Safety Engineering，2017，34(1)：60-66.(in Chinese))
[6]	张杰，陈诚，甄泽，等. 综采工作面末采回撤通道围岩变形控制研究[J]. 煤炭工程，2021，53(6)：40-45.(ZHANG Jie，CHEN Cheng，ZHEN Ze，et al. Deformation control of surrounding rock in the final withdrawal channel of fully mechanized working face[J]. Coal Engineering，2021，53(6)：40-45.(in Chinese))
[7]	李臣，郭晓菲，霍天宏，等. 预掘双回撤通道煤柱留设及其围岩稳定性控制[J]. 华中科技大学学报：自然科学版，2021，49(4)：20-25.(LI Chen，GUO Xiaofei，HUO Tianhong，et al. Coal pillar design of pre-excavated double equipment withdrawal channel and its surrounding rock stability control[J]. Journal of Huazhong University of Science and Technology：Natural Science，2021，49(4)：20-25.(in Chinese))
[8]	张村，韩鹏华，王方田，等. 采动水浸作用下矿井地下水库残留煤柱稳定性[J]. 中国矿业大学学报，2021，50(2)：220-227. (ZHANG Cun，HAN Penghua，WANG Fangtian，et al. The stability of residual coal pillar in underground reservoir with the effect of mining and water immersion[J]. Journal of China University of Mining and Technology，2021，50(2)：220-227.(in Chinese))
[9]	王方田，尚俊剑，赵宾，等. 切顶卸压沿空留巷围岩结构特征及锚索强化支护技术[J]. 岩石力学与工程学报，2021，40(11)：2 296-2 305.(WANG Fangtian，SHANG Junjian，ZHAO Bin，et al. Surrounding rock structural characteristics and its anchor-cable strengthened support technology for the gob-side entry retaining with roof cutting and pressure releasing[J]. Chinese Journal of Rock Mechanics and Engineering，2021，40(11)：2 296-2 305.(in Chinese))
[10]	王中州，李娇娇，秦宾宾，等. 薄基岩破碎顶板工作面回撤通道稳定性及控制研究[J]. 煤矿安全，2021，52(6)：230-236.(WANG Zhongzhou，LI Jiaojiao，QIN Binbin，et al. Study on stability and control of retracement channel with thin bedrock and broken roof[J]. Safety in Coal Mines，2021，52(6)：230-236.(in Chinese))
[11]	贺艳军，张金山，陈凯，等. 预掘回撤通道末采应力叠加效应及围岩破坏规律分析[J]. 重庆大学学报，2022，45(2)：58-67.(HE Yanjun，ZHANG Jinshan，CHEN Kai，et al. Analysis on the superposition effect of stress and the failure law of surrounding rock during the last mining period of pre-excavation return channel[J]. Journal of Chongqing University，2022，45(2)：58-67.(in Chinese))
[12]	张金虎. 破碎顶板回撤通道围岩运动规律和支护适应性研究[J]. 煤炭科学技术，2015，43(12)：28-31.(ZHANG Jinhu. Study on movement law of surrounding rock and support adaptability of the broken roof in return channel[J]. Coal Science and Technology，2015，43(12)：28-31.(in Chinese))
[13]	ZHANG C，WANG F T，BAI Q S. Underground space utilization of coalmines in China：A review of underground water reservoir construction[J]. Tunnelling and Underground Space Technology，2021，107(103657)：1-18.
[14]	牛田瑞，陈健，曹峰. 近距离煤层采动及构造对预掘工作面回撤通道的影响[J]. 煤炭科学技术，2020，48(增2)：47-52.(NIU Tianrui，CHEN Jian，CAO Feng. Influence of coal mining and tectonic on withdrawal exit roadway pre-excavating in contiguous coal seams[J]. Coal Science and Technology，2020，48(Supp.2)：47-52.(in Chinese))
[15]	杨尚，宁建国，商和福，等. 浅埋近距离煤层工作面末采阶段等压原理与应用[J]. 煤矿安全，2019，50(11)：149-153.(YANG Shang，NING Jianguo，SHANG Hefu，et al. Isobaric principle and application of end-mining stage in shallow buried near-distance coal seam working face[J]. Safety in Coal Mines，2019，50(11)：149-153.(in Chinese))
[16]	李杰，王军，曹建云. 8.8 m采高工作面主回撤通道顶板支护技术研究[J]. 煤炭科学技术，2019，47(增2)：185-187.(LI Jie，WANG Jun，CAO Jianyun. Study on the support technology of the main retracement channel roof for the 8.8 m mining height[J]. Coal Science and Technology，2019，47(Supp.2)：185-187.(in Chinese))
[17]	LI C，WU Z，ZHANG W，et al. A case study on asymmetric deformation mechanism of the reserved roadway under mining influences and its control techniques[J]. Geomechanics and Engineering，2020，22(5)：449-460.
[18]	许家林，钱鸣高. 覆岩关键层位置的判别方法[J]. 中国矿业大学学报，2000，29(5)：21-25.(XU Jialin，QIAN Minggao. Method to distinguish key strata in overburden[J]. Journal of China University of Mining and Technology，2000，29(5)：21-25.(in Chinese))