Latest research and development progress and market development trend of China's concrete admixture industry
The China Building Materials Federation Concrete Admixture Branch conducts a nationwide survey on the production of concrete admixtures every two years. The purpose is to grasp the latest developments in the industry and provide an accurate basis for formulating industry development policies. The investigation has been going on for more than ten years.
The latest survey data shows that the total output of concrete admixtures in China reached 13.99 million tons in 2017, a slight increase compared with the 13.803 million tons in 2015; the effect of the optimization of the structure of the admixture industry is very obvious, the new carbon 4 polyether The proportion of products with better performance of polycarboxylate superplasticizer, liquid alkali-free accelerator, new polymer air entraining agent continues to increase; admixture enterprises use stock market capital, scale development, industry concentration Gradually improve. Concrete is composed of cement, sand, stone, admixture and water. It is prepared by mixing and mixing these materials. Concrete is one of the important materials in the construction industry and is widely used in building construction, roads, bridges, dams, etc. Construction work for all types of infrastructure. At present, China is in the process of urbanization construction, a large number of infrastructure needs to be built, so China's concrete utilization ranks among the best in the world. Concrete is the quality assurance of infrastructure, and the factors affecting the quality of concrete include the material of raw materials, age, ambient temperature and humidity, admixtures, etc. Admixtures, as one of the factors affecting the quality of concrete, are gradually being studied with increasing use of concrete. Concrete admixtures are often referred to simply as admixtures. Their main function is to incorporate a certain amount of admixture to improve concrete performance through physical and chemical reactions before or during concrete agitation. Initially, the addition of admixtures to concrete was only to save the amount of cement. However, with the continuous development of science and technology, the types of concrete admixtures are increasing. From the process of classification of admixtures, it can be seen that concrete admixtures mainly improve the performance of concrete by changing the water consumption of concrete to increase the workability of concrete; increasing the concrete by adjusting the setting time of concrete. Hardening performance; increase concrete workability and water washability by reducing concrete bleeding and segregation; compensate for shrinkage by adding expansion agent to reduce concrete shrinkage; others such as adding admixture to increase concrete strength, antifreeze , impermeability, corrosion resistance and so on. At present, with the rapid development of science and technology, China's concrete admixture industry is at a high-speed development stage, various admixtures have been improved and new varieties have been developed. High-efficiency water reducer is widely used because of its high water-reducing rate. After decades of development in China, it is now possible to independently produce multi-variety and multi-functional high-efficiency water reducer, but the research of various types of water reducer The level of application also varies in different regions with economic distribution and market demand. Since 2000, the concrete research community in China has gradually recognized the high efficiency of polycarboxylate superplasticizers. The superplasticizer is a petrochemical product which is formed by copolymerization of an unsaturated monomer under the action of an initiator, so that the side chain of the reactive group is branched onto the main chain of the polymer without affecting the coagulation hardening of the cement. In this case, it has the functions of high-efficiency water reduction, control of slump loss and anti-shrinkage, and has strong adaptability to cement. However, China started late in this respect. There are still many shortcomings in the country where scientific research results accumulation, production techniques and application experience in actual projects are relatively early. For example, at present, China has not been able to develop multi-variety polycarboxylate-based superplasticizers, lacking advanced modification means for polycarboxylates, and has not solved the problem of incorporating polycarboxylate-based water reducers. A method of delamination and severe bleeding in concrete. In recent years, construction engineering has become more and more demanding on concrete. It requires not only high strength and durability, but also high workability. Concrete admixtures are constantly being used as a way to improve concrete performance. Research and development, so the variety of concrete admixtures is also increasing. China's only GB50119-2003 concrete admixture application technical specifications, the standard supervision and guidance of the admixture industry is somewhat thin. Therefore, we must constantly improve the existing admixture specification system, introduce new guidelines for the production process of admixtures, the quality inspection system for admixtures and related penalties, standardize the naming methods and labels of concrete admixtures, and standardize the market for concrete admixtures.