Life-cycle study of concrete bridges strengthened with carbon-fibre-reinforced polymer

Abstract

China has many bridges in a vulnerable condition, and strengthening is crucial to guarantee their service life and performance. However, environmental impact is rarely considered in the maintenance of reinforced concrete structures. Moreover, considering the effects of vehicle overload and the external environment remains difficult. To solve these problems, the life-cycle reliability and induced environmental impact of strengthening bridges with bonded carbon-fibre-reinforced polymer under different external environmental conditions and overload scenarios were studied using Monte Carlo sampling, first-order second moment and life-cycle assessment methods. A simply supported reinforced concrete T-beam was selected as a case study. The results indicated that the external environmental conditions contributed significantly to the polymer strengthening effect, and polymer plates contributed more to reliability than polymer fabric. In overload scenarios, plates were more suitable for strengthening than fabric. When annual environmental impacts were considered over time, life-cycle maintenance plans with plates were better than with fabric, and environmental impacts were sensitive to the discount rate.