岸边泄洪洞最大泄量的估算方法

大型水电站泄洪洞单洞泄洪规模是关乎枢纽布置、泄洪安全、以及工程投资的重要技术指标，以往未见量化研究报导。本文从计算泄洪洞挑流水舌挑距与下游河道冲刷深度出发，建立了泄洪洞泄量与下游河道宽度、泄洪洞布置轴线与下游河道夹角、基岩抗冲能力以及泄洪洞运行方式等指标之间的量化关系，对白鹤滩、小湾、溪洛渡、锦屏一级泄洪洞分别进行了定量估算研究，所得结果与工程实际以及相应的设计方案基本一致，表明该估算方法具有较高的可靠性，可用以估算待建工程泄洪洞最大泄量或对已建工程泄洪洞泄洪规模的合理性进行评价。

Estimation of the maximum discharge for bank spillway tunnel

The discharge for a single spillway tunnel in a large hydropower station is an important design parameter for the dam layout, spillway safety, and project investments.However, quantitative investigation of the maximum discharge was limited in previous studies.Based on the calculation of the tunnel discharge jet trajectory length and downstream scour depth, this study established relationships between tunnel discharge and downstream width, tunnel layout axis and downstream river channel width, bedrock scour resistance, tunnel operation mode, etc.Quantitative estimation studies have been conducted on the spillway tunnels respectively for the projects of Baihetan, Xiaowan, Xiluodu, and Jinping-I.The estimation results are well consistent with the engineering practice and the design schemes, indicating high reliability for the estimation method.This method can be applied to predict the maximum discharge for construction-scheduling spillway tunnels and to assess existing spillway tunnels in terms of the maximum flow discharge.