Modeling of the strut-and-tie parameters of deep beams for shear strength prediction

A generally accepted rational model to predict the shear strength of a structural member needs to satisfy Navier's three principles (force equilibrium, strain compatibility, and constitutive equations). However, a shear model satisfying these three principles usually requires rigorous computational effort. This study reveals that, if involved structural parameters are properly considered, a simple strut-and-tie model that merely satisfies force equilibrium can give similar accuracy compared to the sophisticated strain compatible model. This finding was verified against 118 deep beam specimens tested in the laboratory. The important structural parameters identified are the definition of a shear element that is consistent with force discontinuity, the consideration of elastic behavior in estimating the width of a strut, the dimensions of a nodal zone influenced by a loading plate, and the proper selection of the probable failure modes. (C) 2015 Elsevier Ltd. All rights reserved.