梅花周边缝拱坝的破坏形式分析

Analysis on the failure types of Meihua arch dam with peripheral joints

对福建梅花周边缝拱坝安全度和破坏形式进行分析和模拟 ,表明该坝实际容许水深只有 2 0 8m ,溃坝前一直处于超载状态。大坝在水荷载作用下 ,岸坡坝段上滑引起河床坝段上抬 ,温升作用增加了上抬值 ,这种上抬对周边缝拱坝的整体稳定是不利的。破坏时先是周边缝岸坡部分和下部拉坏和剪坏 ,然后拱坝中部出现上抬破坏和坝肩发生剪切破坏 ,最终在库水作用下左、右坝体发生沿缝面的滑移和绕坝肩的转动破坏 。

The safety degree and failure types of the Meihua arch dam with peripheral joints in Fujian Province were analyzed and modeled The results showed that the actual water depth allowance of Meihua arch dam with peripheral joints is only 20.8 m and the dam was in overload state before its breach. Under the action of load, the upper slide of bank section of the dam caused the up lift of riverbed dam section, which is not favorable to the integrity stability of arch dam with peripheral joints. The model showed that its failure started from the bank slope with peripheral joint and the dam lower position and then the middle position and abutment of dam. Finally the dam body was destroyed wholly under the action of reservoir water, which is tally with the actual failure