railroad tie

1. The British call a railroad tie a sleeper.
   铁路枕木为什么是黑色的。
2. For a long time, some concrete structures usually can not be used because of lacking resistance of impact, such as different kinds of silo structure, pavement concrete, deck concrete, railroad tie, shaft, ore drop shaft as well as national defence establishment.
   长期以来，在各种筒仓结构、路面混凝土、桥面混凝土、铁路枕木、矿石溜井以及国防设施等频繁承受动力荷载的结构中，混凝土通常是由于抗冲击性能的不足而丧失其使用性能。

noun

1. one of the cross braces that support the rails on a railway track
   1. the British call a railroad tie a sleeper

   Synonym:    tiecrosstiesleeper