Effect of different anchorage schemes on the flexural behavior of RC slabs strengthened with CFRP sheets

Abstract

This research investigated the behavior of RC slabs subjected to four points loading with five different CFRP sheet numbers (1, 2, 3, 4, 5) and three different anchorage systems (Type 1 used CFRP strips in the transverse direction, Type 2 used galvanized steel end plates without grooving, Type 3 used galvanized steel end plates with grooving). A total of twenty reinforced concrete (RC) solid slabs were cast to fulfill the study objectives. Results showed that the presence of CFRP strips enhanced the slab's ultimate load capacity by 102 %, reduced mid-span deflection by 12 %, also improved energy absorption capacity and stiffness by 36 % and 32 %, respectively. Type 2 anchorage system without grooves and type 3 anchorage system with grooves both used galvanized steel end plates and enhanced the flexural capacity of the slabs by 119 % and 125 %, respectively, also improved the RC slab properties and shifted the failure mode from delamination to a CFRP strips rupture. The introduced anchorage system without grooving was found to be an efficient and easily applied technique with high efficiency in terms of capacity and serviceability.