Effects of Short-Term Environmental Exposure on Axial Strengthening Capacity of Composite Jacketed Concrete
Abstract
Recent studies from the U.S. Department of Transportation (USDOT) estimate that of the 575 000 bridges in the nation, 230 000 (or 40%) are either structurally deficient or functionally obsolete. The deterioration has been caused by a variety of factors including corrosion due to marine environments, high chloride content in the air and use of de-icing salts, alkali-silica reactions (ASR), environmental effects on materials, poor initial design, and poor construction and maintenance, or both. Cracking and spalling of concrete columns is often seen with corrosion of internal reinforcement steel due to moisture and chloride ingress. The loss of cementitious material, as well as the reduction in steel cross-section, leads to drastic reductions in the structural efficiency and load-carrying capacity of columnar supporting elements. The high stiffness-to-weight and strength-to-weight ratios of advanced composites, combined with their inherent corrosion resistance, environmental durability, and tailorability make them attractive for use in infrastructure renewal. In this paper, we investigate the effect of environmental exposure on the strengthening efficiency of composite-jacketed concrete column stubs. The effects of short-term exposure to ambient and 0°F conditions as well as to water and sea water on glass-, carbon-, and aramid-epoxy jackets is investigated.