【摘要】 采用有限元软件ANSYS建立铅芯橡胶支座(LRB)隔震公路连续梁桥模型,利用Newmark时间积分法求解依据达朗贝尔原理建立的车桥耦合振动方程,并编制相应的MATLAB程序,利用该程序对LRB隔震公路连续梁桥在车辆荷载作用下的动力性能进行分析.分析结果表明:随着隔震周期的增大,桥墩处的LRB已发生屈服,严重影响车辆的行驶安全;隔震周期的改变对车体侧翻角位移影响较大,而对车体点头角位移影响甚微;增大LRB的阻尼,可有效降低支座和梁体横桥向位移;LRB阻尼的改变对车体竖向振动加速度、侧翻角加速度和点头加速度的影响均不明显;增大行车速度,会降低梁体横桥向位移;加速与减速行驶时,各验算点梁体横桥向位移峰值出现的位置有显著不同.更多还原

【Abstract】 A finite element method model of seismic isolation continuous girder highway bridge is established by using the ANSYS program,and a coupling dynamic equations of vehicle-bridge is established by D′Alembert principle.The equation is solved by using Newmark time integral method and its relevant MATLAB program which analyzes the dynamic performance of highway seismic isolated bridge under action of vehicle load is proposed.The results show that the LRB of pier is yielded with isolated period of the bridge(IPB) increasing which affects the security of the vehicle.Different IPBs have big effect on the side rolling displacement of bodywork,but they have little effect on the nodding displacement of bodywork.Transversal displacement response of LRB and girder is reduced by increasing the damping ratio of LRB.Different damping ratios of LRB have little effect on the vertical vibration acceleration,side rolling acceleration and nodding acceleration of bodywork.Increase of the vehicle speed makes the girder transverse displacement become greater smaller.When the vehicle accelerates or decelerates driving,the occurring positions of peak value of girder transverse displacement for key points show significant differences.更多还原