考虑围岩性质和应力水平的深埋并行隧道合理间距确定

2020-03-31 19:56:38王瑞鹏张建勇李新成
科技创新导报 2020年34期

王瑞鹏 张建勇 李新成

摘  要:为研究复杂环境下深埋并行隧道合理间距,基于深埋并行隧道围岩的弹塑性应力解,采用广义Heok-Brown强度准则的无量纲形式,建立了考虑围岩性质和应力水平的深埋条件下并行隧道合理间距力学模型,归纳出不同埋深、开挖半径、地质强度指标GSI和岩体单轴抗压强度四种因素影响深埋并行隧道合理间距确定。研究结果表明:同一埋深条件下,岩石的坚硬程度和岩体质量共同决定并行隧道合理间距。

关键词:围岩性质  深埋  并行隧道  间距

Abstract: In order to study the reasonable spacing of deep buried parallel tunnels in complex environment ,based on the elasto-plastic stress solution of the surrounding rock of the deep-buried parallel tunnel and the dimensionless form of the generalized Heok-brown strength criterion, the reasonable spacing mechanics model of the parallel tunnel under the deep burial condition considering the surrounding rock type and the stress level is established,Four factors, such as different buried depth, excavation radius, geological strength index GSI and uniaxial compressive strength of rock mass, affect the determination of reasonable spacing of deep parallel tunnels. The results show that under the same depth condition, the rock hardness and rock mass quality determine the reasonable spacing of parallel tunnels.

Key Words: Properties of surrounding rock ; Deep burial; Parallel tunneling; Spacing

深埋并行隧道合理间距一直是水利、交通和矿山领域研究的热点问题之一。近年来,受地形、地质条件和资源开发深度等因素的制约,隧道埋深不断增大,一些并行隧道夹岩墙由于间距设计不合理出现塑性贯穿破环,给工程施工带来极大的安全隐患和经济损失。许多学者在确定并行隧道合理间距方面开展了理论解析,数值模拟和模型实验研究:苏锋等[1]利用解析延拓法及Schwarz交替法求解出弹性半空间深埋双隧道的应力解和位移解的解析表达式,并采用数值分析验证结果的可靠性;宋伟超等[2]结合复变函数和考虑中间主应力效应的D-P屈服准则,建立相邻水平并行隧道合理间距的力学模型,以2倍的塑性区临界贯穿半径作为合理间距,并采用数值模拟验证其可靠性;Barla 和Ottoviani[3]通過数值模拟方法得出,并行隧道中间岩柱厚度大于1倍开挖直径时,两隧道之间的影响可以……

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