Experimental investigation on the behavior of corroded CHST columns retrofitted using AFRP

Abstract

The paper presents an experimental investigation using Aramid Fibre Reinforced Polymer (AFRP) composites on the retrofitting of corroded Circular Hollow Steel Tubular (CHST) column under axial compression. So far, the experimental investigation was limited to the use of FRP such as Glass Fibre Reinforced Polymer (GFRP) and Carbon Fibre Reinforced Polymer (CFRP) and also the way of application of FRP on the structure, i.e., the wrapping system. A study for the expediency of AFRP fabrics in the axial strengthening of CHST columns was done in this paper. The disadvantage of AFRP is the cost alone, so the full wrapping of the CHST sections with AFRP will be pricey. The assets of AFRP over steel structures are the low weight, ease in application and with a limited approach it can cover a maximum area. Total ten samples were tested including control and wrapped specimen in various techniques until the failure mode. The results obtained from different experiments were compared with the control sample and later the load-deflection and stress-strain properties were studied. The results from the experimental investigation admitted that, the external wrapping of AFRP fabric strips undoubtedly build up the load carrying amplitude of the CHST columns. The increase in the number of the layers of AFRP strips also effectively deferred the local buckling of the CHST columns by increasing the vertical displacement.