中文摘要：

根据超载车辆分布较多的府店路荷载调查资料,开展了一般运行状态和密集运行状态下的疲劳荷载谱模拟计算研究。通过公路桥梁荷载效应分析,得到了一般运行状态和密集运行状态下的应力时程曲线,利用雨流计数法建立公路桥梁应力幅谱Δσ-ni。根据线性累积损伤原则,推导出公路桥梁疲劳可靠性分析的等效应力幅Δσe的计算公式,定义了便于实际应用的荷载效应比。模拟计算表明,在车辆数和车辆种类相同的情况下,密集运行状态下产生的荷载效应绝对值大,但由于密集运行的车辆产生持续集中的高应力,桥梁构件关键截面的应力差值较一般运行状态小,因此其等效应力幅偏小。

英文摘要：

The on-site survey from Fudian Road indicated that overloaded vehicles account for a significant high proportion of the overall traffic volume.Therefore,fatigue load spectra in normal traffic state and intensive traffic state were simulated based on this information.The stress time history curves of steel rebar and concrete in two states were obtained though highway bridge load effect analysis.Stress range spectrum Δσ-ni was obtained by using rain-flow counting method.According to linear accumulative damage criteria,the equation for equivalent stress range Δσe was derived and ratio of load effect was defined for practical application on bridge fatigue reliability analysis.The simulation shows that the absolute value of load effect under intensive traffic state is larger than that of normal traffic state with same vehicle queue,while the equivalent stress range is smaller than that of normal traffic state due to the sustained high stress under intensive traffic state and the smaller stress difference in the critical section of bridge member.