Experimental and Numerical Investigation of Shear Behavior in Beams with Partial Replacement of Natural Coarse Aggregate by Recycled Brick Aggregate

Abstract

Sustainability in construction has become increasingly important in recent decades due to the depletion of non-renewable resources. As a potential solution, recycled brick aggregate (RBA) has gained attention as an alternative to conventional natural aggregate (NA) in concrete. This research investigates the viability of recycled brick aggregate (RBA) as an alternative to natural aggregate in structural applications, specifically focusing on the shear behavior of reinforced concrete beams without stirrups. The study employed both experimental testing and numerical modeling to evaluate the structural performance of beams incorporating various proportions of RBA. Seven reinforced concrete beams of dimensions 200 mm × 300 mm × 1800 mm were constructed with RBA replacement ratios of 0%, 25%, 50%, 75%, and 100%. Two distinct treatment methods were implemented to enhance the properties of RBA. All specimens were designed according to ACI 318-19 specifications to ensure shear failure. The beams were subjected to four-point bending tests to evaluate their shear strength characteristics, and the experimental results were complemented by numerical simulations using OpenSeesPy software. The experimental findings revealed that beams constructed with treated RBA exhibited shear strength characteristics comparable to those of conventional natural aggregate concrete beams. The numerical modeling demonstrated consistent agreement with experimental results, showing similar trends in shear strength reduction as RBA replacement ratios increased. While slight variations were observed between experimental and numerical results, both methods validated the potential of treated RBA as a viable alternative in structural applications. This research contributes significantly to the existing knowledge base regarding sustainable construction practices by providing comprehensive data on the structural behavior of RBA concrete beams. The findings offer valuable insights for the implementation of RBA in structural elements, particularly in applications where shear strength is a critical design consideration. The results demonstrate that with appropriate treatment methods, RBA can be effectively utilized in structural concrete while maintaining essential mechanical properties