At the same time, the dividing line of shallow tunnel and depth tunnel in frozen earth is discussed initially.

同时，对冻土隧道的深浅埋分界进行了初步探讨。

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At the same time, the dividing line of shallow tunnel and depth tunnel in frozen earth is discussed initially.

同时，对冻土隧道的深浅埋分界进行了初步探讨。

youdao