Perforated cold-formed steel (PCFS) back-to-back channel beams are increasingly gaining
popularity in the building sector due to their numerous advantages and economic benefits.
Notably, their lightweight nature allows for easier handling and installation, while
the holes in PCFS beams facilitate the accommodation of utilities such as electrical
and plumbing installations. In this study, a geometrically and materially nonlinear
finite element model (FEM) was developed and validated using experimental data from
existing literature. The validation results indicated a strong correlation, with the
ratios of FEM and Direct Strength Method (DSM) predictions to experimental outcomes
being 1.007 and 0.945, respectively. This demonstrates a significant agreement among
experimental data, FEM analysis, and moment capacity estimations based on American
Iron and Steel Institute (AISI) Standards, although AISI predictions were found to
underestimate moment capacities by approximately 5.5 %. Following model validation,
an extensive parametric study involving 192 FEM simulations was conducted to evaluate
the influence of hole size, hole geometry, edge stiffeners, and batten reinforcements
on the moment-carrying capacity of built-up I-shaped CFS beams. The findings indicate
that, in comparison with beams having plain webs, the presence of web openings leads
to a reduction in moment capacity of approximately 10 %, 9 %, 9 %, and 6 % for circular,
slotted, square, and rectangular holes, respectively. Furthermore, the results demonstrate
that the inclusion of stiffeners around web openings, together with batten reinforcement,
markedly improves the structural performance of PCFS built-up beams. In particular,
the maximum enhancement in moment capacity of beams with batten reinforcement and
edge-stiffened holes, relative to those with unstiffened holes, is about 9 %, 10 %,
13 %, and 14 % for circular, rectangular, square, and slotted holes, respectively.
Overall, the findings offer valuable insights into the structural behavior of perforated
built-up CFS beams and emphasize the effectiveness of web hole stiffening and batten
reinforcement strategies in mitigating strength reductions caused by web perforations.
