公路连续梁桥在横向多车作用下的振动响应研究

为研究横向多车作用下连续梁桥的振动响应,通过ANSYS建立公路连续箱梁桥的三维实体有限元模型,采用三维整车模型模拟三轴自卸汽车,引入路面不平顺的激励作用,建立多车车桥耦合振动方程.采用自编Matlab程序对横向并排两车、纵向前后两车及单车工况下桥梁的振动响应进行对比研究.结果表明:横向两车工况下的冲击系数与单车工况下的冲击系数接近,且为单车工况结果的0.4～1.3倍;纵向两车工况下的冲击系数绕单车工况下的冲击系数上下波动,且为单车工况结果的0.037～43.887倍.多车工况下的桥梁振动响应与车速、桥跨、车辆间距、路面等级等多种因素有关.

Studies on vibration response of the continuous girder highway bridge under horizontal multi-vehicle loads

In order to study the vibration response of continuous girder bridges under horizontal multi-vehicle loads, we used ANSYS to build the three-dimensional solid finite element model of continuous girder highway bridge, simulated three-axle dump truck by three-dimensional models, and considered the impact of road roughness to establish the multiple vehicle-bridge coupled vibration equation. We studied the vibration response of bridges under the horizontal two-vehicle, longitudinal two-vehicle and single-vehicle conditions by running MATLAB program. The result shows that the impact coefficients of the bridge under horizontal two-vehicle condition are close to that of single-vehicle condition, which are 0.4 ~ 1.3 times of the impact coefficients under the condition of single-vehicle; and the impact coefficients of the bridge under longitudinal two-vehicle condition fluctuate around that under single-vehicle condition, which are 0.037 ~43.89 times of the impact coefficients under the condition of single-vehicle. The vibration response of the bridge under multi-row vehicle loads is related to various factors such as vehicle velocity, bridge span, vehicle spacing, and the quality level of the bridge surface.