There are four layer coal in Huafeng coal mine of Xinwen coal group company, it is mined layer by layer, artificialroof is used by diamond metal net over a long period of time.
新汶矿业集团华丰煤矿四层煤分层开采，长期以来全部采用金属菱形网作假顶。
2
The settlement calculation of artificialroof was done with structural mechanics analysis method, and the scale of thickness which can maintain the artificialroof stably was obtained.
首先通过结构力学解析法对顶板沉降量的计算，估算出能维持顶板稳定的厚度取值范围；
3
Through the detail introduction on optimization of raining method in Shandong Wangcun Bauxite Mine, this paper puts forward a new mining method——longwall caving with artificialroof pillar.