Improved ferrocement jacketing for restrengthening of square RC short column

Abstract Conventional square ferrocement jacketing (square jacketing with single or multiple layers wire mesh) cannot provide lateral confinement effectively in restrengthening of square RC column due to stresses concentration at the column corners. Therefore, improvement of conventional square ferrocement jacketing technique is focused in this study. Three new square ferrocement jacketing techniques such as square jacketing with single layer wire mesh and rounded column corners (RSL); square jacketing using single layer wire mesh with shear keys at the center of each face of column (SKSL) and square jacketing with single layer wire mesh and two extra layers mesh at each corner (SLTL) are considered for this purpose. Entire study was carried out experimentally. A total number of 41 scaled down non-jacketed and ferrocement jacketed column specimens were tested under both concentric and eccentric modes of loading. Test results and the crack patterns of tested specimens show that all three improved square ferrocement jacketing techniques are effective to overcome the stress concentration problem of conventional square ferrocement jacketing. Among all jacketing techniques considered in this study SLTL type jacketing shows the best performance in carrying concentric loading, however, in case of eccentric loading, best performance is found in RSL type ferrocement jacketing.

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