A New Refined Truss Modeling for Shear-Critical RC Members (Part I) - lts derivation of Basic Concept -

- Journal title : Journal of the Korea Concrete Institute
- Volume 16, Issue 6, 2004, pp.785-794
- Publisher : Korea Concrete Institute
- DOI : 10.4334/JKCI.2004.16.6.785

Title & Authors

A New Refined Truss Modeling for Shear-Critical RC Members (Part I) - lts derivation of Basic Concept -

Kim Woo; Jeong Jae-Pyong; Kim Dae-Joong;

Kim Woo; Jeong Jae-Pyong; Kim Dae-Joong;

Abstract

This paper describes a new refined truss modeling technique derived based on the well-known relationship of V=dM/dx=zdT/dx+Tdz/dx in a reinforced concrete beam subjected to combined shear and moment loads. The core of the model is that a new perspective on the shear behavior can be gained by considering the variation of the internal arm length along the span, so that the shear resistance mechanism can be expressed by the sum of two base components; arch action and beam action. The sharing ratio of these two actions is determined by accounting for the compatibility of deformation associated to the two actions. Modified Compression Field Theory and the tension-stiffening effect formula in CEB/FIP MC-90 are employed in calculating the deformations. Then the base equation of V=dM/dx has been numerically duplicated to form a new refined truss model.

Keywords

arch action;arch factor;beams;reinforced concrete;truss model;

Language

Korean

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