<bdo id="2ffcv"><rt id="2ffcv"></rt></bdo><rt id="2ffcv"><rt id="2ffcv"></rt></rt><rt id="2ffcv"></rt><delect id="2ffcv"><delect id="2ffcv"><bdo id="2ffcv"></bdo></delect></delect><noframes id="2ffcv"><rt id="2ffcv"></rt><bdo id="2ffcv"><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"></rt><bdo id="2ffcv"></bdo><noframes id="2ffcv"><rt id="2ffcv"></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><rt id="2ffcv"><rt id="2ffcv"></rt></rt><rt id="2ffcv"></rt> <noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><rt id="2ffcv"></rt><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"> <rt id="2ffcv"><rt id="2ffcv"></rt></rt><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"></rt><rt id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt></rt><noframes id="2ffcv"><rt id="2ffcv"></rt><noframes id="2ffcv"><noframes id="2ffcv">
您好!歡迎來到煤礦安全生產網!

開鑿立井時,井口與堅硬巖層之間的井巷必須用混凝土砌(澆)筑,并向堅硬巖層內至少延深10m以上。 (判斷題)

作者:煤礦安全網 2022-05-27 08:40 來源:煤礦安全網 立井 井口 巖層 井巷 混凝土
題目信息:

  開鑿立井時,井口與堅硬巖層之間的井巷必須用混凝土砌(澆)筑,并向堅硬巖層內至少延深10m以上。 (判斷題)

答案

煤礦安全網(http://www.nanibalconysafetynets.com)

備案號:蘇ICP備12034812號-2

公安備案號:32031102000832

Powered By 煤礦安全生產網 徐州鑄安礦山安全科技有限公司

使用手機軟件掃描微信二維碼

關注我們可獲取更多熱點資訊

感謝網狐天下友情技術支持

国产亚洲校园有声小说|亚欧偷拍电影图片小说一区|一级做a爰片久久毛片潮喷妓|欧美色精品视频|欧美日韩一级黄色片
<bdo id="2ffcv"><rt id="2ffcv"></rt></bdo><rt id="2ffcv"><rt id="2ffcv"></rt></rt><rt id="2ffcv"></rt><delect id="2ffcv"><delect id="2ffcv"><bdo id="2ffcv"></bdo></delect></delect><noframes id="2ffcv"><rt id="2ffcv"></rt><bdo id="2ffcv"><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"></rt><bdo id="2ffcv"></bdo><noframes id="2ffcv"><rt id="2ffcv"></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><rt id="2ffcv"><rt id="2ffcv"></rt></rt><rt id="2ffcv"></rt> <noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><rt id="2ffcv"></rt><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt><noframes id="2ffcv"> <rt id="2ffcv"><rt id="2ffcv"></rt></rt><noframes id="2ffcv"><noframes id="2ffcv"><rt id="2ffcv"></rt><rt id="2ffcv"><rt id="2ffcv"><delect id="2ffcv"></delect></rt></rt><noframes id="2ffcv"><rt id="2ffcv"></rt><noframes id="2ffcv"><noframes id="2ffcv">