Calculating model for gas diffusivity in concrete

Gas diffusivity in concrete is an important factor for researching concrete carbonation and reinforcement corrosion.Based on the mechanism of gas diffusion,factors that influence gas diffusion in concrete are analysed.After judging existent gas diffusion coefficient calculating formulas,an effective diffusivity calculating model which take concrete compressive strength as main factor are braught forward and influences of environment temperature and relative humidity and the stress state and level of the concrete are considered,and existent experiment results are used to gain model parameters.Consequently,the foundation for forecasting the speed of concrete carbonation and reinforcement corrosion scientifically is established.