采矿与安全工程学报 ›› 2015, Vol. 32 ›› Issue (2): 227-232.

• 论文 • 上一篇    下一篇

西部浅埋煤层煤样承载力及冲击倾向特征研究

  

  1. 中国矿业大学深部岩土力学与地下工程国家重点实验室,力学与建筑工程学院,江苏 徐州 221116
  • 出版日期:2015-03-15 发布日期:2015-06-23
  • 作者简介:苏海健(1988—),男,江苏省启东市人,博士研究生,从事岩石力学与工程等方面的研究。
  • 基金资助:
    国家重点基础研究发展计划(973)项目(2013CB036003);江苏省普通高校研究生科研创新计划项目(CXZZ13_0935);国家自然科学基 金项目(51374198)

Research on bearing capacity and burst proneness of coal samples from western shallow-buried coal seam

  • Online:2015-03-15 Published:2015-06-23

摘要: 浅埋深、厚煤层、窄煤柱是我国西部浅埋煤层的典型赋存特征。为考察温度、水、尺度对西部浅埋煤层煤样承载力及冲击倾向特征的影响规律,分别对饱水及饱水风干、25~250 ℃之间4 种温度水平及3 种不同高径比煤样进行室内单轴压缩试验。试验结果表明:1) 从自然状态-饱水- 饱水后风干,煤样峰值强度和弹性模量急剧降低,而峰值应变逐渐增大,煤样破坏程度愈渐剧烈,冲击倾向特征减弱;2) 随着温度的升高,煤样峰值强度、峰值应变和弹性模量均呈现先增大后减小的趋势,在100 ℃出现临界点,此时煤样在加载过程中崩溅剧烈,冲击倾向性加剧;温度继续升高至250 ℃,煤样承载力及冲击倾向性逐渐弱化;3) 随着高径比的增加,煤样峰值强度、峰值应变及弹性模量均呈现衰减趋势,煤样变形及破坏程度减弱,而冲击倾向特征增强。

关键词: 西部浅埋煤层, 饱水, 高温处理, 高径比, 冲击倾向

Abstract: Shallow buried depth, thick coal seam and narrow coal pillar are typical occurrence characteristics of western shallow-buried coal seam in China.The uniaxial compression test of coal samples in water-saturated and air-dried conditions, in four temperature levels between 25 ℃ and 250 ℃, and of three different kinds of ratio of height to diameter has been conducted respectively in order to investigate the influence law of temperature, water, and dimension on the bearing capacity and burst proneness of coal samples from western shallow-buried coal seam.The results show that: 1) From natural state-water saturation-seasoned state, peak strength and the modulus of coal samples decrease sharply while the peak strain increases gradually.The damage extent becomes more and more severe while the burst proneness weakens. 2) With the gradual increase of the temperature, peak strength, peak strain and the modulus of coal samples all first increase then decrease, and all arise the critical point when the temperature is 100 ℃, at this time burst proneness of coal samples aggravates with severe splashing during the loading process.However, both the bearing capacity and burst proneness weaken gradually as the temperature continues to rise to 250 ℃. 3) With the increase of the ratio of height to diameter, peak strength, peak strain and the modulus of coal samples all show the attenuation trend.Deformation and the damage extent weaken while the burst proneness strengthens.

Key words: western shallow-buried coal seam, saturation, high temperature treatment, the ratio of height to diameter, burst proneness