Support Technique of Horse Head in Weakly Cemented Soft Rock

Abstract

Part of the chambers of the coalmine roadway in Western Inner Mongolia and Eastern Ningxia of China are in weakly consolidated soft rock formation. Taking the horse head engineering in Maiduoshan coal mine in the main level as an example, a new scheme was put forward to optimize the original supporting scheme. A three-dimensional numerical model of the project of horse head was set up. According to the rock composition, different layer has different material properties. Initial stress of the model was given according to the measure results of in-situ stress. Strain softening constitutive model was used in calculation. The mechanical softening of surrounding rock after excavation was studied by numerical analysis method. Numerical analysis was done before construction, and displacement of horse head surface was monitored in construction. The result of numerical analysis and the monitoring data are similar. Good effect has been achieved after the implementation of the project.