The mine flooding happed during construction of the air shaft in Qidong Coal Mine. 祁东煤矿风井在建井过程中,发生钻井井壁突水事故,井筒被淹。
Based on the test results, the design method of vertical bearing capacity of the retractable drilling shaft lining was obtained. 由此提出了可缩性钻井井壁竖向承载力的设计方法。