Optimum Design of Fully Composite, Unstiffened, Built-Up, Hybrid Steel Girder Using GRG, NLR, and ANN Techniques

Abstract

Composite steel beams are commonly used element in multistorey steel buildings to enhance floor economy and serviceability and provide more clear height. Due to the low level of stress in the webs of such beams, hybrid sections are used where the flanges have higher strength than the webs. A lot of earlier research was carried out to optimize the design of the hybrid and nonhybrid composite steel beams under both static loading and dynamic behavior. However, there is still a need to develop a more practical optimization method. The aim of this research is to develop simple and practical equations to determine the optimum cross section dimensions for both shored and unshored, simply supported, hybrid and nonhybrid, composite steel beam under static loads. To achieve that goal, a research program of two phases was carried out. The first phase was generating a database of 504 composite beams with different steel grades for flanges and webs, subjected to different values of bending moment. The cross section of each beam in the database was optimized using GRG technique to minimize the cost considering the unit price of each steel grade. In the second phase, the generated database was divided into training and validation subsets and used to develop two predictive models using Nonlinear Regression (NLR) technique and Artificial Neural Network (ANN) technique to predict the optimum cross section dimensions and hence the optimum weight and cost. The accuracies of the developed models were measured in terms of average error percent. NLR and ANN models showed average error percent of 16% and 11%, respectively.

Estimating the Strength of Bi-Axially Loaded Track and Channel Cold Formed Composite Column using Different AI-Based Symbolic Regression Techniques

“…Selection: -Cold-formed steel columns can be made from various types of steel, such as ASTM A653/A653M or ASTM A1003/A1003M [25,26]. -Select the appropriate material grade based on factors like structural requirements, corrosion resistance, and fire rating [26].…”

“…Selection: -Cold-formed steel columns can be made from various types of steel, such as ASTM A653/A653M or ASTM A1003/A1003M [25,26]. -Select the appropriate material grade based on factors like structural requirements, corrosion resistance, and fire rating [26]. (c) Fabrication: -Fabricate the cold-formed steel columns according to the design specifications and applicable industry standards, such as AISI S100 or EN 1993-1-3 [27].…”

“…-Align and plumb the column, ensuring it is secured and vertical [27]. -Attach the column to the foundation or support using appropriate fasteners or anchor bolts [26]. -Ensure proper connections between the column and other structural elements, such as beams or floor systems [28].…”

Optimized Transverse–Longitudinal Hybrid Construction for Sustainable Design of Welded Steel Plate Girders

“…For example, web behavior under point loads [21], fatigue tests [22], web buckling resistance [23], and more recently on failure mechanisms [24], bending behavior [25][26][27], experimental shear behavior [28], elements with web openings [29,30], made by stainless steel [31], or with corrugated webs [32]. Other authors have proposed the use of predictive models such as nonlinear regression and artificial neural networks to obtain the optimal design of these elements [33]. Nevertheless, theoretical research on the advantages of this construction practice still needs to be completed, although some studies have revealed interesting information.…”