Pre-mixed mortar generally incorporates a certain amount of water retention and thickening data, and water retention and thickening data generally have strong water demand, thus increasing the unit water consumption of mortar, but also affecting the mechanical properties and durability of mortar, so it is necessary to use appropriate water reducer to disperse the cement slurry system.
There are many kinds of water reducers. In theory, lignin, naphthalene sulfonate, melamine, aminosulfonate, aliphatic and polycarboxylate water reducers can be used as dispersants in cement slurry systems. However, these water reducers not only have their own dispersive, plasticizing and reinforcing effects, but also have great differences with water used. Mud, fly ash and slag powder have certain adaptability.
More importantly, ready-mixed mortar is a mixture of multi-component and different components, especially the existence of thickener, water retaining agent and stabilizer, which greatly affects the plasticization and dispersion of water reducing agent.
Pre-mixed mortar is usually mixed with a certain amount of water-retaining and thickening materials, and water-retaining and thickening materials have strong water demand, thus increasing the unit water consumption of mortar, but also affecting the mechanical properties and durability of mortar, so it is necessary to use appropriate water-reducing agent to disperse the cement paste system. There are many kinds of water reducers. In theory, lignin, naphthalene sulfonate, melamine, aminosulfonate, aliphatic and polycarboxylate water reducers can be used as dispersants in cement slurry system. However, these water reducers not only have different dispersion, plasticization and reinforcing effects, but also have different effects with water. Sludge, fly ash and slag powder have certain adaptability. More importantly, ready-mixed mortar is a mixture of many components and different proportions of each component, especially the existence of thickener and water retaining agent, which greatly affects the plasticizing and dispersing effect of water reducing agent. When a certain component of thickener or water retaining agent exists in aqueous solution, some kinds of water reducing agent can not play its due plasticizing effect, and sometimes even make the fluidity of mortar worse.
Therefore, in the production of high fluidity mortar and the selection of water reducer, a large number of tests must be carried out to verify the selection of the most suitable water reducer varieties and determine its optimal dosage.
When a certain component of thickener or water retaining agent exists in aqueous solution, some kinds of water reducing agent can not only play its due plasticizing role, sometimes even make the fluidity of mortar worse. Therefore, in the production of high fluidity mortar and the selection of water reducer, it is necessary to select the appropriate type of water reducer through a lot of experimental verification, and determine the appropriate amount of water reducer.
