非饱和硬化水泥浆氯离子扩散性能的数值模拟

基于固相分形模型和格子Boltzmann方法,通过数值模拟手段研究非饱和硬化水泥浆的氯离子扩散性能.首先应用固相分形模型来模拟硬化水泥浆的多孔结构,在此基础上采用格子Boltzmann方法模拟相应的氯离子扩散.在固相分形模型中,按照孔隙尺寸分布对硬化水泥浆多孔结构进行逐级饱和来实现饱和度的变化.对比当前数值模拟的结果与经典幂函数型饱和函数的预测结果,发现二者吻合较好,饱和系数的合理取值为4~5.

Numerical Simulation of Chloride Diffusivity in Non saturated Hardened Cement Paste

Numerical simulation was performed on chloride diffusivity in non saturated hardened cement paste, in which saturation function was related to saturation degree. In particular, the solid mass fractal model was applied to simulate pore structure of hardened cement paste. Meanwhile, the lattice Boltzmann method was applied to simulate chloride diffusion. The variation of saturation degree was addressed in terms of the successive filling of pores with respect to pore size distribution. The present numerical results agreed well with the results calculated from classical power type saturation function, and the saturation coefficient should be of 45.