摘要
为了研究聚丙烯纤维混凝土中硫酸盐的扩散过程,首先根据聚丙烯纤维在混凝土中的空间分布特征,将其空间分布分为贯通型、半贯通型和内嵌型3种类型,分别计算了3种类型聚丙烯纤维对孔隙率的影响规律,然后基于Fick第二定律及反应动力学方程,建立了硫酸根离子在聚丙烯纤维混凝土中的扩散模型,并采用有限差分法进行数值求解,实现了对任意位置处硫酸根离子浓度的数值求解;最后采用聚丙烯纤维混凝土硫酸盐侵蚀试验对数值模拟结果进行对比验证。结果表明,数值计算结果与实际试验结果相对误差不超过17.65%,精度较高。
In order to study the diffusion process of sulfate in polypropylene fiber concrete.Firstly,according to the spatial distribution characteristics of polypropylene fibers in concrete,the spatial distribution was divided into three types,and they were through type,semi-through type and embedded type,and the influence of three types of polypropylene fibers on the porosity was calculated.Then,based on Fick's second law and reaction kinetics equation,the diffusion model of sulfate ion in polypropylene fiber concrete was established.And the finite difference method was used to solve the numerical solution of the concentration of sulfate ions at any position.Finally,the numerical simulation results of polypropylene fiber reinforced concrete sulfate erosion test were compared.The results show that the relative error between the numerical results and the actual experimental results is not more than 17.65%,so the accuracy is high.
引文
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