There are three coal mines in Xin'an Coalfield. The Shanxi group irregular(2-1) coal seam has softroof, soft coal and soft floor.
在新安煤田新建的三对矿井，主采煤层均为山西组2-1三软不稳定煤层。
2
This paper puts forward support plan through analyzing strata behavior regularity of coal roadway in seam with softroof, soft coal and soft floor.
文章通过对永华煤矿“三软煤层”煤巷矿压规律进行分析，提出了支护方案。
3
Softroof and floor of coal seam could be easily damaged while support was not timely and strength was not enough, so overall support was needed for laneway with strong support strength.