Experimental investigation on short concrete columns laterally strengthened with ferrocement and CFRP

The use of ferrocement in strengthening reinforced concrete (RC) structures has increased recently. Ferrocement has mostly been used to provide extra confinement for RC columns. However, its performance, especially in combination with CFRP confinement has not yet been fully understood. In this study, a total of fifteen columns were experimentally tested to investigate the effects of using ferrocement confinement in strengthening square RC columns. The combination between CFRP and ferrocement in strengthening RC columns has also been investigated. In addition to providing extra confinement, ferrocement is used to modify the shape of square columns to curvilinear shape, which is more effective for confinement. The parameters were (1) the materials used for confinement (ferrocement, CFRP, or both), (2) cross-sectional shape (square, curvilinear, or circular), and (3) the amount of confinement (full vs. partial confinement). The results show that ferrocement is very effective if combined with CFRP. The curvilinear shape provided by ferrocement helps to distribute the lateral stresses and ultimately reduces stress concentration which is usually the cause of failure for columns strengthened with CFRP confinement. The results are analyzed and discussed, and a number of conclusions are presented.