Proposed Shear Design Method for Continuous Reinforced Concrete Beams Considering Moment Redistribution | ||||
| JES. Journal of Engineering Sciences | ||||
| Articles in Press, Accepted Manuscript, Available Online from 31 August 2025 | ||||
| Document Type: Research Paper | ||||
| DOI: 10.21608/jesaun.2025.376890.1483 | ||||
 View on SCiNiTO | ||||
| Authors | ||||
Tarek M Abdelaleleem   1; Mohamed Elsayed2; Hesham M Diab 3; Yahia A. Hassanean4
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| 1Reinforced Concrete Structures (RCS) | ||||
| 2sohag university | ||||
| 3Assiut | ||||
| 4Assiut university, Assiut city, Egypt | ||||
| Abstract | ||||
| Current shear design provisions for continuous reinforced concrete (RC) beams inadequately account for the coupled effects of shear span-to-depth ratio (a/d) and moment redistribution, often leading to conservative or unsafe predictions. This study addresses this gap through an integrated approach combining nonlinear finite element modelling and full-scale laboratory testing. Eleven continuous beam models with varying (a/d) ratios and transverse reinforcement percentages were analysed using ANSYS, and three full-scale RC beams were tested under symmetrical four-point loading. Results show that reducing (a/d) increases shear strength by up to 42% but reduces redistribution capacity, while changes in transverse reinforcement ratio have negligible influence on redistribution. A new empirical equation is proposed to predict moment redistribution ratios, incorporating $a/d$ effects, with prediction errors within ±5% of experimental and numerical results. Compared with current code expressions, the proposed model offers consistently higher accuracy across a wide range of geometries. The findings provide a unified framework linking shear capacity and redistribution limits, enabling more rational and reliable shear design provisions for continuous RC beams in major structural codes. | ||||
| Keywords | ||||
| Shear strength; web reinforcement ratio; Moment redistribution; Continuous beams; Finite element modeling | ||||
| References | ||||
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