Title:
Reinforced Concrete Flanged Beams--Test and Analysis
Author(s):
N. K. Subedi
Publication:
Structural Journal
Volume:
90
Issue:
6
Appears on pages(s):
601-615
Keywords:
beams (supports); biaxial loads; deformations; diagonal tension; failure; flanges; loads (forces); reinforced concrete; stiffness; stresses; webs (supports); Structural Research
DOI:
10.14359/4457
Date:
11/1/1993
Abstract:
Slender and thin-walled forms of construction are a natural choice for large-scale structures employing reinforced concrete. Reinforced concrete flanged beams provide structural strength and stability whose applications range from buildings, offshore structures, and flotation units for housing in marshy land to floating hotels. Tests were carried out on 20 reinforced concrete flanged beams with overall depth/web thickness ratio between 40 and 80. The test specimens were mostly large structural elements, some of which measured 2 x 4 m overall. The web thickness ranged from 20 to 33 mm. The test specimens represented some of the most slender forms of reinforced concrete construction attempted in a laboratory. The main modes of failure observed in the test were flexure, diagonal splitting, and web crushing. The characteristics of the modes of failure and the mechanisms are discussed. Web crushing mode of failure happens suddenly and can be dangerous. Diagonal and flexural shear modes of failure are governed by the limiting tensile strength of concrete in biaxial compression-tension state of stress. Web crushing mode is governed by the compressive strength of concrete. Two methods of analysis are presented in this paper. Method A is based on the failure of the structure due to the splitting action of the thin web in tension. Method B is based on the failure due to the crushing of the web in compression. The analysis results are compared with the test results.