Optimization of Mix Ratio of Epoxy Mortar with Super-Early Strength Based on Orthogonal Test

Abstract

Through adding accelerator to common epoxy mortar and optimizing its mix ratio by orthogonal test, the influences of the contents of filler, diluent, curing agent and accelerator on the early strength of epoxy mortar were studied respectively. Results showed that the filler content has the most significant influence on the compressive strength and splitting strength of epoxy mortar, and the optimum combination of these four contents is A2B2C3D2, on which condition compressive strength of epoxy mortar can reach 71.4 MPa and splitting strength 6.72 MPa at super-early stage (4h, at nursing temperature 25 C). Pull-out test on the anchor bolts with optimum-mix-ratio epoxy mortar as anchorage agent was carried out, and compared to tests with quick setting cement as anchorage agent, proving that the pull-out strength with epoxy mortar as anchorage agent was much higher than that of quick-setting cement. The ultimate pull-out strength of the anchor increased with anchorage depth at pull-out bonding failure, which indicates that the optimized epoxy mortar with super-early strength can meet the needs of emergency repair and other special projects, and can be applied in the fields of structural reinforcement and rapid repair of traffic engineering.