隔河岩工程水力学安全监测技术及成果分析

Analyses on safety monitoring results in hydraulics aspect for Geheyan Project

1998年汛期隔河岩水利枢纽观测部位为深孔、表孔及消能工。其观测内容包括流态、时均压力、空化噪声、流速、雾雨。观测结果表明 :该工程泄洪表孔、深孔、消力池及辅助消能工的各项水力学特性基本良好。泄水建筑物过流面、一级池两边岸坡均无蚀损 ,二级消能工上的消力墩、差动坎等均基本完好无损 ,但 1 998年 2月抽干检查发现消力池有局部磨损 ,左岸隔流堤护岸在 1 998年泄洪过程中发生局部坍滑。由于集中坝身泄洪 ,泄洪时雾化现象较严重 ,故须采取措施 ,以确保工程安全运行。将部分原型观测资料与模型试验资料和计算值作了对比 。

Monitoring observation localization for Geheyan Project in 1998 flood season was the deep outlets,the surface spillway,the still basin and auxiliary energy dissipators.The observation content included the flow pattern,time average pressures ,flow velocities,fog rain and inspection in situ.The monitoring results indicated that the hydraulic properties of every item of the spillway,deep outlets,stilling basin and auxiliary energy dispersion are overall good;on the flow boundaries of flood releasing structures no cavitation erosion occurred;the two side slopes of stilling basin stage 1,the energy dissipation baffles and differential sills on the stilling basin stage 2 were elementarily perfect.But it is found from an inspection after dewatering in February,1998,that there was partial wear in the stilling basin,and partial collapse at the protection bank of dividing dike of left bank produced in the releasing flood process of 1998.In virtue of releasing flood by using ski jump type structure,fog phenomenon is more serious ,therefor appropriate meaures must be adopted to secure safety operation.Through comparison of data observed in prototype ,measured on model and obtained by computation,some basical agreements in general trend and among corresponding values therefrom are achieved.