Probabilistic Approach to Limit States of a Steel Dome

Abstract

In this paper, Numpress Explore software, developed at the Institute of Fundamental Technological Research of the Polish Academy of Sciences (IPPT PAN), was used to conduct reliability analyses. For static-strength calculations, the MES3D module, designed by the authors, was employed. Ultimate limit state was defined as condition of non-exceedance of the capacity value, resulting from the stability criterion of the bent and compressed element. The serviceability limit state was defined as the condition of non-exceedance of allowable vertical displacement. The above conditions constitute implicit forms of random variable functions; therefore, it was necessary to build an interface between the Numpress Explore and MES3D programs. In the study, a comparative analysis of two cases was carried out. As regards the first case, all adopted random variables had a normal distribution. The second case involved a more accurate description of the quantities mentioned. A normal distribution can be adopted for the description of, e.g., the randomness in the location of the structure nodes, and also the randomness of the multiplier of permanent loads. In actual systems, the distribution of certain loads deviates substantially from the Gaussian distribution. Consequently, adopting the assumption that the loads have a normal distribution can lead to gross errors in the assessment of structural safety. The distribution of loads resulting from atmospheric conditions is decidedly non-Gaussian in character. The Gumbel distribution was used in this study to describe snow and wind loads. The modulus of elasticity and cross-sectional area were described by means of a log-normal distribution. The adopted random variables were independent. Additionally, based on an analysis of the elasticity index, the random variables most affect the failure probability in the ultimate limit state and serviceability limit state were estimated.

Qualitative and quantitative analysis of tensegrity domes

“…The research on standard steel domes concerns increasing the load capacity of the structure of the load-bearing capacity of the structure [1] and methods of taking into account the impact of non-uniform loads [2][3][4][5][6] or imperfections [7][8][9]. Most of the research focuses on optimization design [10,11], stability analysis [12,13], and reliability analysis [14,15].…”

The comparison of robust and reliability based design optimization

“…Neural networks and the proprietary MES module were used to create descriptions of this formula. The reliability of single-layer steel domes using FORM and Monte Carlo was the main subject of papers Radoń, 2019, 2020;Radoń et al, 2021).…”

A Predictive Approach for Disassembly Line Balancing Problems

“…It is assumed that the duration of each disassembly joint n i j , of product i, i = 1 …, d is described by truncated normal distribution with parameters changing with time. The normal distributions are popularly used to describe manufacturing processes, e.g., in the six sigma process measurement method, the goal is to achieve 3.4 defects per million opportunities (DPMO, defects per million opportunities) [ 33 , 34 ]. Disassembly operation time predictions are built based on historical operation times in a certain number of periods of the same length.…”