1) coal-mining under three circumstances
三下采煤理论
2) "three unders" mining
"三下"采煤
1.
Yungang Mine is typical “three unders” mining district in which there is a big area together with water, railway and buildings.
云冈矿“三下”压煤面积大,且建筑物、水体、铁路连成一体,为典型的“三下”采煤。
3) sanxia caimei
三下采煤
4) min-ing under buildings
"三下一上"采煤
5) Three Underlying Belts"Theory
"下三带"理论
1.
Probe into the Mining of the Coal Bed Bearing the Threat of Pressed Water with “Three Underlying Belts”Theory;
以“下三带”理论对开采受承压水威胁煤层的探讨
6) mining of seams in conditions of"three unders-one above"
"三下一上"压煤开采
补充资料：三下采煤
建筑物下采煤、铁路下采煤、水体下采煤的总称。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。
参考词条