Distribution Law of Deep Complex In Situ Stress and Influence of Underground Engineering in Huanghuai Area

Abstract

Huanghuai area is rich in coal resources, but due to the increasingly complex geological environment faced by coal mining, the complexity of structural stress is one of the main problems. In order to find out the distribution law of deep in situ stress in the Huanghuai area, the in situ stress measurement data of 81 effective measuring points in 24 mines with depths ranging from −100 m to −1200 m are analyzed in the present study base on the in situ stress measurement data. Furthermore, numerical simulation and field observation are used to analyze the deformation and failure characteristics of the surrounding rock. The research results show that the deep mining area of Huanghuai exhibited a high stress level, and the vertical and horizontal principal stress increases with increasing depth. The ratio of the lateral pressure coefficient ranges from 0.90 to 2.70, and the in situ stress field presented a trend of transition to the quasihydrostatic pressure field type as the depth extended, in which 80.23% of the measuring points are distributed between 1.20 and 2.10, belonging to the typical tectonic stress field type in which tectonic stress is absolutely dominant. The observation results of the surrounding rock and numerical simulation reveal that when the layout axis of the roadway is approximately perpendicular to the direction of the maximum horizontal principal stress, a high stress concentration area is present on the roof and floor of the roadway, the deformation increases sharply, and the support pressure of the roof and floor increases.