Structural capacity of reinforced concrete columns with U-shaped transverse bars. (1st August 2020)

• Record Type: Journal Article
• Authors: Hwang, Hyeon-Jong; Noh, Ju-Ok; Park, Hong-Gun
• Is Part Of: Engineering structures. Volume 216(2020)
• Publication Date: 2020-08-01
• Subjects: Reinforced concrete column -- Mega column -- U-shaped transverse bar -- Compression loading test -- Cyclic loading test; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2020.110686
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: New transverse reinforcement detail for better constructability of large columns. Assembled U-shaped tie bars replacing conventional hoops and cross-ties. Compression loading test and cyclic lateral loading test of RC columns. Comparison of structural performance between the columns with the proposed details and conventional hoops and ties. Abstract: In large reinforced concrete (RC) columns for mega columns in high-rise buildings and plants, constructability is deteriorated due to difficulties in assembling long reinforcing bars. In the present study, U-shaped tie bars were studied to improve the constructability of large RC columns by replacing the hoops and cross ties with U-shaped tie bars. The compression loading test and cyclic lateral loading test were performed on RC columns to verify the effect of U-tie bars. For the test parameters, the types of U-tie bars, neutral axis depth of cross-section, and loading types were considered. The test results showed that the strength and deformation capacities of the columns using U-tie bars were comparable to those of the columns using conventional transverse reinforcement. Closely-spaced U-tie bars satisfactorily restrained early local buckling of the longitudinal bars and provided adequate confinement effect to the core concrete, without early failure of the U-bars. Further, design recommendations were discussed to use U-tie bars for transverse reinforcement in large columns.