摘要
珠三角网河地区河流属感潮河段,堤防上建有按前、后二级挡水设计的水闸,部分二级挡水的前、后闸还承担分洪任务,在外江发生较大洪水而内河遭遇低潮位需要分洪时,如何调控前、后闸运行时的水位~流量关系,确保水闸建筑物在分洪期间的安全十分重要。以沙口水利枢纽的分洪闸(前闸)、引水闸(后闸)为例,根据闸基地质情况确定允许渗透比降,计算前闸分洪运行时允许的最大水头差,分析分洪时上下游水位可能出现的不利组合,考虑后闸不具备调节开度的实际情况,计算得出对应不同水位组合分洪时前闸的开度-流量关系曲线,并提出感潮河段前、后二级挡水闸分洪工况安全调度的3个原则:前闸必须调节开度控制流量,后闸二级挡水保证前闸的渗流安全;由闸基允许渗透比降反算得出前、后闸分洪运行时的上下游水头差;分洪闸闸门型式优先采用弧形闸门并配实时开度监控。
The rivers in the Pearl River Delta network river area are tidal reach sections.Some embankments are equipped with water gates designed for two-stage water blocking,and some of the front and rear gates of the two-stage water blocking also undertake flood diversion tasks.When a major flood occurs in the outer river and the inner river encounters a low tide level and requires flood diversion,how to control the water level-flow relationship during the operation of the front and rear gates to ensure the safety of the water gate structures during the flood diversion period is important.Taking the flood diversion gate(front gate)and the water intake gate(rear gate)of the Shakou Water Conservancy Hub as an example,the allowable seepage gradient is determined based on the geological conditions of the gate foundation,the maximum allowable water head difference during the flood diversion operation of the front gate is calculated,the unfavorable combinations of upstream and downstream water levels that may occur during the flood diversion are analyzed,and considering the actual situation that the rear gate does not have the ability to adjust the opening degree,the opening degree-flow relationship curves of the front gate during the flood diversion for different water level combinations are calculated.Three principles for the safe operation of the two-stage water blocking gates in tidal reach sections during flood diversion are proposed:The front gate must adjust the opening degree to control the flow,and the rear gate’s two-stage water blocking ensures the seepage safety of the front gate;The upstream and downstream water head differences during the flood diversion operation of the front and rear gates are calculated based on the allowable seepage gradient of the gate foundation;The gate type of the flood diversion gate should preferentially adopt the arc gate and be equipped with real-time opening degree monitoring.
作者
周荣福
Zhou Rongfu(Guangdong YSD Survey and Design Co.,Ltd.,Foshan 528000,China)
出处
《吉林水利》
2026年第3期57-63,共7页
Jilin Water Resources
关键词
感潮河段
前后二级挡水闸
分洪调度
渗流安全
Tidal river section
Front and rear two-level flood-blocking gates
Flood diversion operation
Seepage safety
