Experimental and Numerical Investigation of Self Compacting Reinforced Concrete Dapped End Beams Strengthened with CFRP Sheets

Abstract

This study aims to investigate experimentally the behavior of self-compacting reinforced concrete dapped end beams strengthened with CFRP sheets and, then theoretically by ANSYS 15.0 software. The experimental program consists of testing 14-specimens each of dimensions (200x400x1500 mm) with two values of Shear span to depth effective (a/d), namely (1.5 and 1.0). Two of the beams are a control beams (with full reinforcement), and four beams with reduced reinforcement in hanger and nib regions. The other beams have been strengthened with several configurations by CFRP sheets for the same values of (a/d), the comparison between results included load-deflection curves and cracked specimens. It was found that the strut and tie model (STM) is very conservative somehow, reduction the nib reinforcements by about (60%), in reduction in failure load by about (35% and 15%) for the two values of (a/d). With respect to the strengthened specimens, it observed that the strengthening with inclined CFRP strips (450) yielded better results in comparison with other configurations. The improvement in load capacity was about (23%) for (a/d=1.5 and 1.0). Also, it is found that the nonlinear model adopted in the present work compered the experimental tests yielded a good agreement with difference of about (12%).

Enhancement of the behaviour of reinforced concrete dapped end beams including single-pocket loaded by a vertical concentrated force

“…al. [20] examined several strengthening configurations for the dapped ends using CFRP sheet. Such configurations included the inclined, horizontal and the combined arrangements.…”

Numerical Investigation on Effect of Opening Ratio on Structural Performance of Reinforced Concrete Deep Beam Reinforced with CFRP Enhancements

“…To validate the ability of the selected concrete model for studying the behavior of deep beams, a validating model was created and compared with an experimental study [32]. Three selected experimental cases, a deep beam with and without an opening and an RC deep beam with opening plus CFRP stirrups [32], were selected to validate the RC model behaviors and results. This test serves as a source for comparison between the experi-mental results and the numerical analysis.…”

“…This test serves as a source for comparison between the experi-mental results and the numerical analysis. In the current study conducted by Nadir [32], simply supported deep beams were instrumented with devices to measure the mid-span deflections and loads. Figure 2 illustrates the cross-section and loading configuration of the experimentally tested beams.…”

“…A perfect bond was assumed by employing the embedded strategy between the grid reinforcement and the surrounding concrete material. This was considered reasonable because ribbed and bent bars were used in the experimental tests conducted by Nadir [32]. In addition, the truss elements are used in two and three dimensions to model slender, line-like structures that support loading only along the element's axis or centerline.…”

Reinforced Concrete Dapped End Beams – State of the Art

“…This was the case even for the lower concrete strength specimens. Shakir et al (2018) tested experimentally 14-specimens to study the performance of reinforced self-compacting concrete dapped end beams strengthened with CFRP sheets. Two values of (a/d) namely (1.5 and 1.0) were adopted.…”