Research Article Behavior and Performance of GFRP Reinforced Concrete Columns with Various Types of Stirrups Woraphot Prachasaree, 1 Sitthichai Piriyakootorn, 1 Athawit Sangsrijun, 2 and Suchart Limkatanyu 1 1 Department of Civil Engineering, Faculty of Engineering, Prince of Songkla University, Hat Yai, Songkhla 90112, hailand 2 Program in Landscape Technology, Faculty of Agricultural Technology, Rajamangala University of Technology hanyaburi, hanyaburi, Pathum hani 12110, hailand Correspondence should be addressed to Woraphot Prachasaree; pworaphot@eng.psu.ac.th Received 2 August 2015; Revised 5 September 2015; Accepted 9 September 2015 Academic Editor: Jo˜ ao M. L. Dos Reis Copyright © 2015 Woraphot Prachasaree et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Fiber reinforced polymer (FRP) composites are gaining acceptance in concrete structural applications due to their high ratio of strength/stifness to self-weight and corrosion resistance. his study focused on the structural behavior and the performance of concrete columns internally reinforced with glass iber reinforced plastic (GFRP) rebars. Twelve series of concrete columns with varied longitudinal reinforcement, cross section, concrete cover, and type of lateral reinforcement were tested under compression loading. he results show that the amount of GFRP longitudinal and lateral reinforcement slightly afects the column strength. he lateral reinforcement afects the conining pressure and inelastic deformation, and its contribution to the conined compressive strength increases with the GFRP reinforcement ratio. In addition, the conining pressure increases both concrete strength and deformability in the inelastic range. he coninement efectiveness coeicient varied from 3.0 to 7.0 with longitudinal reinforcement. he average deformability factors were 4.2 and 2.8 with spirals and ties, respectively. Lateral reinforcement had a more pronounced efect on deformability than on column strength. 1. Introduction In general, concrete structures with conventional steel rein- forcement have about 50 years of service life in an aggressive environment, such as in infrastructure highways and bridges with exposure to deicing salts, in marine structures, in waste water facilities, and in chemical treatment plants. In such conditions the corrosion of steel reinforcement leads to deterioration of the concrete structures and to loss of service- ability. his deterioration is one of the most serious problems in civil and infrastructural engineering. Such facilities incur tremendous repair costs annually. he replacement of steel with noncorroding materials, such as iber reinforced plastics (FRPs), could be efective in alleviating these problems. he structural conditions of infrastructures would require long-term durability and a high degree of performance. In reinforced concrete columns, epoxy-coated steel rebars have been used as a corrosion resistant alternative. However, this approach has its limitations because of the costs and the delayed but eventual susceptibility to corrosion. In the past decade, studies have been published on the performance and behavior of concrete structural members internally rein- forced with FRPs. Fourteen concrete beam columns inter- nally reinforced with glass iber reinforced plastic (GFRP) rebars were experimentally investigated under compression and bending in [1]. he results showed that the maximum capacity of GFRP reinforcing rebars could only reach 70% of their tensile strength in pure lexure and 20–30% of ulti- mate compressive strength under axial compression. Twelve concrete columns reinforced with aramid iber reinforced plastic (AFRP) rebars were tested under eccentric applied tension or compression [2]. It was concluded that the analysis methods for steel reinforced concrete columns were appro- priate also for concrete columns reinforced with AFRP rebars. Hindawi Publishing Corporation International Journal of Polymer Science Volume 2015, Article ID 237231, 9 pages http://dx.doi.org/10.1155/2015/237231