Research on floor heave treatment of steel pipe concrete column in deep bottom drainage roadway in Chiyu Mine

Abstract

Aiming at the serious problem of floor heave of the high-stress deep roadway, take 4# bottom-draining roadway in the north wing of the first mining area of Chiyu Coal Mine as an example, the law of non-linear large deformation of the floor of the roadway under high stress is studied, the mechanism of the crushing failure of the surrounding rock of the roadway floor is analyzed, and the floor heave treatment technology of the roadway floor steel tube concrete column is proposed. Through the method of numerical simulation, the influence of different supporting lengths, angles and row spacings of the concrete-filled steel tube columns on the floor heave of the roadway is analyzed. The test results show that: high stress field, low rock strength, water softening of the surrounding rock of the floor, and defects in the original supporting structure are the main reasons for the strong floor heave of the roadway; the concrete-filled steel tube column has the characteristics of high strength, high rigidity and good shear resistance, which can effectively enhance the supporting strength of the surrounding rock of the floor and restrain the compression deformation of the surrounding rock; when two concrete-filled steel tube columns are arranged in each row of the floor, the supporting length is 6 m, the inclination angle is 30°, and the row spacing is 1.2 m, the deformation of the roadway floor is stable at a small value. Field tests have verified that the bottom heave treatment technology of concrete-filled steel tube columns can effectively control this type of bottom heave.

Keywords

• deep roadway
• extruding fluidity floor heave
• concrete-filled steel tube column
• heave control
• numerical simulation