关键词: 混凝土, 弯曲荷载, 腐蚀介质, 硫酸根离子, 氯离子, 离子分布

Abstract:

The stress magnitude and state in different part of concrete specimen under flexural load were analyzed,and the distribution regularity of corrosive media SO^2₄- and Cl^- in concrete was also investigated.The results showthat (1) in the concrete layers with the same diffusion distance,SSO^2₄- and Cl^- contents in pure bending area arehigher than those in flexural shear area; (2) SO^2₄- and Cl^- contents in tensile stress layer are higher than that incompressive stress layer; (3) the most severely- damaged part of concrete specimen under flexural load locates atthe tensile stress layer of pure bending area,with the corresponding SO^2₄- and Cl^- contents achieving the maxi-mum; (4) the loading not only enhances the permeability but also changes the distribution regularity of SO^2₄- and Cl^- in concrete.Specifically,the ion content distribution,which is different from the symmetrical style in concretewithout loading,presents a √- shaped style from the compressive stress surface layer to the tensile stress surfacelayer,with the bottom appearing in the third layer or the fourth middle layer and the top occurring in the tensilestress surface layer.

Key words: concrete, flexural load, corrosion medium, ion distribution, sulfate ion, chloridion, ion distribution