结构可靠性界限计算的包络面方法
Envelope Surface Method for Computing Structural Reliability Boundary

在结构二次二阶矩可靠性指标计算方法的基础上，结合包络面的思想，提出了基于包络面的结构可靠性界限计算方法。该方法在最可几失效域以旋转抛物面作为结构极限状态曲面的内外包络面，通过计算包络面的失效概率确定结构可靠性界限区间，并通过两个算例验证了该方法的可行性和计算精度。算例结果表明，该方法计算结果最接近蒙特卡洛方法的结果，相对误差小，计算精度高，具有工程实用价值。
Structural reliability boundary calculation method is proposed based on the Second order reliability method(SORM) and the envelope surface. Rotating paraboloids were applied as the interior and the exterior envelope surface of the limit state surface in most probable failure region, and the failure probability of envelope surface was calculated to determine the structural reliability boundary.The feasibility and accuracy of this method was verified by two numerical examples. The results obtained by this method agree well with those by the Monte Carlo method, and the relative error of this method is small