Introduction
Precast concrete garages are usually made up of a system of conventionally reinforced precast concrete column, slabs, beams, and girders. Parking garages are subject to more deterioration than most of the concrete members. The use of deicing salts during the winter triggers and accelerates the deterioration process in such structures. Reinforcing steel corrosion and perpetual concrete deterioration can weaken structural members due to loss of effective concrete cross section, reinforcement cross section, and connection failure. Replacing corrodible steel with corrosion-free FRP composites is the only practical and cost effective solution for eliminating the potential risk of corrosion and degradation.
GFRP reinforcement
Glass fiber-reinforced polymer (GFRP) reinforcement has demonstrated great potential for integration into the parking, transportation, and waterside concrete infrastructure. Fiberglass materials have long and useful lives. They offer solid resistance against corrosion, ease of construction, excellent strength-to-weight characteristics, and custom fabrication in terms of strength, stiffness, geometry, and other properties. This is the reason why GFRP reinforcement is being widely accepted as a viable solution to corrosion related problems in concrete members.
The blog post will analyze a case study: “Design, construction, and performance of the La Chanceliere parking garage’s concrete flat slabs reinforced with GFRP bars”, in order to understand the role of modern construction materials (GFRP bars) in building sustainable and maintenance-free parking garages.
La Chanceliere Parking Garage Quebec, Canada
La Chanceliere Garage was a 40-year-old concrete structure which needed to be rehabilitated following the severe corrosion of steel reinforcement in most of the slabs. The authorities decided to rehabilitate the structure by replacing structure’s flat slabs while maintaining the columns and retaining walls. After a careful evaluation and cost analysis of both steel and GFRP reinforcing bars, authorities decided to go with GFRP fiberglass bars for this project. According to the case study, it was the first parking garage rehabilitation project reinforced completely with GFRP rebar.
Findings
The performance of the completed project revealed that the decision to select GFRP reinforcement was absolutely right. Based on the in-service results and insights, it can be concluded that:
- The GFRP rebar offered an economically viable solution to counter corrosion related issues in the RC parking garage structure.
- It was seamless to implement GFRP bars and complete the project on time without facing any obstacles. The installation of GFRP bars and adhesive anchors was performed with great ease.
- Over the last three and a half year, the RC flat slabs demonstrated normal performance so far as strain and cracking are concerned.
- The construction process was carried out in compliance with the CSA 2012 design provisions, strength and serviceability criteria.
- The cost analysis of the project showed that the GFRP reinforcement was a cost effective and dependable construction solution.
- Following the continuous observation and monitoring, it was concluded that GFRP bars performed as anticipated.
- The project clearly reflected the properties of advanced composites and how these modern materials can help civil engineers build sustainable and long lasting parking garages.
The existing GFRP-reinforced concrete structures clearly demonstrate the unique properties of FRP composites and their application in civil engineering. FRP composite materials are very effective against the harsh environment and corrosive agents. A concrete structure that can successfully withstand severe environment achieves a long service life without any major maintenance or repair. Parking garages and other sensitive concrete structures, therefore, should be built and rehabilitated with GFRP reinforcement.
