Stochastic Reliability-Based Design Optimization Framework for the Steel Plate Girder with Corrugated Web Subjected to Corrosion

Abstract

This paper proposes the framework for reliability-based design optimization (RBDO) of structural elements with an example based on the corrugated web I-girder. It tackles the problem of topological optimization of corroding structures with uncertainties. Engineering restrictions follow a concept of the limit states (LS) and extend it for stability and eigenfrequency assessment. The reliability constraints include all the LS; they are computed according to first- and second-order reliability methods. The RBDO example minimizes the bridge girder cross-section while satisfying the structural reliability level for the ultimate and the serviceability limit states, stability, and eigenfrequency. It takes into consideration two uncorrelated random effects, i.e., manufacturing imperfection and corrosion. They are both Gaussian; the first of them is applied at assembly time, while the second is applied according to the time series. The example confronts three independent FEM models with an increasing level of detailing, and compares RBDO results for three concurrent probabilistic methods, i.e., the iterative stochastic perturbation technique (ISPT), the semi-analytical method, and the Monte Carlo simulation. This study proves that the RBDO analysis is feasible even for computationally demanding structures, can support automation of structural design, and that the level of detailing in the FEM models influences its results. Finally, it exemplifies that reliability restrictions for LS are much more rigorous than for their deterministic counterparts, and that the fastest ISPT method is sufficiently accurate for probabilistic calculations in this RBDO.

Innovative Design Techniques for Sinusoidal-Web Beams: A Reliability-Based Optimization Approach

“…Expanding on the insights acquired from parametric studies and reliability-based designs, the optimization of structures [31,32], with a specific focus on the integration of sinusoidal-web steel beams, has become a central theme in contemporary structural engineering research [33]. With an emphasis on the corrugated web I-girder, Sokołowski and Kami ński [34] introduced a framework for the topological optimization of corroding structures, based on a reliability-based design. By concentrating on the optimal weight design and parameter effects, Shon et al [35] developed an optimization algorithm for sinusoidal-web steel beams.…”

Degradation of Steel Rebar Tensile Properties Affected by Longitudinal Non-Uniform Corrosion

“…Researchers focusing on the stochasticity of corrosion have made efforts to establish stochastic models of steel bars [ 32 ] and structural steel [ 33 ]. Corrosion randomness was also considered in the reliability analysis [ 34 ] and reliability-based design optimization [ 35 ]. Nevertheless, the study on random field problems requires a large number of samples and to consider many variables.…”

Special Issue: “Computational Mechanics of Structures and Materials”

“…They proposed a framework for the reliability-based design optimization (RBDO) of structural elements, considering a corrugated web I-girder as an example. Several numerical approaches have been compared in this context [ 9 ].…”