The effect of chloride ingress in reinforced geopolymer concrete exposed in the marine environment

Determining the durability of geopolymer materials in a real field environment is important to enhance the feasibility of their use in concrete production.. This paper investigates the durability of slag-based geopolymer concrete (SGPC-M) exposed in the spray/splash zone of the marine environment. Properties of SGPC-M in the marine environment including chloride resistance, absorption characteristics, and the scaling effect were examined and compared with ordinary Portland Cement concrete (OPC-M) properties in the same environment. The test results indicate that the SGPC-M has a lower resistance to chloride penetration than the OPC-M concrete. Compared to the OPC-M, higher values of diffusion coefficient and lower values of chloride binding capacity were obtained for the SGPC-M concrete. Besides, the study on the pore characteristics and absorption behaviour of the concrete indicates that the SGPC-M possesses more pores than the OPC-M, which is related to the lower resistance to chloride penetration in the marine environment. Furthermore, the microstructural changes due to chloride attack in the SGPC-M are different than the changes in the OPC-M concrete, which was identified from the SEM and XRD analysis.

Automated summary

This paper investigates the durability of slag-based geopolymer concrete in the marine environment and finds that it has lower resistance to chloride penetration compared to ordinary Portland Cement concrete. The study also shows that the microstructural changes due to chloride attack in the geopolymer concrete differ from those in the OPC concrete.