According to the mountainous shallow-buried coal seam mining engineering geological conditions in Guizhou Fa'er coal mine, it researched the slope breaking and displacement characteristics when mountainous shallow-buried coal seam mined with similar material simulation method. The results showed that:
based on the slope movement characteristics, the mountainous coal seam overlying strata could be divided into two regions – "breaking movement area" and "common movement area". "Breaking movement area" belonged to shallow-buried coal seam and "common shift area" belonged to common depth coal seam.
When mountainous shallow-buried coal seam mined, its overlying strata could turned to be "multilateral structure". They were relative to slope morphology and tensile cracks. Its movement characteristics were dumping to the goaf behind the working face, and then slide along the fracture surface. Its trajectory was "S" type.
When mountainous coal seam mined, overlying strata would produce lateral displacement with direction to the free surface.
In western China there were abundant coal resources, and a large proportion of them were buried shallow, with the depth less than 100 m. Huang (2000), Zhang, Zhai and Wang (2010) and Fan, Liu, Xiao and Zheng (2010) indicated that shallow-buried coal seam could be divided into two categories. One was mainly distributed in the northern part of Shanxi, the southwest of Neimenggu and the east part of Ningxia desert area, with relatively flat surface's terrain, thick loose sand and thin bedrock. The other was mainly distributed in the southwest of China, such as Guizhou, Sichuan, Chongqing and Yunnan. Their corresponding surface's terrain was mountainous region, part of the coal seam outcrop buried shallowly, the unconsolidated loading was thin and bedrock thickness changes greatly.
In China, the research and exploration about shallow-buried coal seam's strata behavior and strata control began in early 1990s. These researches were mainly focused on the law and the structural characteristics and roof breaking, the rules of the working face's strata behavior and the supports' working resistance in the workface with thick loose sand and thin bedrock at the region of Shendong mine district. But there was less research on the influence of mountainous surface's terrain on shallow-buried coal seam mining (see e.g. Huang (2000), Song, Gu and Yan (2007),Yin (2007), Wang, Wang, Wang and Chen (2006), Li, Ye and Zhang (2000), Li and Chen (2004), Hou (2003), Zhao (2003), Liu and Gao (2005),Walker (1998), Kang (2008) and Dai, Zhai and Hu (2007)). Kang (2008), Dai, Zhai and Hu (2007), Guo, and Liu and Zhang (2008) indicated that on account of the lack of monitoring data on the existing researches about deformation and fracture of mountainous shallowburied slope, therewas no comprehensive understanding of the movement characteristics of mining slop and the effects of slope movement on mining, so it was hard to guide the roof rock practices and it brings huge risk to safety production.
