改进响应面法及其在倾斜荷载桩可靠度分析中的应用

针对结构可靠度分析中常用的二次函数响应面法的不足,提出一种采用髙次响应面函数和利用JC法几何性质原理确定迭代中心点准则的响应面法。在此基础上,将该法应用于倾斜荷载桩的可靠性分析,计算了基于桩顶水平位移过大和桩身材料屈服这两种失效模式下的基桩可靠度,并连同蒙特卡罗法和二次函数响应面法的计算结果进行了比较。计算表明,改进的响应面法减少了计算的迭代次数,有效地提高了计算精度和数值试验的稳定性,可用于大型复杂结构的可靠性分析。

Improved response surface method and its application to Reliability analysis of piles under inclined loads

In consideration of the deficiencies of quadratic-function-response-surface method in structural reliability analysis,an improved response surface method is presented based on high-order-response-surface function and iterative rule with the geometry principle of JC method to decide center point.Reliability analysis of piles under inclined loads is done by the improved response surface method;reliability indices of piles with excessive top horizontal displacement and of piles with material yielding are calculated;and comparisons between results by the improved method presented and results by Monte-Carlo method and quadratic-function-response-surface method are done.The calculation demonstrates that iterative loops are reduced;precision of results and stability of numerical experiments are improved in the application of the improved response surface method;and the improved method is suitable for the reliability analysis of large-scale complicated structures.