表孔弧形闸门空载振动原型试验研究

Prototype test research on non-load vibration of arc steel gate

针对龙羊峡水电站表孔弧形闸门存在的振动和异常声响问题 ,通过闸门的制作安装精度检测、启闭力测试、模态测试、动力响应测试、声响测试等原型试验方法 ,对闸门振动原因和特性 ,启闭力不均衡问题 ,支臂的应力应变特性、异常声响的原因和特性等进行深入地研究。研究成果表明 :(1)闸门在强振区的振动主要是弹性模量小的水封所激发 ,其根本的原因是闸门的轨道存在严重偏差和铰轴同心度超标 ;(2 )异常声响的主要来源是铰轴 ,其原因是两个铰轴同心度偏差较大和铰轴与轴套之间存在干摩擦所致 ;(3 )门体振动、支臂应力应变的交替变化、启闭力交替变化、铰轴异常声响它们有密切关系 ,其在强振区的主要频率 (1号门约 4Hz ;2号门约 3Hz)基本一致。

Aimed at the problem of vibration and abnormal noise of arc-gate in Longyangxia hydroelectric station,the vibrant cause and characteristic of the arc steel gate,the unbalance force during gate open and close,the stress and strain characteristic of the support arm,the cause and characteristic of the abnormal noise are deeply analyzed by means of the precise making and erection of gate,force test during gate open and close,modal test and dynamic responding test.From the above research work,the following conclusions may be obtained:(1)Strong vibration of arc steel gate due to the hydraulic seal with low modulus of elasticity;(2)Abnormal noise from the arc steel gate axes;(3)Close relations between vibration of gate and the alternant change of forces during gate open and close.