采矿与安全工程学报 ›› 2016, Vol. 33 ›› Issue (3): 460-466.

• 论文 • 上一篇    下一篇

卸压开采影响下回采巷道支护强度量化计算方法探讨

  

  1. 1.山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地,山东 青岛 266590; 2.安徽理工大学煤矿安全高效开采省部共建教育部重点实验室,安徽 淮南 232001; 3.山东科技大学矿业与安全工程学院,山东 青岛 266590
  • 收稿日期:2014-09-14 出版日期:2016-05-15 发布日期:2016-06-03
  • 作者简介:于凤海(1987—),男,山东省临朐县人,博士研究生,从事矿山岩体力学与巷道支护方面的研究。
  • 基金资助:

    国家自然科学基金项目(51274133,51474137,51474136);高等学校博士学科点专项科研基金项目(20123718110013);山东省泰山学者工程专项经费项目;山东省科技发展计划项目(2014GSF120002);煤矿安全高效开采省部共建教育部重点实验室开放基金项目 (JYBSYS2014202)

Study on quantitative calculation method of mining roadway supporting intensity under depressurized mining

  • Received:2014-09-14 Online:2016-05-15 Published:2016-06-03

摘要: 为实现卸压开采状况下回采巷道支护强度的定量化确定,采用理论分析、数值模拟及现场试验相结合的方法,探讨了卸压开采状况下底板应力分布特征,提出了卸压开采影响系数,给出了卸压开采影响下回采巷道支护强度量化确定方法,并进行了现场工程实践。研究结果表明:卸压开采后煤层底板可划分为底板破裂区(弧形)、应力降低区(抛物线形)、应力增高区(椭圆形)和原岩应力区,应力降低区深度为采空区宽度的 60%~70%,应力增高区宽度为 3.0 倍外应力场宽度,深度范围约为 5.0 倍外应力场宽度。卸压开采影响系数取值范围为 0~1.0,卸压开采影响重点区域为底板 40 m 深度范围内。通过现场监测表明,受卸压开采影响,下层煤回采巷道所需支护强度降低,当支护间距由 600 mm 增加至 800 mm,顶底板移近量反而减小了 46.5%,两帮移近量减小了 46.7%。考虑卸压开采影响,使得回采巷道支护强度确定更加合理。

关键词: 卸压开采, 回采巷道, 卸压开采影响系数, 支护强度, 定量化

Abstract: In order to realize the quantitative supporting intensity of mining roadway under depressurized mining, characteristics of floor stress distribution were discussed, coefficient of depressurized mining was proposed, and the calculation method about supporting intensity of roadway was given in this paper based on theoretical analysis, numerical simulation and field test. The results have shown that the floor zone can be divided into fractured zone (arc), decreased stress zone (parabola), increased stress zone (oval), and original stress zone. Decreased stress zone depth is 60%-70% times the width of coal face, increased stress zone is 3 times the width and 5 times the depth of external stress field length. The range about coefficient of depressurized mining is 0-1.0 and the depth of key influence areas is about 40 m. According to the field monitoring, required supporting strength of gateway decreased for depressurized mining. Although the supporting spacing increases from 600 mm to 800 mm, the roof to floor convergence decreases 46.5%, and the deformation of two roadsides reduces by 46.7%. It is rational determination to consider the effect of depressurized mining for roadway support.

Key words: depressurized mining, mining roadway, coefficient of depressurized mining, supporting intensity, quantification