Research on Modified High-Performance Cement Mortar of Prefabricated Buildings Based on Orthogonal Test

In order to improve the construction technology level of the connection nodes of prefabricated buildings and improve the mechanical properties, fluidity and economy of the connection mortar, this paper adopts the orthogonal experimental design to improve the cement mortar by adding polymer dispersible polymer powder. A modified high-performance mortar with 1d compressive strength of 11Mpa, 3d compressive strength of 19Mpa, 7d compressive strength of 26Mpa, fluidity of 102 mm and final compressive strength higher than M25 was studied. The factors and levels of the orthogonal test are: mortar ratio 1:3,1:4,1:5; silica powder content of 4%,6%,8%; dispersible polymer powder content of 3%,5%,7%. After research, the optimal mixing ratio of modified high-performance mortar is 1:3, the content of silicon powder is 6%, the content of redispersible latex powder is 3%, the content of early strength water reducing agent is 0.1%, and the content of defoamer is 0.5%. The new modified high-performance cement mortar is characterized by short setting time and high early strength, which provides a new idea for the connecting materials of prefabricated buildings, which is of great significance for improving the integrity of prefabricated buildings and the durability of the connection.