The support of coal roadways is seriously affected by intense dynamic pressures.This can lead to problems with large def......

2004年3月中旬,某商品住宅小区一幢住宅6层屋面现浇混凝土施工中发生坍塌事故,坍塌物将与之垂直对应的下面6层预应力空心板全部砸......

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