Research on the preparation of rapid repair materials for bridge expansion joints

In order to solve the problem of the long repair time of bridge expansion joints that may result in long road closure periods and reduced vehicle traffic efficiency, a rapid-curing cement-based mortar material was prepared in this paper on the basis of special cement material through the adjustment of formulation and mineral admixture. The optimum mortar mix proportion obtained through research is as follows: cement-sand ratio is 1:1.1, water reducer is 0.2%, and the ratio of silica fume, mineral powder, and fly ash to cement is 6%, 2%, and 2% respectively. The 2h flexural strength and 2h compressive strength of the material obtained with the optimum formula reached 7 MPa and 24 Mpa respectively. Moreover, it has good fluidity and setting time properties without an obvious decrease in long-term strength, so it is an ideal rapid repair material for bridge expansion joints.