跌坎消力池上举力特性试验研究

摘要

Based on stability study of spillway stilling pool slab of a hydropower station, characteristics of uplift force in stilling basin with drop sill was researched by performing model test. The results show that the drop sill height has a significant impact on the uplift force on the stilling basin plate, and appropriately increasing the drop sill height can reduce the uplift force;the relationship between the uplift force and hydraulic conditions is established;when the stilling basin body and hydraulic conditions are given, the maximum uplift force can be obtained by the empirical formula. According to the stable condition of bottom plate, the plate anchoring force can be calculated to maintain stable;fluctuating pressure on the plate and uplift force per unit area is substantially linear relationship, and the value of the uplift force per unit area is approximately 53% of fluctuating pressure. The fluctuating uplift force and the maximum uplift force are substantially linear relationship, and the value of the fluctuating uplift force per unit area is about 24% of the maximum uplift force.%基于某水电站溢洪道消力池底板的稳定性分析，对跌坎消力池底板的上举力特性进行了试验研究。结果表明：跌坎高度比对消力池底板上举力有显著影响，适当增加跌坎高度可以降低消力池底板块上举力。由水力条件建立了底板块单位面积最大上举力的估算公式，根据估算得到的最大上举力可以计算底板稳定所需的锚固力；底板的脉动压力和单位面积脉动上举力基本呈线性关系，在数值上单位面积脉动上举力约为脉动压力的53％；底板脉动上举力和最大上举力基本呈线性关系，在数值上单位面积脉动上举力约为最大上举力的24％。