Effect of Inclination of Rectangular Reinforced Concrete Short Columns on the Confinement

Sayhood, Eyad K.; Muhammed, Bassman R.; Hatem, Ahmed A.

doi:10.30684/etj.v39i12.437

	Effect of Inclination of Rectangular Reinforced Concrete Short Columns on the Confinement
Engineering and Technology Journal
Article 11, Volume 39, Issue 12, 2021, Pages 1821-1827 PDF (760.05 K)
Document Type: Research Paper
DOI: 10.30684/etj.v39i12.437
Authors
Eyad K. Sayhood^* ; Bassman R. Muhammed; Ahmed A. Hatem
Civil Engineering Department,University of Technology-Iraq, Alsina’a street, P.O BOX 10066 Baghdad, Iraq.
Abstract
The main objective of this paper is to study the confinement of the rectangular reinforced concrete short inclined columns. This paper was based on theoretical analysis using the MATLAB program according to Universal Codes, and variables that were carefully selected to be the most influential factor. The angle of the inclination (α) was taken as a major variable in the paper, in addition other variables which in turn affect directly on the behavior of inclined columns such as the percentage of reinforcing steel in the concrete section of the column (ρ), the compressive strength of the concrete (fʹc), yield strength of steel bars (fy) and effective depth ratio (γ). The results show that best ratio of reinforcing steel that improves the value of the confinement ranges from 0.4 - 0.6 which leads to an increase in the confinement of (60 – 100) %, and these rates increase with increasing α, and the increase in fʹc leads to a significant increase in the confinement, especially when HSC is used..On the other hand, decreasing fy leads to increase in confinement, and the value of the γ had a considerable effect on the confinement that was decreased by about 11% when γ equals 0.9, compared with the corresponding γ equals 0.6.
Highlights
The inclination effect on the concrete column decrease confinement. There are certain angles that we can adopt in the design of inclined columns to avoid reducing confinement. The use of high strength concrete contributes greatly to avoiding the reduction of confinement in the inclined columns.
Keywords
Confinement; Angle of the inclination; compressive strength; Effective depth ratio; Yield strength of steel bars

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