Model Experimental Study on the Safety Characteristics of Surrounding Rock Support in Deep Wells

Regarding the issue of shaft support for the auxiliary shaft of the Xianshan Iron Mine at a depth of 900-1000m in high-stress strata, based on the similarity theory, a new type of mold was developed by using the physical similarity model test method, and the experimental model of shaft lining and surrounding rock was poured. Based on this, two sets of large-scale destructive tests of shaft lining and surrounding rock were carried out. The deformation and failure law of shaft lining and surrounding rock under high ground stress and the corresponding horizontal ultimate bearing capacity characteristics were studied, and the safety support characteristics of shaft lining under the interaction of shaft lining and surrounding rock were obtained. The experimental study shows that the axial pressure on the shaft wall directly affects the horizontal ultimate bearing capacity. In the design of the shaft wall, the influence of the axial pressure on the concrete stress state should be considered, and the vertical pressure should be modified to optimize the utilization of the three-dimensional compressive strength of the concrete. The reliability of the 400 mm C30 concrete shaft wall at a depth of 1,000 m in the actual project is verified, and the horizontal ultimate bearing capacity of the shaft wall at a depth of 1000 m is obtained.