泄水建筑物在施工和运行期间,其混凝土过水面经常受到水流中砂石的长期冲磨而发生破坏,尤以大粒径推移质卵碎石的冲击磨损破坏最为严重.1973年美国德沃夏克坝(Dworshark Dam)的溢洪道,运行16个月,消力池就遭受到严重的破坏,以至出现了深达3米的冲蚀点,大约1500立米混凝土和基岩被冲蚀.究其原因,主要是池内聚集在水底的卵碎石,钢筋和其它杂物冲磨所致.美国陆军工程师水道试验站(U.S.Army Engineer Water- During the construction and operation of the drainage structures, the concrete over water surface is often damaged by the long-term sand blasting in the water current, After 16 months of operation, the spillway of Dworshark Dam was severely damaged, causing an erosion point as deep as 3 meters and about 1500 meters of concrete and bedrock to be eroded The reason is mainly due to the accumulation of eggs in the bottom of the omelette, steel bars and other debris due to the US Army Engineer Water Test Station (USArmy Engineer Water-