Synergistic effect on the degradation rate of pultruded glass fiber-reinforced polymer bridge panel after 20 years of exploitation

Abstract

Glass fiber-reinforced polymer pultruded profiles have great potential in the construction industry, presenting certain advantages when compared with traditional materials, including the potentially improved durability under fluctuating levels of environmental factors. The paper presents analysis of glass fiber-reinforced polymer composite, acquired from cable-stayed Fiberline Bridge exploited for 20 years in the fjord area of Kolding, Denmark. Fragment of composite material used for Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis tests was therefore subjected to natural aging as a result of temperature amplitudes, permanent solar radiation as well as aggressive impact of sea salt contained in the moisture in the air around the coastal area. Complex comparative analysis presented in this paper, and based on Fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis tests, pertained to both unspool composite glass fiber-reinforced polymer material (composite 1) and the one after 20 years of natural aging (composite 2). Dynamic mechanical analysis was allowed to detect thermal effects based on the changes in the modulus or damping behavior. The differential scanning calorimetry experiments were performed on the glass fiber-reinforced polymer material in order to determine the mass variation and the energy changes suffered by the materials, as a function of temperature and time.

The resistance to UV radiation for GFRP pultruded bridge panels

“…The combined action of both UV and water on polymers as a function of time and temperature could be even more severe than the individual effects. Most importantly the sums of the individual UV and water condensation aging effects on weight changes are positive with weight gains, whereas the weight changes under the cyclic combined conditions are negative with weight losses for all tested composites [13]. When a polymer is subjected to ultraviolet radiation it releases constituents in the form of thin, loosely adherent dust.…”