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

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 corners 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 corners 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.