坚硬顶板预裂弱化后应力场及裂隙场演化特征数值模拟研究

Numerical Simulation Study on the Evolution Characteristics of Stress Field and Fissure Field After Presplitting and Weakening of Hard Roof

工作面上覆坚硬顶板,开采过程不易垮落,采场周围形成高应力场,易引发冲击地压与瓦斯异常涌出灾害事故。为确保安全生产,工作面回采过程中,需对坚硬顶板进行弱化处理,弱化后煤、岩层应力场、裂隙场演化特征是工作面灾害治理的依据和关键,通过理论分析获得顶板的初次来压步距和坚硬顶板分类,以宽沟煤矿I010202工作面为工程背景,利用UDEC数值模拟软件,结合矿井实际地质资料及相关煤岩力学参数,建立平面数值模型,对工作面开采过程中应力场及裂隙场演化特征进行模拟。模拟计算得出顶板弱化后应力场、裂隙场分布特征,为工作面冲击地压及瓦斯灾害治理提供了理论依据。

The overlying hard roof of the working face is not easy to collapse during the mining process.A high stress field is formed around the stope,which can easily cause disaster accidents such as rock burst and gas abnormal outburst.To ensure safe production,during the stoping process of the working face,it is necessary to conduct weaken treatment on the hard roof.The evolution characteristics of the stress field and fissure field of the coal and rock layers after weakening are the basis and key to the disaster governance of the working face.The initial pressure step distance of the roof and the classification of the hard roof are obtained through theoretical analysis.Taking the I010202 working face of Kuangou Coal Mine as the engineering background,UDEC numerical simulation software is used,combined with the actual geological data and relevant coal rock mechanics parameters of the mine,to establish a plane numerical model and simulate the evolution characteristics of the stress field and fissure field during the mining process of the working face.The simulation calculation obtains the distribution characteristics of the stress field and fissure field after the weakening of the roof,providing a theoretical basis for the governance of rock burst and gas disasters in the working face.