Prediction of Failure Loads of RC Dapped-End Beams

Abstract

Shear failure remains the governing mode of failure for reinforced concrete (RC) dapped-end beams. Dapped-ends are commonly classified as disturbed regions (D-regions). Strut and tie model (STM) is a simple and rational way that can be applied to analyze D-regions. The current design codes such as ACI-318-08, Euro Code 2 and BS 8110 facilitate STM to predict the failure loads. In addition, the failure loads may be also predicted using the empirical method proposed in PCI Design Handbook. In this paper, the failure loads were predicted for 24 RC dapped-end beams following different codes. The significant parameters such as concrete compressive strength, dapped-end section size, shear span-depth ratio, type and effective range of stirrups, bent form of the longitudinal reinforcement, amount of dapped-end reinforcements and hanger reinforcements were varied to study their effects against the predicted failure load for RC dapped-end beams according to different codes. These predicted results were compared with the available experimental results to investigate the ability of various codes to predict the failure load reliably. In this study, the comparison shows that PCI Design Handbook and ACI-318-08 can predict the failure loads for RC dapped-end beams more accurately.