岩体的非连续变形分析前处理部分2（区别与DC部分）：主要是用于判断裂隙是否形成封闭回路，利用tree cutting方法去除无效裂隙得到块体网络，为下面的计算做准备。-Rock mass deformation analysis of non-continuous pre-treatment part 2 (the difference with the DC part): The principal objective is to determine whether the formation of fissures closed loop, the use of tree cutting to remove the invalid block has been fractured network to prepare for the following calculation.