downpipe

noun

1. （从房顶到地面排水的）雨水管
   a pipe for carrying water from a roof down to the ground or to a drain

1. The downpipe of this building could fall off at any time.
   这个楼的落水管随时都有脱落的危险。
2. The paper thoroughly analyses the method to determine the catchment area, delaying coefficient and convergent time for the outdoor downpipe design of the high-rise building through an example of the division diagram of its outdoor rainwater catchment area.
   以高层建筑室外雨水汇水面积划分图为例，详细分析了高层建筑室外雨水系统设计中汇水面积，延缓系数以及地面集水时间的确定方法。
3. Liner of feed downpipe in limestone transportation line should be high abrasion-proof liner, etc.
   石灰石输送线上的下料溜子内衬应尽量选择高耐磨性内衬等。