Formulation of Optimal Strut-and-Tie Models in Design of Reinforced Concrete Structures

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Formulation of Optimal Strut-and-Tie Models in Design of Reinforced Concrete Structures

Author(s): M. A. Ali and R. N. White

Publication: Special Publication

Volume: 193

Issue:

Appears on pages(s): 979-998

Keywords: beam; concrete (reinf orced); strut; tie

Date: 8/1/2000

Abstract:
A new design capability for automated formulation of optimal truss models (strut-and-tie models) is presented and illustrated with example designs of a variety of disturbed regions of reinforced and pre-stressed concrete structures, including deep beams with holes, continuous beams, and comer joints. The design method selects the optimal geometry of the strut-and-tie layout, determining the proper positioning of tensile ties and compressive struts to minimize the amount of reinforcing steel needed in the tension ties of the truss model for the region being designed. Two practical parameters are under control of the design engineer running the computer program-a reinforcement layout practicality factor which can be used to force the reinforcement layout into strictly horizontal and vertical bars (which will require additional reinforcement volume beyond the true optimal value), and a stress redistribution factor which can be used to control the amount of redistribution needed in developing the full capacity of the truss model after cracking has occurred.