中文摘要：

本文针对国内首次遇到的新坝施工期受到老坝度汛下泄高速水流的冲击问题,开展了试验研究。在总结国内外冲蚀研究进展的基础上,研制了新坝高速水流冲击切片试验装置,采用四个冲击速度对四种龄期的筑坝碾压混凝土进行了近百组冲蚀试验,总结得出不同龄期混凝土的冲蚀参数和冲蚀规律,通过乘幂拟合得到筑坝碾压混凝土冲蚀率的速度指数在3～4之间。试验成果对工程施工期的安全度汛有着实际的技术支撑作用。

英文摘要：

Impact to a new dam under construction by high-speed flow discharged by the old dam is a new phenomena that is encountered for the first time in China. To study this problem, a systemic test was conducted in this work. Based on previous studies in the literature, a section test device of scale 1 ： 1 was developed and nearly 100 erosion tests were completed for four concrete ages and four different jet speeds. Analysis of the measurements reveals the erosion laws and key parameters of the roller compacted concrete of different ages, and by power fitting it shows that the velocity index of erosion rate is in the range from 3 to 4. The results would provide a practical technical guide for safety design of dam construction in flood season.