某重力坝工程泄洪排沙底孔的运行方式研究  

Study on the operation mode of the bottom orifices for the discharge of flood and sediments in a gravity dam project

作　　者：王京 孙双科[2] 汪星 孟席 柳海涛[2] 乔明秋[1] WANG Jing;SUN Shuangke;WANG Xing;MENG Xi;LIU Haitao;QIAO Mingqiu(PowerChina Beijing Engineering Corporation LTD,Beijing 100024,China;China Institute of Water Resources and Hydropower Research,Beijing 100038,China;Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]中国电建集团北京勘测设计研究院有限公司,北京100024 [2]中国水利水电科学研究院,北京100038 [3]安徽理工大学,安徽淮南232001

出　　处：《中国水利水电科学研究院学报》2020年第6期455-461,共7页Journal of China Institute of Water Resources and Hydropower Research

摘　　要：某重力坝工程最大坝高67 m,其泄水建筑物由4个溢流表孔与2个泄洪排沙底孔组成,采用底流消能方式,因水库泥沙问题较为突出,设计方面制订了优先开启底孔进行泄洪排沙的运行方式。整体水工模型试验发现,当宣泄中小洪水底孔全开运行时,由于入池Fr数小,且下游水位低,导致底孔消力池消能效果欠佳,护坦下游河床冲刷严重,为此对泄水建筑物的运行方式进行了调整,采用底孔闸门半开运行并启用表孔参与泄洪的运行方式。水工模型试验结果表明,泄洪底孔采用半开方式能显著提高消力池消能效果并减轻下游冲刷,是适合于本工程的泄洪排沙运行方式。The structures to discharge flood and sediments for a gravity dam with the maximum height of 67 m consist of 4 overflow surface outlets and 2 bottom orifices,in which hydraulic jump is used for energy dissipation.Due to the prominent problem caused by sediments in the reservoir,the priority operation to discharge flood and sediments is proposed by using the bottom orifices in the design.It is found that the energy dissipation in the stilling basin for the small and medium flood by fully opening the bottom orifices is insufficient due to low Fr in the pool as well as the low downstream water level in the full-scale physical model tests.This also results in serious scouring for the downstream river bed apron.Hence,the operation mode for the discharge structures is adjusted in such a way that the bottom orifices are half opened and surface outlet overflow is adopted.Further measurements in the full-scale physical model indicate that the energy dissipation in the stilling basin is significantly improved and the scouring to the downstream river bed is eliminated,which suggests that the adjusted operation model can be applied to discharging the flood and sediments in the project.This study of the operation mode for the discharge structures can provide a reference for similar projects.

关 键 词：泄洪排沙底孔 底流消力池 水力设计 运行方式 下游冲刷 

分 类 号：TV653[水利工程—水利水电工程]