System Reliability Assessment by Method of Moments

Abstract

The computational assessment of system reliability of structures has remained a challenge in the field of reliability engineering. Calculation of the failure probability for a system is generally difficult even if the potential failure modes are known or can be identified, because available analytical methods require determination of the sensitivity of performance functions, information on mutual correlations among potential failure modes, and determination of design points. In the present paper, a method based on moment approximations is proposed for structural system reliability assessment that is applicable to both series and nonseries systems. The point estimate method is applied to evaluate the first few moments of the system performance function of a structure from which the momentbased reliability index and failure probability can be evaluated without Monte Carlo simulations. The procedure does not require the computation of derivatives, nor determination of the design point and computation of mutual correlations among failure modes; thus, it should be computationally effective for structural assessment of system reliability.

Compressed Flexible Steel Reinforced Concrete Elements Investigation

“…It should be noted that there are other options for reducing the cross-section, in particular, to box or twin-plate, but this reduces the flexibility of the column, which does not correspond to the data obtained during the experimental tests. To determine the stability of the central compression will use the formula (10):…”

Reliability-Based Robust Design of Mechanical Components with Correlated Failure Modes Based on Moment Method

“…To overcome this problem, the moment method could estimate the reliability index by making use of the first few moments of random variables. One of the moment methods called high-order moment standardization technique is adopted here and the reliability index of each failure mode could be expressed as follows according to the theory in [11]:…”

“…Probabilistic network evaluation technique is proposed to solve the system reliaiblty problem of large structure system [10]. Zhao and Ang proposed a method based on moment approximations for structural system reliability assessment which is applicable to 2 Advances in Mechanical Engineering both series and nonseries systems [11]. The work in [12] used a matrix-based system reliability (MSR) method to estimate the probabilities of complex system events by simple matrix calculations.…”

A Reliability Sensitivity Analysis Method Based On Saddlepoint Approximation

“…As an important tool for quantifying and dealing with all kinds of uncertainties, reliability sensitivity analysis could provide not only the reliability level, but also the impact of the input uncertainties on the system performance. Generally, the reliability sensitivity analysis methods may be divided into sampling simulation methods [6,8] and approximate methods [3,9,10,12] . Approximate methods such as the well-known first-and second-order reliability methods (FORM/SORM) [7] and moment matching methods [12] are often used for the failure probability evaluation.…”