DURABILITY OF GLASS FRP COMPOSITE BARS FOR CONCRETE STRUCTURE REINFORCEMENT UNDER TENSILE SUSTAINED LOAD IN WET AND ALKALINE ENVIRONMENTS

摘要

This paper describes a new experimental set-up specially designed for accelerated ageingtests for Fibre-Reinforced Polymer (FRP) reinforcements. The set-up uses a combination of temperature,environmental exposure (alkaline, saline, water, and concrete), and tensile sustained loads. Two seriestestsI and II of Glass Fibre-Reinforced Polymer (GFRP) bars 12.7 mm-diameter were exposed to twodifferent environments, namely the alkaline solution and de-ionized water, respectively. Temperaturevarying between 45 to 63°C is used to accelerate the degradation mechanism. Also, the bars weresubmitted to sustained tensile loads varying from 20 to 29 % of the short-term ultimate tensile strength.Both series specimens were exposed for a 104 days (15 weeks) duration. Following the acceleratedageing tests, the GFRP specimens were removed and tested for residual tensile strength. Results ofthese residual tensile tests are reported in this paper and compared to the guaranteed tensile and designstrengths of the GFRP bar used in this experimental investigation.