In the mountain tunnel construction, the secondary lining concrete crack is a certain universal quality problem.

在山岭隧道施工中，二次衬砌混凝土裂缝成为带有一定普遍性的质量问题。

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In the mountain tunnel construction, the secondary lining concrete crack is a certain universal quality problem.

在山岭隧道施工中，二次衬砌混凝土裂缝成为带有一定普遍性的质量问题。

youdao