Influence of Limit States on the Optimization of Reinforced Concrete Beams

Juliani, Marcela Alejandra; Gomes, Wellison José de Santana

doi:10.26678/abcm.mecsol2017.msl17-0018

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Following a research which was started by Juliani and Gomes [33], [34], the present paper proposes to analyze the optimal configuration of reinforced concrete plane frames, through the minimization of its costs, considering three cases of constraints: the first is related to ULS and SLS; the second refers only to the ULS; and the third is related only to the SLS. The design variables considered are the cross-section dimensions and the amount of longitudinal and transverse reinforcement of the structural elements.…”

Section: Introductionmentioning

confidence: 99%

Optimal configuration of RC frames considering ultimate and serviceability limit state constraints

Juliani

Gomes

2021

Rev. IBRACON Estrut. Mater.

Self Cite

View full text Add to dashboard Cite

Most current structural design codes are based on the concept of limit states, that is, when a structure fails to meet one of its purposes, it is said that it has reached its limit state. In the design of reinforced concrete structures, the Ultimate Limit State (ULS) and the Serviceability Limit State (SLS) must be checked. Therefore, this paper presents an optimization scheme for reinforced concrete plane frames, in which the objective is to minimize the cost of structures for three cases of constraints: the first is related to ULS and SLS; the second refers only to the ULS; and the third is related only to the SLS. Computational routines for checking limit states of beams and columns are implemented in MATLAB, following the requirements of the Brazilian code. Structural analyses are performed by using the MASTAN2 software, taking into account geometric nonlinearities and a simplified physical nonlinearity method. The objective function considers the cost of concrete, reinforcement and formwork, and the optimization problems are solved by genetic algorithms. Two numerical examples of frames are presented. Regarding the optimal characteristics related to each type of limit state, it is noted that the beams and columns tend to have larger and more reinforced cross sections in the case of the ULS. Even so, optimal structures related to the ULS often do not satisfy SLS and vice versa, which indicates that the optimal characteristics related to each limit state may be different. In addition, it is observed that the SLS is less restrictive than ULS.

show abstract

Section: Introductionmentioning

confidence: 99%