Environmental assessment of concrete beams strengthened with fibre-reinforced polymer
As concerns grow over sustainable development, it is important to consider properly the environmental implications of using fibre-reinforced polymers to strengthen concrete structures. Since the load capacity of a structure has an effect on its relative environmental impact, an energy–mechanical index, in which both energy consumption and mechanical aspects are taken into account, was proposed for evaluating the integrated environmental performance of strengthening solutions. Life-cycle assessment was used to evaluate the energy use, and corresponding experiments were designed to obtain the load capacity of reinforced concrete beams with different strengthening solutions. Moreover, Monte Carlo simulation was adopted to analyse the parameter uncertainty of the life-cycle assessment. The strengthening experiments indicated that the carbon-fibre-reinforced-polymer strengthening solution had a more efficient improvement impact on load capacity compared with the basalt-fibre-reinforced-polymer solutions. The improvement with one carbon-fibre sheet was equivalent to that with two basalt-fibre sheets. However, the carbon-fibre strengthening solution consumed more energy than the basalt-fibre strengthening solutions due to its high embodied energy. In addition, the energy–mechanical index of the basalt-fibre strengthened beams was far lower than that of the carbon fibre ones, whether the determined approach or the probability-based method was adopted, indicating the superior integrated performance of the basalt-fibre-reinforced-polymer strengthening solution.