均匀设计和正交设计在试验次数相近的情况下,前者所选试验点均匀性更好,也更具代表性。该文将均匀设计与响应面法相结合,提出了结构可靠度的数值模拟新方法:基于均匀设计的响应面法、均匀设计响应面与蒙特卡罗抽样相结合的混合模拟法;介绍了利用均匀设计选取试验点构造响应面方程,求解可靠度的流程。结合一个门式框架的可靠度问题,基于ANSYS实现了上述新方法,并与经典的可靠度数值模拟方法进行了对比分析。均匀设计响应面法构造的结构极限状态函数精度更高、偏差更小,同时基于均匀设计响应面的混合模拟法不仅精度高,还可以大大提高试验效率。
The chosen experiment points of a uniform design(UD) is generally more uniform and representative than an orthogonal design(OD),even though in the case that the trial numbers of the two experiment design methods are near.In this paper,a new numerical simulation method for structural reliability analyses is firstly proposed,which incorporates a uniform design into the conventional response surface method,herein named as uniform design response surface method(UDRSM).And then,a hybrid simulation method(HSM) combing Monte Carlo Simulation(MCS) and UDRSM is put forward.The simulation process of the new method includes the following steps:(1) choosing testing points,(2) constructing response surface equation,and(3) calculating structural reliability.The two new methods are all implemented in ANSYS by using the deterministic finite element method.A portal frame is taken as a numerical example.The accuracy and efficiency of the new methods are demonstrated by contrasting the new proposed method with the classical numerical simulation methods including Monte Carlo simulation(MCS) and orthogonal design response surface method(ODRSM).It is shown that the limit state function of UDRSM is more accurate than other methods,and that HSM is more efficient than others.