An investigation of inorganic fillers on rheological properties and tensile strength of epoxy repair coating using mixture design method

In the process of repairing concrete structures with epoxy coatings, fillers are added for modification so that the coating has sagging resistance and good mechanical properties. This requires comprehensive material design. In this paper, three inorganic fillers (cement, bentonite, and talc) were used to study the effect of fillers on the rheological properties (viscosity, thixotropy) and tensile strength of epoxy coatings through a mixture design method. A multiple linear regression model was established, and the optimal epoxy coating mix was finally obtained. The results showed that the increase of cement content was negatively related to the thixotropy of epoxy coating, but it promoted the tensile strength of the coating. On the contrary, bentonite had a positive effect on the thixotropy of the coating and a negative effect on the tensile strength of the coating. In terms of the shear thinning index, an increase of 1% of the bentonite content can increase the shear thinning index by 1.85 times. Finally, the proportion range of epoxy repair coating that meets the actual engineering needs was obtained through multiple optimization.

Automated summary

This study investigated the effect of different fillers on the rheological properties and tensile strength of epoxy coatings, established a multiple linear regression model, and obtained the optimal coating formulation. The results showed that different fillers have different effects on the coating properties, which can be adjusted according to specific requirements.