【摘要】 运用ANSYS中的概率设计模块(PDS)技术,将蒙特卡罗法(MC)和响应面法(RSM)结合起来,针对无法列出极限状态方程的在役钢筋混凝土拱桥建立了有限元模型,并进行了可靠度分析。根据钢筋混凝土拱桥的实测资料,选取对结构可靠度影响大的随机变量作为输入参数,将拱桥的结构响应编写为ANSYS的APDL语言,建立可靠度计算的参数化模型。利用ANSYS中的PDS模块技术拟合结构的响应面方程,对拟合的响应面函数进行2 000次抽样,得到函数的统计参数。然后根据JC法的计算原理,用Matlab编程计算出拱桥上部结构的可靠指标。并根据钢筋混凝土拱桥的结构特点,将主拱圈、拱上立柱和桥面板作为串联体系进行系统可靠性分析,选取构件的最低可靠指标作为整个体系的可靠指标。最后探讨了随机变量对拱桥可靠度的灵敏度影响程度,得到拱圈、拱上立柱和桥面板3个构件中随机变量对功能函数的影响大小。更多还原

【Abstract】 Combining with the Monte Carlo method and the response surface method( RSM),using the probabilistic design system( PDS) module in ANSYS,the finite element model of an existing reinforced concrete arch bridge whose limit state equation cannot be explicitly formulated is established,and the reliability of the arch bridge is analyzed. According to the measured data of the reinforced concrete arch bridge,some random variables affecting the structural reliability are selected as input parameters,the structural response of the arch bridge is written as ANSYS APDL language,a parametric model of reliability calculation is established,and the structural response surface equation is fitted by the PDS module technique in ANSYS. The statistical parameters of the function are calculated through 2 000 times sampling of the fitted response surface function. Then,the reliability index of the arch bridge superstructure is calculated using Matlab programming based on JC method. Arch ring,spandrel column and bridge deck are taken as series system to investigate the system reliability in accordance with the structural characteristics of reinforced concrete arch bridge,the lowest reliability index of the superstructures is selected as the reliability index of the whole system. How random variables affect the sensitivity of the bridge reliability is discussed finally,the sensitivity magnitudes of random variables on the performance functions of the 3 structural components areobtained.更多还原