title: Refinement of Strut-and-Tie Model for Reinforced Concrete Deep Beams.
abstract: Deep beams are commonly used in tall buildings, offshore structures, and foundations. According to many codes and standards, strut-and-tie model (STM) is recommended as a rational approach for deep beam analyses. This research focuses on the STM recommended by ACI 318-11 and AASHTO LRFD and uses experimental results to modify the strut effectiveness factor in STM for reinforced concrete (RC) deep beams. This study aims to refine STM through the strut effectiveness factor and increase result accuracy. Six RC deep beams with different shear span to effective-depth ratios (a/d) of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00 were experimentally tested under a four-point bending set-up. The ultimate shear strength of deep beams obtained from non-linear finite element modeling and STM recommended by ACI 318-11 as well as AASHTO LRFD (2012) were compared with the experimental results. An empirical equation was proposed to modify the principal tensile strain value in the bottle-shaped strut of deep beams. The equation of the strut effectiveness factor from AASHTTO LRFD was then modified through the aforementioned empirical equation. An investigation on the failure mode and crack propagation in RC deep beams subjected to load was also conducted.
authors.affiliation: Department of Civil Engineering, Faculty of Science, Engineering, Technology and Mathematics (FOSTEM), INTI International University, 71800, Nilai, Malaysia.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Panjehpour
authors.affiliation: Department of Civil Engineering, Faculty of Engineering, University of Malaya, 50603, Kuala Lumpur, Malaysia.
authors.forename: Hwa Kian
authors.initials: HK
authors.lastname: Chai
authors.affiliation: DURA Technology Sdn Bhd, Ipoh, Malaysia.
authors.forename: Yen Lei
authors.initials: YL
authors.lastname: Voo
mesh_terms: D003252:Construction Materials; D005160:Facility Design and Construction; D020342:Finite Element Analysis; D008962:Models, Theoretical; D033081:Shear Strength; D013718:Tensile Strength