Contents lists available at ScienceDirect Structures journal homepage: www.elsevier.com/locate/structures Manufacturing and structural performance of glass-fiber-reinforced precast- concrete boat ramp planks A.C. Manalo a, ⁎ , O. Alajarmeh a , D. Cooper a , C.D. Sorbello b , S.Z. Weerakoon b , B. Benmokrane c a Centre for Future Materials (CFM), School of Civil Engineering and Surveying, University of Southern Queensland, Toowoomba 4350, Australia b Boating Infrastructure Unit, Department of Transport and Main Roads, Brisbane City 4000, Australia c University of Sherbrooke, Department of Civil Engineering, Sherbrooke, Quebec, Canada ARTICLE INFO Keywords: Boat ramp planks Glass-fiber-reinforced polymer (GFRP) bars Manufacturing Time-and-motion study Structural performance Optimised design ABSTRACT Glass-fiber-reinforced-polymer (GFRP) bars are an ideal solution for eliminating the problems of steel corrosion in reinforced-concrete structures exposed to marine environments. The potential long-term benefits of the re- duced maintenance costs and increased service life of GFRP-reinforced concrete structures have not been fully realized due to these reinforcing materials being more costly than steel bars. This study aims to demonstrate the cost-effectiveness of GFRP bars as internal reinforcement in precast-concrete boat-ramp planks. This is the first study that provided a comparative evaluation of the manufacturing and structural performance of planks re- inforced with GFRP bars or galvanized-steel bars to fully convince engineers and asset owners of the economic benefits of specifying and using GFRP bars in infrastructure projects. The results of the study revealed that the fabrication and installation of the reinforcing mesh constituted the main differences between planks reinforced with GFRP or galvanized steel. Overall, fabricating precast-concrete boat-ramp planks with two layers of GFRP bars required less labor and equipment, and yielded better serviceability and structural performance than the current plank design using galvanized steel. These benefits led to approval and publication of the standard drawings for a new plank design for implementation in boating-infrastructure projects in Australia. 1. Introduction In Australia, precast reinforced-concrete (RC) planks are used as platforms for recreational boat ramps [1]. Unfortunately, corrosion of the internal steel reinforcement causes the planks to deteriorate. Ac- cording to the Queensland Department of Transport and Main Roads (DTMR), precast-concrete members for use in marine infrastructure should be designed based on a minimum exposure classification of A2 [2] and a minimum service life of 50 years [3]. A study conducted by Mehta et al. [4], however, concluded that the service life of RC struc- tures in aggressive environments, such as those located in or near marine areas, is only between 20 and 30 years due to steel corrosion. Austroads [5] conducted a recent review yielding similar conclusions in that they observed that most of the concrete structures designed to have a service life of 100 years started to deteriorate only after 30 years, especially those structures built in aggressive environments. In Queensland, the economic loss associated with the expenditures for the repair, rehabilitation, and maintenance of corrosion-damaged boating infrastructure amounts to AUD$10 million annually [6]. Steel corrosion costs the Australian economy more than AUD$13 billion per year [7]. Yalciner et al. [8], Mehta [9], and Cabral et al. [10] recommended different anti-corrosion design methods, including increasing the re- inforcement concrete cover, installing cathodic protection, using high- performance concrete mixes, and opting for corrosion-resistant mate- rials such as galvanized, epoxy-coated, or stainless-steel reinforcement. These methods are only temporary solutions or simply too impractical and expensive to implement and operate. Moreover, the use of these various techniques has not completely eliminated the deterioration of steel reinforcement [11]. As a result, Engineers Australia [12] has been calling for a new approach and construction technologies promising long-term solutions due to the limited resources of the state and federal governments for maintaining existing infrastructure. The use of composite materials have been explored by many re- searchers to improve the cost-effectiveness of civil structures [13–15]. https://doi.org/10.1016/j.istruc.2020.08.041 Received 29 March 2020; Received in revised form 30 June 2020; Accepted 13 August 2020 ⁎ Corresponding author at: Centre for Future Materials (CFM), School of Civil Engineering and Surveying, University of Southern Queensland, Toowoomba 4350, Australia. E-mail addresses: manalo@usq.edu.au (A.C. Manalo), Omar.Alajarmeh@usq.edu.au (O. Alajarmeh), u1069746@umail.usq.edu.au (D. Cooper), Charles-Dean.A.Sorbello@tmr.qld.gov.au (C.D. Sorbello), Senarath.Z.Weerakoon@tmr.qld.gov.au (S.Z. Weerakoon), Brahim.Benmokrane@USherbrooke.ca (B. Benmokrane). Structures 28 (2020) 37–56 2352-0124/ © 2020 Institution of Structural Engineers. Published by Elsevier Ltd. All rights reserved. T