龙口北皂矿海域下H2106综放面井下导高观测

水体下采煤需要观测采场覆岩导水裂缝带高度(简称导高)。龙口北皂矿海域H2106综放面地表为海水,为了解决地表海水区难以施工导高观测钻孔的技术难题,在井下采用仰斜钻孔与井下导高观测仪进行了导高观测,该方法钻孔工程量小且观测精度高。在H2106综放面共设置3个观测剖面,施工了4个采前对比观测钻孔和8个采后导高观测钻孔,并利用顶板覆岩中泥灰岩含水层开采前后其含水量的变化判断导水裂缝带上限。实测得出H2106综放面导高值为38.8m,导高与采厚比为9.5。对于龙口矿区软弱岩层,导高观测的最佳时段为采后10~20d。

Observation of height of excavating face H2106 in Longkoubeizao mine under sea

Mining under water needs to observe height of water-flowing fractured zone, to determine a reasonable upper mining limit. The surface of excavating face H2106 in Longkoubeizao mine is sea. To solve the technical problems in drilling holes for observing height of the water-flowing fractured zone, the height of the water-flowing fractured zone was obseved by using upward holes and detector for observing height of the water-flowing fractured zone. This method requires small amount of drilling works and has high observation accuracy. In excavating face H2106 three observation section were set, 4 pre-mining holes and 8 after-mining holes were drilled for observing height of the water-flowing fractured zone,and the upper limit of water flowing fractured zone was determinated by using the water content change of marl aquifer in the roof before and after mining . By observing,the height of water flowing fractured zone of excavating face H2106 was 38.8 m, the ratio of height of the water-flowing fractured zone and mining thickness was 9.5.