大断面软岩巷道底鼓机理及控制对策研究

Study on the Mechanism and Controlling Countermeasure of Floor Heave of Soft Sock Roadway with Large Section

针对大断面软岩巷道在开挖支护后所表现出的底鼓现象,对其耦合控制对策进行了数值模拟及工程应用研究。对大断面软岩巷道底鼓变形机理研究表明,大断面软岩巷道底角是支护的关键部位;巷道是一个有机整体,单一的支护效果并不明显,必须进行全断面支护。基于上述研究,提出底鼓耦合控制对策,即在锚网索耦合支护的基础上,利用底角注浆锚杆对关键部位进行加强支护,从而达到控制巷道底鼓变形的目的。数值模拟与工程应用结果表明,采用底鼓耦合支护形式,可以有效地控制围岩底鼓变形,巷道围岩稳定性大大提高。研究结果对于大断面软岩巷道底鼓控制具有一定的指导意义。

The failure mechanism and coupling control countermeasure of floor heave of soft rock roadway within large section after excavating and supporting were investigated by numerical simulations. Some typical cases of engineering applications were also analyzed. The study on the floor heave＇s mechanism of soft rock roadway with large section indicated that the bottom comers of roadway were the key position for supporting. For the roadway as an organic whole, a haploid supporting was not of distinct supporting effect, it should be supported on whole section. For controlling floor heave deformation, a coupling control countermeasure was put forward based on the research result, that meant the key positions of surrounding rock should be reinforced at the bottom comers of roadway by anchor bolt - grouting after bolt - net -anchor coupling support. The results of numerical simulation and engineering applications showed that the coupling support for floor heave can effectively control the floor heave deformation of roadway and definitely enhance the stability of surrounding rock of roadway.