Abstract The use of appropriate reinforcement detailing in reinforced concrete coupling beams is crucial, particularly for those with a short span-to-depth ratio (ln/h < 2). These beams must be designed to exhibit ductile, inelastic behavior, thereby maintaining the stability of the coupled shear wall system. In practice, openings are often required in coupling beams to accommodate utility pipes for plumbing, electrical, and other building services. However, these openings can significantly alter the structural behavior and must be accounted for in the design. Since experimental investigation of various parameters is often expensive and time-consuming, this study employs computational modeling. A set of twelve reinforced concrete coupling beams, with and without openings, were analyzed using the non-linear finite element program ABAQUS to investigate their cyclic behavior. The beams featured different reinforcement details: conventional, diagonal confinement, and two configurations of rhombic details. All beams had identical dimensions of 200 mm in width and 400 mm in both depth and length (ln/h = 1). The primary variables were the presence, location, and reinforcement scheme around the openings. The results indicate that the solid coupling beam with diagonal reinforcement exhibited overall behavior superior to those with conventional or rhombic details. The introduction of an opening with relative dimensions of (lo/l = 0.125 and ho/t = 0.25) had a significant detrimental effect, especially when located at the mid-span. The behavior of beams with diagonal confinement was less affected by the presence of an opening than the other details, regardless of its location. Providing an opening 37.5 mm from the beam end reduced the shear capacity and maximum chord rotation by (10.2%, 30.4%), (5.5%, 15.6%), and (12.78%, 55.2%) for the conventional, diagonal confinement, and rhombic configuration 1 details, respectively, compared to their solid counterparts. Shifting the opening to the mid-span increased these reductions to (31.6%, 58.8%), (14.5%, 48.8%), (26.4%, 65.6%), and (19.2%, 50.2%) for the conventional, diagonal confinement, rhombic configuration 1, and rhombic configuration 2 details, respectively.
Ramadan et al. (Thu,) studied this question.