以往修筑了很多混凝土非过水沙防坝，有效地阻止了泥沙流向下游，致使在短时期内泥沙在库区沉积。２０ａ前就已修筑了有一定间隔的钢结构过水型大坝。平时或中小型洪水来临时，可阻止泥沙沉积在水库上游，以确保水库的库容量，当出现泥石流时，可以阻挡先期到达的大块石，并可 In the past, many concrete non-over-water and sand-dam were built, which effectively prevented sediment from flowing downstream, resulting in sediment deposition in the reservoir area in a short period of time. 20a has been built before a certain interval of the steel structure of the water dam. In normal times or when small and medium-sized floods come, sediment deposition can be prevented upstream from reservoirs to ensure the reservoir capacity. When debris flow occurs, it can stop the pre-arrival large stones and can