Time-varying behavior and its coupling effects with environmental conditions and cementitious material types on surface chloride concentration of marine concrete

Abstract

A time-varying multi-factor model for surface chloride concentration (Cs) of marine concrete was developed by adopting reciprocal function and taking into consideration the coupling effects of exposure duration with cementitious material types and environmental conditions. Firstly, a total of 1385 sets of field test data for Cs of marine concrete under different environmental conditions (i.e., tidal, splash, submerged and atmosphere zones) were collected from 17 countries. Then the reciprocal function was adopted to describe the time-varying behavior of Cs based on detailed comparison with different types of time-varying function. Furthermore, two coefficients were introduced to account for the coupling effects of exposure duration with cementitious material types and environmental conditions on Cs of marine concrete. Subsequently, a time-varying multi-factor model in terms of reciprocal function was developed for Cs of marine concrete under different environmental conditions. Finally, comparison with several different models for Cs was conducted to validate the proposed model. Results show that the proposed time-varying model for Cs accounts for the coupling effects of exposure duration with cementitious material types and environmental conditions, and has high accuracy and general validity.