一、概述船闸和升船机是在运河或天然通航河流上,用以克服水位集中落差的两种主要过船建筑物。由于水运运价比较便宜,如在美国水运费用仅为铁路运输的三分之一至四分之一,因而近年来欧美资本主义各国为了发展它的资本丰义经济,获取更大利润,与它的海外掠夺政策相配合,除了新建扩建沿海港口,加大码头及航道水深外,并积极发展内陆水 I. Overview Locks and shiplift are two main types of over-ship structures used to overcome the concentrated drop in water level on canals or natural sailing rivers. As water transport is cheaper, as in the United States, the cost of transporting water is only one third to one quarter of that of rail transport. Therefore, in recent years, the capitalist countries in Europe and the United States have made greater profits in order to develop their capitalist economy, In addition to the new expansion of coastal ports, increasing the water depth of docks and waterways, and actively developing inland water