揭阳大桥主桥设计关键技术

Key Technologies in Design of Main Bridge of Jieyang Bridge

摘要:

揭阳大桥主桥全长576 m，为（138+300+138）m双塔双索面钢-混组合梁斜拉桥，桥面宽度32.4 m。主梁采用双工字形组合梁，斜拉索和主梁的锚固采用锚拉板锚固形式。为有效解决桥面板开裂问题，提出了局部采用超高韧性混凝土材料（UHPC）桥面板方案；另外，因主桥抗震、抗风设防要求较高，为有效减小主塔地震力，增加主桥抗风性能，对塔梁间纵向阻尼器进行了参数敏感性分析，确定了阻尼器的合理设计参数，同时通过风洞试验，确定在外侧小纵梁处设2道下稳定板的气动措施可提高颤振临界风速，降低涡激共振振幅，使大桥具有足够的抗风稳定性。

Abstract:

The main bridge of Jieyang bridge is 576 m long, and is a steel-concrete composite girder cable-stayed bridge with (138 + 300 + 138) m double pylons and double cable planes. The width of the deck is 32.4 m. The main girder is the I-shaped composite girder. The stayed cable and the main girder are anchored by anchor pulling plate. In order to effectively solve the problems of deck creaking, the scheme of partially using the ultra-high performance concrete (UHPC) deck slab is proposed. In addition, in order to effectively reduce the seismic force of the main pylon, the wind resistance of the main bridge should be increased because of high anti-seismic and wind resistance requirements of the main bridge. The parameters sensitivity analysis of the longitudinal damper between the pylon and beam is carried out, and the reasonable design parameters of the damper are determined; At the same time, through the wind tunnel test, it is determined that the aerodynamic measure of installing two lower stabilizing plates at the outer small longitudinal beam can increase the flutter critical wind speed, reduce the vortex-induced resonance amplitude, and make the bridge have enough wind-resistant stability.