Compressive Behaviors of Concrete Stub Columns with SFRCC Jacket under Cold-Region Marine Environments

Abstract

The harsh marine environment in cold regions challenges the durability of concrete columns in offshore structures. In this study, a steel fiber-reinforced cement-based composite (SFRCC) jacket is proposed to strengthen concrete columns in cold coastal regions. A total of 147 normal weight concrete columns with SFRCC jackets were prepared to examine the compressive behavior after exposure to three typical marine environments: freeze–thaw cycles, wet–dry cycles, and seawater immersion. The investigated parameters include the duration of exposure to marine environments, the specimen shape, and the thickness of the SFRCC jacket. The influence of these parameters on the compressive behavior of normal weight concrete columns with SFRCC jackets was analyzed and discussed. The test results indicate that introducing SFRCC jackets to concrete columns significantly increases compressive strength. In a marine environment, the SFRCC jacket also proved to be an effective strengthening method in terms of residual strength. The compressive strength of normal weight concrete columns with SFRCC jackets after exposure was predicted using a confinement model with a modification factor to incorporate environmental effects. The accuracy of the proposed equation was confirmed by validating predicted values against test results.