Regression models for ultimate hogging moment prediction of composite cellular beams

ABSTRACT

This work shows the accuracy and feasibility of polynomial regression models for the ultimate hogging moment prediction of composite cellular beams utilising different numbers of simulations. It discusses an attempt to reduce the number of samples in a finite element parametric study, which consists of using only the combination of extreme levels of each factor to develop the regression models. The parametric study has five parameters: cross-section dimensions, hogging moment distribution, unbraced length, opening diameter, and web-post width. The regression models are generated based on 32 (extreme values), 162 (extreme and intermediate values), and 360 numerical model results (all values). An ANOVA was performed on each regression model to assess the parameters’ order of relevance. According to ANOVA, the profile cross-section dimensions and hogging moment distribution were the most significant parameters on the beams’ ultimate moment for all regression models. As good precision was achieved, because of the insignificant differences within the regression models, it was observed that the combination of arbitrated extreme levels for the factors could significantly reduce the number of numerical simulations in a parametric study. Still, this approach could be used for any other type of structure to reduce the computational cost of future numerical investigations.

KEYWORDS:

• Composite cellular beams
• ultimate hogging moment; finite element modelling
• analysis of variance (ANOVA)
• polynomial regression models

Acknowledgments

This study was financed by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001 and National Council for Scientific and Technological Development (CNPq).

Disclosure statement

No potential conflict of interest was reported by the authors.

Notation

bf	=	flange width
bw	=	web-post width
bwe	=	end-post width
Cb	=	parameter associated with the distribution of bending moments
D0	=	opening diameter
d	=	depth of parent section
dg	=	depth of cellular beam
E	=	elasticity modulus of structural steel
fck-cylindrical	=	characteristic compressive cylindrical strength of concrete
fu	=	tensile strength
fy	=	yield strength
L	=	unrestrained length of composite beam
MA	=	moment at quarter-point in the unrestrained length
MB	=	moment at centerline in the unrestrained length
MC	=	moment at three-quarter-point in the unrestrained length
MFE	=	moment obtained from the finite element analysis
Mmax	=	maximum moment in the unrestrained length
tf	=	flange thickness
tw	=	web thickness
Mu	=	ultimate moment of beam
p	=	length between the opening diameter centers
n	=	Poisson ratio of structural steel

Notes

1. Computer’s configuration: AMD Ryzen 7 2700X Eight-core processor 3.70 GHz; 4 utilised domains; 16 GB RAM.

2. The maximum and minimum number of nodes within the finite element models were 305,750 and 229,993, respectively.

Additional information

Funding

The work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico [001]; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior .