They propped the old tunnel up with new timbers.

他们用新的木梁支撑旧坑道。

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The enlarging or reconstruction requirement of existing tunnel, which can be divided into increases based on traffic flow, new ventilation or escape space, old tunnel reinforcement and so on.

既有隧道的扩挖或改建需求，大致可分为基于交通量增加、新增通风或逃生空间、老旧隧道维修补强等。

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On March 28, 2010, miners digging a new tunnel accidentally cracked an old one filled with water. The ensuing2 flood trapped 153 workers underground.

2010年3月28日，矿工们在开挖一条新矿道时，不慎将一条注满水的旧矿道凿穿，喷涌而出的水随即将153名矿工困在了地下。

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Until then, the No. 1 train will roll through the century-old tunnel as it loops around its last, lower Manhattan stop before heading uptown again.

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The standoff ended when French troops escorted rebels into Mr. Gbagbo's presidential palace, where he had been hiding in an old tunnel that connects the palace to France's embassy.

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So commuters are riding on a mix of old and newer trains that share a tunnel under the Hudson running on two tracks built as recently as 1910.

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