The function of water reducing agent is to improve the working performance of freshly mixed mortar and improve the fluidity of mortar without reducing the amount of cement; while maintaining certain working performance, reduce the water consumption of cement and save cement; improve the mortar mixture Pumpability and other physical and mechanical properties of mortar. When high-efficiency water-reducing agent is added to the mortar, the water-cement ratio can be significantly reduced, and the better fluidity of the mortar can be maintained. Generally speaking, the water-reducing rate of high-efficiency water-reducing agent can reach about 20%, while that of ordinary water-reducing agent is about 10%. At present, it is generally believed that the water-reducing agent can produce water-reducing effect mainly due to the adsorption and dispersion of the water-reducing agent.
Research on the hardening process of cement in mortar, it can be found that during the mixing process of cement with water, because the cement mineral contains components with different charges, the mutual attraction of positive and negative charges will lead to concrete flocculation structure. The flocculation structure may also be formed due to the thermal movement of the cement particles in the solution causing them to collide and attract each other at certain edges and corners.
Because a lot of mixing water is wrapped in the flocculation structure, it can not provide more water for cement hydration, so the ease of fresh concrete is reduced. Therefore, in order to make the cement better hydrated during construction, it is necessary to increase the water consumption accordingly during mixing, but the increase in water consumption will lead to the formation of too many pores in the cement stone structure, resulting in a decline in physical and mechanical properties .