Name: JONAS DA ROCHA
Publication date: 31/03/2025
Examining board:
Name |
Role |
|---|---|
| ADENILCIA FERNANDA GROBERIO CALENZANI | Presidente |
| JANAINA PENA SOARES DE OLIVEIRA | Examinador Externo |
| JOAO VICTOR FRAGOSO DIAS | Coorientador |
| JULIANA DA CRUZ VIANNA PIRES | Examinador Externo |
Summary: The study of technologies aimed at better utilization and optimization
of materials to make projects more economical, sustainable, and faster to
execute is of utmost importance. Projects that use composite beams with
precast hollow-core concrete slabs are scarce, partly due to a lack of
knowledge about the system and its design methods. However, in 2024, the
ABNT NBR 8800 standard was updated to include normative prescriptions and
the design methodology for composite beams with precast hollow-core
concrete slabs, which served as the basis for this work. A computational
program was developed to automate the analysis and design calculations of
steel composite beams with precast hollow-core concrete slabs, following the
proposed methodology for internal and edge composite beams composed of
doubly symmetric I-sections and precast hollow-core slabs. The procedures
were outlined in design flowcharts and later implemented in the program, which
was developed using VBA (Visual Basic for Applications). The program selects
the lightest rolled or welded I-section that meets the acting demands, providing
a calculation report at the end with the main design information. The
computational tool was validated through a comparison with an adapted
example from the Gerdau composite beams with hollow-core slabs manual
(Queiroz, Rocha, and Filho, 2017), which, along with NBR 8800:2024, served
as a foundation for the methodology presented here. Furthermore, a
parametric study with 72 composite beam models with hollow-core slabs was
conducted to analyze the ultimate limit states (ULS) governing the design of
this type of structure, as well as the influence of the concrete topping thickness
and the characteristic compressive strength of concrete () on beam
strength. The results showed that the design was governed by the balanced
phase, where the applied moment is generated by the support of two hollowcore
panels on the top flange of the steel section in cases of shorter beam and
slab spans, and by the composite phase in cases of longer beam and slab
spans. Additionally, the increase in beam strength with higher values was
significant when a compact-web profile was used but irrelevant when a semicompact-
web profile was adopted. The serviceability limit state (SLS) was not
