An approach to improve conventional square ferrocement jacket for strengthening application of short square RC column
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The confinement effect over the cross-section of a square column is non-uniform compared to the same of a circular column. Concentration of stresses and subsequent cracking in the confining external jacket occurs at the corners of a square column; and thus the effectiveness of external jacket in such column is reduced significantly. The conventional square ferrocement jacket consists of rich mix cement mortar with single or multiple layers of wire mesh. This type of external jacket also experience similar problems in confining core columns. This study aims to develop efficient techniques to overcome the drawbacks of conventional square ferrocement jackets in strengthening of short square-shaped RC columns. Three techniques and variations in those techniques are proposed to address the problem. Experimental studies of selected variation from each technique affirm the effectiveness of the proposed techniques in addressing the problem associated with conventional square ferrocement jackets. The experimental investigation reveals that all the retrofitted square ferrocement-jacketed short columns exhibit higher load carrying and deflection capacities before failure compared with non-jacketed as well as conventional square ferrocement-jacketed columns. The findings indicated that the proposed techniques are efficacious to address the problem of conventional square ferrocement jacket.
KeywordsStrengthening Ferrocement jacket Square RC column Stress concentrations Stress transfer
The authors acknowledge the financial support provided by the Ministry of Higher Education of Malaysia through the ERGS grant scheme (ERGS/1/2011/TK/UKM/02/10). In addition, the first author would like to extend his gratitude to UKM for the financial support it provided through the Research University Zamalah Scholarship.
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