采矿与安全工程学报 ›› 2015, Vol. 32 ›› Issue (4): 537-543.

• 论文 • 上一篇    下一篇

早强混凝土实验与极软岩巷道钢管混凝土支架应用研究

  

  1. 1.中国矿业大学(北京)力学与建筑工程学院,北京 100083; 2.山东科技大学矿业与安全工程学院,山东青岛 266590
  • 收稿日期:2014-08-17 出版日期:2015-07-15 发布日期:2019-09-02
  • 作者简介:高延法(1962—),男,山东省滕州市人,教授,博士生导师,从事矿山岩体力学、深井软岩巷道支护等方面的研究。
  • 基金资助:

    国家自然科学基金项目(51474218,51134025)

Early strength concrete experiment and applied research of early strength concrete-filled steel tubular supports in extremely soft rock roadways

  • Received:2014-08-17 Online:2015-07-15 Published:2019-09-02

摘要: 针对极软岩巷道支护中普通型钢管混凝土支架在核心混凝土尚未有效凝固时就被压坏的问题,进行了早强混凝土的配比实验,结合实验成果研发了早强型钢管混凝土支架,通过理论计算对比分析了早强型和普通型支架的早期支护反力。最后以北皂煤矿二煤顶板巷道为工程背景,设计了基于早强型钢管混凝土支架的复合支护方案,并对支护效果进行数值模拟,最终应用于工程实践。结果表明:早强混凝土坍落度大于220 mm,缓凝3 h 以上,1 d 抗压强度大于40 MPa, 3 d 抗压强度大于49.9 MPa,满足泵送要求和早强要求;早强型钢管混凝土支架1,3,7 d 的支护反力分别可达普通型支架的1.68,1.4,1.26 倍,且后期仍能缓慢增长。数值模拟和工程实践充分证明基于早强型钢管混凝土支架的复合支护能够有效抑制极软岩巷道的早期快速收敛变形,并能维持巷道的长期稳定。

关键词: 钢管混凝土支架, 极软岩巷道, 早强混凝土, 配合比, 复合支护

Abstract: When ordinary concrete-filled steel tubular supports (CFST supports) are used in extremely soft rock roadway, they are likely to be destroyed before the core concrete forms a larger strength. To solve this problem, the mixing experiment of early strength concrete has been carried out at first and then researchers have developed the early strength CFST supports based on previous experimental results. Further more, early supporting counter-force of early strength CFST supports and ordinary CFST supports have been contrastively analyzed by using theoretical calculation. At last, composite supports scheme based on early strength CFST supports has been designed and simulated with Beizao mine roof roadway as the engineering background, which has been used in engineering practice ultimately. Research results have indicated that the initial slump surpasses 220 mm, and the retarding time surpasses 3 h, and its 1 d compressive strength after final set surpasses 40 MPa, and that 3 d compressive strength surpasses 49.9 MPa,which have met pumping and early strength requirements; the 1 d,3 d and 7 d supporting counter-force of early strength CFST supports are 1.68 times,1.4 times and 1.26 times of the ordinary CFST supports, and it can still grow slowly in the late stage; numerical simulation and engineering application have sufficiently proved that the composite supports based on early strength CFST supports can effectively inhibit the convergence deformation of the extremely soft rock roadway in the early time and ensure the long-term stability of the roadway.

Key words: concrete-filled steel tubular supports (CFST supports), extremely soft rock roadway, early strength concrete, mix proportion, composite support