Modeling of shear deficient beams by the mixed smeared/discrete cracking approach

This paper presents an analytical study on the modeling of shear critical reinforced concrete beams modeled using the finite element method. The paper investigates two modeling strategies; the first of which is the well established smeared cracking modeling approach. Experimental test results from a wide range of beams tested by other researchers were used for model verification. This paper presents a mixed modeling approach in which the smeared cracking model was used in conjunction with discrete cracking planes to model the concrete continuums in an effort to reach a better correlation with the experimental data. This is achieved by introducing a specific plane inclined at angles in a specified range determined as a result of matching these models’ behavior with behavior monitored in the experimental work at the suspected plane of failure for shear critical beams. Analytical results have shown that the proposed modeling approach is capable of better simulation of the observed experimental response in terms of strength and stiffness, as well as capturing the post-peak response of the tested beams. Errors have been calculated between analytical and experimental results; these errors are also acceptable within the bounds of the engineering judgment. Finally the mixed smeared/discrete cracking model is validated and can be used with a high degree of confidence to conduct further parametric studies.