反拱水垫塘拱圈多底板块振动特性的理论分析和试验研究

Theoretical Analysis and Experimental Research on the Ring Slabs'Vibration of Inverted Arch Plunge Pool

以溪洛渡拱坝下游出流条件和反拱水垫塘体型为参考,在拱圈底板块间止水破坏、底板块锚筋失效的极端条件下,对拱圈弹性底板块的振动特性进行了研究,得到拱圈底板块振动位移幅值沿流程、沿拱圈的分布规律及其时域和频域特性。研究结果表明,随拱圈底板块数目的增多,部分板块形成局部拱作用,拱圈底板块锚固失效的连锁反应及缝隙宽度的累加效应是造成底板破坏的主要原因。

With reference to the inverted arch plunge arch dam as a prototype, a research is conducted on pool and with the surface outlet of Xiluodu the vibrating characteristics of the elastic a- pron slabs on an arch ring upon conditions that all the seal installations between the apron slabs and the anchoring on slabs are out of action. The regularities of distribution on slab＇s amplitudes of vibrating displacement, and its characteristics of vibration both in the time domain and the frequency one are obtained from the experiment. Meanwhile, the factors that cause the instability and breakdown in the bottom slabs of the inverted arch pool are found out. This experimental re- search has proved that with an increase in the bottom slabs, some of them are humped up and that the chain reaction in the breakdown of anchoring on slabs and the increasing width in the gaps between slabs are the main cause for the spoiling of slabs.