软岩巷道顶、帮、底全支全让O型控制力学模型及工程实践

软弱岩体的阶段性、持续性流变,导致软岩巷道围岩深度破坏和支护失效。软岩巷道顶、帮、底三者在围岩系统稳定过程中所起的作用不同,软岩巷道围岩稳定性控制应做到整体性和协调性支护。在分析巷道顶、帮、底相互作用效应基础上,针对软岩巷道强流变四周均表现出大变形的破坏特征,提出了全断面、全支全让O型封闭控制的支护原理。该原理强调,开挖初期就应对软岩巷道顶、帮、底全断面进行强力支护,同时全断面又适时让压,在高阻支护力作用下又能适当释放围岩应力,达到对软岩巷道的整体性和协调性控制。通过力学模型对软岩巷道围岩塑性区范围和表面位移与支护力的作用关系进行了分析计算,得出巷道围岩变形破坏与支护力呈负相关关系。工程实践表明,采用该支护原理有效控制了深部软岩巷道的大变形。研究成果对类似工程实践具有一定的参考借鉴价值。

Roof and support and bottom yielding support with whole section and O-shape control principle for soft rock roadway and engineering practice

Due to the phasic and continuous rheology of soft rock, failure of surrounding rock and supports of soft rock roadway usually happened. Based on the analysis of interaction effect between roof and support and bottom, the support principle of yielding support with whole section and O-shape control is proposed for the large deformation roadway in deep soft rock. Firstly, the roadway in deep soft rock should be supported with whole section and high strength to control initial deformation. Meanwhile, effective measures releasing pressure of surrounding rock with whole section properly, surrounding rock of roadway would be controlled to good stability, making sure that the soft rock roadway could be controlled coordinately and consistently. Through the mechanical model, relations of plastic zone and surface displacement of the soft rock roadway with supporting force are calculated; the relationship between surrounding rock deformation and support force is negative. Engineering practice showed that the large deformation of roadway in deep soft rock could be controlled efficiently with this support principle. Research results have a good value to similar engineering.