Multi-angle truss model for predicting the shear deformation of RC beams with low span-effective depth ratios. (15th May 2015)

• Record Type: Journal Article
• Authors: Wang, Tiao; Dai, Jian-Guo; Zheng, Jian-Jun
• Is Part Of: Engineering structures. Volume 91(2015:May 15)
• Page Start: 85
• Page End: 95
• Publication Date: 2015-05-15
• Subjects: RC beam -- Diagonal crack angle -- Shear deformation -- Multi-angle truss model -- Low span-effective depth ratio; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2015.02.035
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: The shear deformation of RC beams with low span-effective depth ratios is predicted. A multi-angle truss model is proposed to predict the diagonal crack angles. The diagonal cracks change with the moment along the shear span. The shear stiffness degradation of the member after the diagonal cracking is predicted. Abstract: The deflection of reinforced concrete (RC) beams with low span-effective depth ratios can be attributed equally to shear and flexural deformations. Although truss models can be used to evaluate shear deformation, their prediction accuracy is strongly dependent on how the diagonal crack angle is estimated. This paper presents the results from an experimental test of nine RC beams that failed in shear and had low span-effective depth ratios (i.e., a / h 0 < 3 ). It then proposes a multi-angle truss model for predicting ultimate shear deformation while considering the effect of the bending moment variation along the span on diagonal crack angles. An empirical formula is also presented to predict the shear stiffness degradation of RC beams up to the ultimate state through regression analyses. Numerical results show that the proposed multi-angle truss model can be used to predict the shear deformation of RC beams with low span-effective depth ratios with reasonable accuracy.