Title: Compatibility Strut-and-Tie Modeling: Part I—Formulation

Author(s): Reece M. Scott, John B. Mander, and Joseph M. Bracci

Publication: Structural Journal

Volume: 109

Issue: 5

Appears on pages(s): 635-644

Keywords: D-region; deep beams; deformation compatibility; shear; strut-and-tie; truss model

DOI: 10.14359/51684041

Date: 9/1/2012

Abstract:
A compatibility-based strut-and-tie model (C-STM) intended for analyzing the nonlinear force-deformation behavior of disturbed regions and structural concrete deep beams is presented. In addition to the normal strut-and-tie force equilibrium requirements, the proposed C-STM accounts for nonlinear behavior using nonlinear constitutive relations for cracked reinforced concrete. The model is implemented using commercially available structural analysis software, SAP2000. To assess C-STM accuracy, convergence studies using different truss representations are explored. Particular emphasis is placed on investigating the behavior of deep cantilevered beams to provide insight into the progression of nonlinear response leading to the ultimate shear failure. New developments for modeling the nonlinear behavior of concrete compression chord members and compression-softening effects of diagonal concrete struts are proposed. The implementation is presented in the companion paper.