Abstract
Abstract This study focuses the light on the shear behavior of pre-cracked beams, and examines the feasibility of applying fracture mechanics concepts to widen the understanding of shear behavior and mechanisms. The experimental program contains ten beam specimens of high strength concrete (HSC) and steel fiber reinforced concrete (SFRC). Pre-cracks were embedded with different sizes and locations along the favorable path and orientation to shear failure. Three main scenarios of shear failure were reported with minute effect of pre-cracks. The geometrical effect is dominant with marginal effect of the material’s nonlinearity in case of severe pre-diagonal crack in HSC while the nonlinearity of the material is supreme to that of the geometrical effect for SFRC and shorter cracks. For verification, numerical simulation was conducted to examine the geometrical effect of the pre-diagonal tension crack in shear span on the structural behavior of RC beams. It is found numerically that, when the crack tip of the tensile crack is away from the tensile reinforcement, the closuring moment of tensile reinforcement increases, and as a result reduces the strain energy release rate. Therefore, the tensile cracks stop and the shear cracks keep propagating leading the failure mechanism to the end failure point.
Highlights
IntroductionCompression field theory (Collins 1978); modified compression field theory, Vecchio and Collins (1986); strut and tie model, Schlaich et al (1987) and the concept of 'compressive-force path' (CFP) Kotsovos (1988) have evolved in the general field of structural concrete design
The favorable site of pre cracks is targeted to be crossed by a stirrup; while the rest of generated cracks through the length of tested beam might propagate without being crossed by stirrups
Based on the numerical and experimental results obtained from current study the following conclusions can be drawn: 1-The driving force of shear crack increases with increasing the crack length while, the driving force of tensile crack decreases markedly with increasing length of crack, at the same applied load due to the closure effect of the tensile reinforcement
Summary
Compression field theory (Collins 1978); modified compression field theory, Vecchio and Collins (1986); strut and tie model, Schlaich et al (1987) and the concept of 'compressive-force path' (CFP) Kotsovos (1988) have evolved in the general field of structural concrete design. Most of these methods minutely deviate from the basis on which present-day design is founded; and still carrying implicit assumptions which, in many cases, are incompatible with the fundamental properties of concrete
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
