铰接板桥交通振动与声辐射算法及影响因素研究

铰接板桥是中国城乡公路桥梁中广泛采用的一种桥型，其在车辆作用下的振动，以及由此导致的结构声辐射问题对于桥梁周边的声环境具有较大影响。因此，针对铰接板桥的交通振动与噪声问题，提出了对应的分析方法并进行了验证。首先提出了该类桥型的车桥耦合振动高效算法，对各梁板建立独立的单梁模型，用铰接板梁法模拟各梁板之间的相互作用，由此实现车轮荷载在各梁板间的横向传递。然后用边界元法计算桥梁结构的声辐射，引入振动分析得到的桥梁振动速度，获得结构周边的声场。最后，用实际桥梁交通振动与声辐射实验进行了验证。基于当前方法，讨论了该类桥梁结构声辐射的影响因素。结果表明，加强横向联系、减小桥面粗糙度、采用无伸缩缝的连续桥面是降低结构声辐射的有效途径。

A COMPUTATIONAL METHOD FOR THE TRAFFIC VIBRATION AND SOUND RADIATION OF HINGED-JOINTED SLAB BRIDGE AND THE ANALYSIS OF INFLUENCING FACTORS

Hinged-jointed slab bridges are widely used in urban and rural roads in China. The traffic vibration and structure-borne sound of this kind of bridge have great influence on the acoustic environment nearby. In this paper, a procedure for analyzing the vibration and sound radiation of this kind of bridge is introduced and verified. Firstly, a computational method of vehicle-bridge coupling vibration is presented for this kind of bridge, in which the bridge is modeled by separated beams, the interaction between them are simulated by the shear key deck method, and the tire loads of vehicles are distributed on these beams. Secondly, the boundary element method is used to calculate the sound radiation of the bridge, while the vibration velocity of the bridge structure from the vibration analysis is introduced. Finally, the proposed method is validated in the experiment of a practical bridge. Based on the current method, the influencing factors of sound radiation of this bridge are discussed. The results indicate that strengthening the lateral connection of the beams, reducing the roughness of the road surface and adopting the continuous bridge deck without expansion joints are effective ways to decrease the sound radiation of hinged-jointed slab bridges.