电阻率法计算内养护混凝土氯离子扩散系数OA北大核心CSTPCD

Based on the Nernst-Plank equation,the formation factor was introduced to analysis the influence of ion composition and concentration of concrete pore solution on its conductivity,and a chloride ion diffusion coefficient calculation model based on concrete resistivity was established.Through the concrete resistivity test,the influence of water-binder ratio,internal curing effect and curing conditions on the internally cured concrete resistivity and pore tortuosity was discussed,and the chloride diffusion coefficient obtained by ponding test and resistivity test was compared.Results show that the internal curing concrete with low water-binder ratio has greater resistivity and pore tortuosity than that of the ordinary concrete,and the curing condition has less influence on the resistivity and pore tortuosity of concrete;the concrete resistivity can reflect the chloride ion transport performance in concrete to a certain extent,and the chloride ion diffusion coefficient of concrete obtained by the resistivity test has a good linear correlation with the results obtained by ponding test.