Study on Application of Early Strength Agent in Polymer Protective Mortar

Abstract

With the development of the world economy, the subway has become more and more widely used in various environments. As one of the important materials of the subway project, concrete urgently needs to solve the problems of the subway concrete structure protective layer falling off and steel corrosion caused by harsh environment erosion, so the development of high-performance protective mortar has been a hot research topic. In this paper, calcium formate and anhydrous sodium sulfate as early strength agents, polymer and anti-cracking fiber were added toordinary Portland cement mortar. The bending and compressive strength of ordinary Portland cement mortar at 1d, 3d, 7d and 28d, and the bond strength at 14d and the practical application value were analyzed comprehensively. The results show that the optimal content of calcium formate is 1.5% and anhydrous sodium sulfate is 1% respectively. When the optimal dosage is not reached, the early strength of cement mortar will be increased with the increase of the early strength agent, but when the dosage exceeds the optimal dosage, the early strength of cement mortar will not increase, but will be flat or even decrease significantly.