The Characteristic Of Pressure-relief Roadway Support With Foam Concrete Flexible Layer In Pressure-relief Gap

As an important research direction of the roadway, Pressure-relief support is amethod which could make full use of potential stability of surrounding rock itself.Relief gap is suitable for soft rock roadway support because of allowing surroundingrock deformation. Foam concrete is a new material with many new features likeability absorbing deformation. Filling the relief gap with foam concrete as FlexibleLayer can provide new ideas and methods for roadway support.This research analyzed the mechanism of pressure-relief support with foamconcrete. The stability of roadway which adopted the foam concrete fillingpressure-relief gaps were analyzed by using ABAQUS simulation software. And thisthesis analyzed the roadway stability in the soft rock seam floor under the influenceof mining moves. Related work and conclusions are summarized as follows.Through the analysis of the roadway support principle and the impact of theplastic zone on roadway supporting structure, it is concluded the theoretical Basis offoam concrete can improve the effect of pressure relief and summarized the feasibilityof foam concrete used for the pressure-relief support.The research established five roadway simulation models. The first one was aroadway did not have a pressure-relief gap. The second one was a roadway had apressure-relief gap without any medium. The third one was a roadway had apressure-relief gap with100mm foam concrete filling into pressure-relief gap. Thefourth one was a roadway had a pressure-relief gap with200mm foam concrete fillinginto pressure-relief gap. The fifth one was a roadway had a pressure-relief gap with100mm common concrete filling into pressure-relief gap. By analyzing the stability ofthese five roadway simulation model established under the same conditions byABAQUS, The study found that the roadway with foam concrete filling into thepressure-relief gap could provide some space for deformation of surrounding rock. Sothat the surrounding rock could produce certain plastic zone, releasing plastic rockperformance energy, making full use of potential stability of surrounding rock itself.Meanwhile, the deformed layer of foam concrete could be coordinated with thesurrounding rock deformation together.After excavating the sublevel in the bottom, which is the sublevel near soft seam floor, mining moves greatly impacted on the stability of the roadway. The impactmainly embodied in the uplift of soft seam floor to the stope in high ground stress.This phenomenon leaded to the settlement of the soft rock area outside the stopeincrease in the vertical direction, while the horizontal displacement increases. Andthere is a trend to move stope. This effect on the surrounding rock of the roadway wasnon-symmetrical.