并列双箱梁桥面风致涡激振动试验研究

Experimental Study on Wind-Induced Vortex Shedding of Parallel Box-Girder Bridge

基于两座具有并列双箱梁的缆索承重桥梁,做了一系列的弹性悬挂节段模型风洞试验.结果表明,双桥面之间存在不可忽略的气动干扰效应,它对双桥面桥梁的涡激振动会产生不利影响.以平胜桥主梁节段模型为基础的风洞试验研究表明,并列双桥面之间的气动干扰效应随着桥面间距的增加而减弱,从而使主梁的涡激振动特性随两桥面之间的距离而变化,而增加阻尼是抑制双桥面涡激振动的有效手段.

Based on two cable supported bridges with parallel box girder, a series of wind tunnel tests of the sectional models were performed to study the vortex-induced vibration of the decks. In the tests, two sectional models were all suspended with 8 springs in wind tunnel to consider the aerodynamic interference between the two decks. The test results have shown that. the aerodynamic interference can not be ignored and it will affect the vortex-induced vibration of both decks. The model of Pingsheng Bridge was selected to study the effect of the distance between two decks on the vortex shedding. The tests results indicated that the aerodynamic interference effect weakened with the increase of distance, and then the response of the vortex-induced vibration of the girders varied with it. The research has also shown that it is effective to restrain the vortex shedding by increasing the damping ratio.