利用ANSYS建立某下承式钢管混凝土拱桥有限元模型。编写基于三轴车辆作用下车桥耦合振动程序,数值模拟车桥相互作用响应,分析车速、路面粗糙度2个因素对主梁1/4跨及跨中处的冲击系数影响。同时使用DHDAS动态信号采集分析系统现场测试该桥,分析车辆以不同行车速度过桥时主梁跨中处的振动响应。研究表明:数值分析结果与实测结果吻合较好;车速在某一范围内车辆冲击系数要大于规范值;路面不平顺相对于行车速度对桥梁振动影响更加明显。
ANSYS was used to establish the finite element model of the concrete filled steel tube arch bridge.The vehicle-bridge coupled vibration program was written based on the action of three-axle vehicle and simulate the vehicle-bridge interaction response. The influence of speed and road surface roughness on the impact factor of 1/4 main span and mid span was analyzed. At the same time,the DHDAS dynamic signal acquisition and analysis system were used to test the bridge on the spot. Results showed that the numerical analysis results were in good agreement with the experimental results. The impact factor was larger than code value when the vehicle speed was in a certain range. The influence of road surface roughness on the vibration of the bridge was more obvious than the vehicle speed.