Rheological Properties of Epoxy-Grouting Materials for Early Cracks of Cast-In-Situ Concrete on Bridge Deck

The rheological property of epoxy grout is related to whether the grouting material can completely fill the early cracks of the cast-in-situ concrete on the bridge deck. To reveal the rheological properties of epoxy grouting materials, epoxy grouting materials epoxy grouting material mixed with active diluent BGE (EP-I) and epoxy grouting material mixed with active diluent 1,4-BDE (EP-II) were prepared. The viscosity change of epoxy slurry with time under different diluent content was revealed. And the operational viscosity index was put forward to comprehensively evaluate the working characteristics of epoxy slurry with different diluents. Then, the gel time and groutability of two kinds of epoxy grout were compared and analyzed. Finally, the isothermal viscosity time-varying model of EP-I epoxy slurry was established. The results show that the viscosity of epoxy slurry decreases with the increase of diluent content, and the viscosity of epoxy slurry changes with time in the form of an exponential function. And the operational viscosity of EP-I epoxy slurry is significantly lower than that of EP-II, but its gel time was longer than that of EP-II. Both types of epoxy grout with 15% diluent can effectively fill the concrete early cracks (width 0.8 mm) within 10 min. Based on diffusion theory, single epoxy diluent butyl glycidyl ether (BGE) was more conducive to the penetration and diffusion of epoxy slurry. The isothermal viscosity time model of epoxy slurry can better reflect the relationship between viscosity and temperature, time. The goodness of fit between the model curve and the measured value is higher than 0.90, which has good reliability.