Research on mechanism of floor heave occurrence and its control technology in thick coal seam comprehensive gob-side entry retaining
HU Xiaohan
LIU Shangming
XIE Xiaoguang
SUN Yanqing
LIU Senhu
Abstract：To address the problem of floor heave often occurs in the gob-side entry retaining of fully-mechanized caving in thick coal seams,this paper took the N2301 roadway of Gucheng Coal Mine as the engineering background and used a combination of field re-search,theoretical analysis and numerical simulation to study the mechanism of the occurrence of floor heave and its control technology.Field investigation found that the roadway exhibited obvious characteristics of squeeze flow and floor heave.A deep high stress roadway floor heave mechanical model was constructed,and the mechanism of floor heave occurrence was analyzed in combination with theory.The results showed that the higher the degree of stress concentration in the roadway,the greater the depth of damage to the roadway floor.According to the field situation,the method of grouting reinforcement was proposed to control the floor heave,and COMSOL numer-ical simulation software was used to study the range of bottom slurry pressure distribution under different grouting parameters,and the grouting pressure of 3 MPa,grouting time of 6 min and the row distance between anchor cables of 1000mm × 1000mm were determined for N2301 roadway.Engineering applications showed that the maximum floor heave of the roadway was 15 mm,and the maximum separa-tion value at a depth of 6 m in the surrounding rock was 23 mm.The optimized grouting parameters were applied in the advance support-ing of N2301 roadway in Gucheng Coal Mine,and good engineering results were achieved,and the research results have important refer-ence value for the management of bottom drum and design of grouting parameters in similar conditions.
Keywords：floor heavegob-side entry retainingthick coal seamgrouting reinforcementCOMSOL numerical simulation
Publication Date：2024-06-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 41-48 )