Experiment Study on Secondary Grouting Reinforcement of Broken Surrounding Rock in Large Loose Circle

In order to solve the continued deformation problem of the gateway with broken surrounding rock under the high geostress conditions in Zhaozhuang Min e,a study was conducted on the secondary grouting reinforcement with the theoretical analysis,test simulation and site observation means.Based on the loose circle the ory,the geological radar detection technology,the in-situ re-grouting technology with shallow borehole and the bolt and grouting reinforcement technology were applied t 0 the full section secondary grouting reinforcement test based on the previous bolt/steel mesh/anchor support of the south air returning gateway in the west wing of the mine. The numerical software similar simulation and the gateway deformation observation were applied to the inspection of the support effect.The results showed that th e secondary grouting reinforcement had improved the integrated strength of the surrounding rock,high reduced the plastic zone,formed a complex loading structure,rele ased the joint loading and self loading of the anchoring mass and the broken surrounding rock and could effectively solve the continued deformation problem of the brok en surrounding rock.