Use of optimization for automatic grouping of beam cross-section dimensions in reinforced concrete building structures

摘要: Abstract In the development of structural designs, in general, designers avoid varying size elements, seeking to group them as much possible. These groupings produce aesthetic effects and facilitate formwork design for reinforced concrete frames, checks, implementation. Therefore, elements are pre-grouped into a smaller number different cross-sections provide an interesting practical solution. However, outcome is highly dependent on this grouping because dimension each element and, consequently, overall cost, will be determined by that most stressed group. This paper minimizes costs beams buildings using grid model. The sizing performed according Brazilian NBR 6118 standard [1], taking account flexural, shearing, torsional, web reinforcements, addition checks service limit states (deflection maximum crack opening). determining beam height leads lowest global automatic determination optimized performed, required groups. Several numerical analyses were computational implementation developed formulation. presents results obtained from analysis two floors. evidence chosen procedure may significant reduction cost structure, even small cross-sections. Thus, optimum dimensions less designer’s experience sensitivity. proposed easy implement generate consumption material when incorporated daily routine project offices.