Abstract: As large flood discharge flow and high water head of Dagangshan hydropower station, energy dissipation is one of the key technical issues of the project. Based on the prototype observation results of fluidity, discharge capacity, hydrodynamic pressure and velocity in flood discharge by deep hole, combined with operation condition, the hydraulic characteristics of the plunge pool are analyzed. As well, the operation safety of the deep hole and plunge pool are demonstrated. Moreover, some suggestions for rational operation and further research are put forward.

Key words: dam deep hole, plunge pool, hydraulics, prototype observation test, hydrodynamic pressure

摘要： 大岗山水电站拱坝坝身泄洪流量大、水头高，泄洪消能是工程的关键技术难题之一。基于深孔泄洪时流态、泄流能力、水垫塘内动水压力及流速水力学原型观测成果、工程实际运行效果，对水垫塘的水力特性进行分析，论证了当前深孔及水垫塘泄洪运行的安全性，并对工程的合理化运行、下一步研究提出了建议。

关键词: 深孔, 水垫塘, 水力学, 原型观测, 动水压力