1. Synthetic fiber concrete is a new technology

In order to improve the poor tensile properties of concrete, crack resistance and ductility of defects and poor performance of the concrete mixing fibers to improve the performance of concrete, developed quite rapidly. More current research has steel fiber, alkali-resistant glass fibers, carbon fibers, aramid fibers, polypropylene fibers or nylon fibers. The early 60s of last century, foreign countries have the possibility of someone as cement mortar reinforced with synthetic material, the discovery of nylon, polypropylene and polyethylene fibers help to improve the impact resistance of the mortar. Early 1970s, the United States, Britain and other countries have begun to polypropylene monofilament fiber used in concrete products and engineering. Mid-1970s, the United States vigorously develop polypropylene film split tow connected to replace steel mesh to control shrinkage of concrete. The early 1980s, they have developed a series abroad may be incorporated in the concrete monofilament synthetic fibers, made of a material polypropylene, nylon, polyester, polyacrylonitrile, polyethylene, polypropylene monofilament fibers which Because of its low price, high chemical resistance, and the source is relatively large number of broader applications. Over the last decade, the United States, Canada and other countries, the widespread use of synthetic fibers mixed with low rates of ready-mixed concrete. The United States currently total amount of concrete used in about 10% of synthetic fiber concrete. In recent years, China has also begun to gradually synthetic concrete application of this new technology to solve the problems of many new projects increasingly happening.

Laboratory and process a large number of architectural practice has proved that adding a low dosage in concrete reinforced polypropylene fibers, can effectively inhibit the early plastic shrinkage and the generation and development of cracks in concrete segregation of concrete temperature crack effectively improve the concrete bleeding water, conservation of the usefulness of early prevention and reduction of microfilm crack crack dry, the temperature change caused the concrete to harden late. Can effectively improve the performance of concrete cracking, impermeability, frost, shock, wear. A large number of fine fibers uniformly dispersed Bonding cement-based materials, which greatly maintain the overall strength of the concrete, increasing the toughness of concrete, concrete structures contribute to the overall improvement of the concrete when the force of fiber absorbs a lot of energy, so as to effectively reduce concentrated stress the role, hindering the rapid expansion of micro-cracks in concrete, reinforced concrete impact and shock resistance, improved fatigue life of concrete.

2. Promote the use of synthetic fiber concrete strategic significance

Represented imported fiber concrete reinforcing fibers are quickly being accepted industry construction projects in recent years, depending on the country at present for such new technology, new materials are needed and welcome. Durability of concrete structures of very serious problems, not only affect the economic rationality of life, safety, many structures are threatened. Many concrete structures, including bridges, roads, tunnels, ports, dams, buildings, etc., occur during construction or built not long after the visible cracks, affecting the appearance, durability erosion affect the environment to run the structure, but also to make some structural Use function is affected, exposing more serious durability issues. Only seriously address the durability of concrete structures of various types, in order to make resources fully utilized. Possible to extend the life of all types of buildings, delay due to the passage of time has brought the threat of structural safety, to ensure its normal use, in order to save as much as possible to rebuild and repair costs. Data show that in some countries, directly affecting the corrosion of reinforced concrete on the economy, accounting for 3-5% of GDP in national economic output, China is currently engaged in an unprecedented large-scale infrastructure world, but if you can not effectively question the durability of effect, the future will inevitably a large-scale restoration period.

In a large number of concrete structures popularized synthetic fiber concrete, not only can solve the current due to the high buildings and large, some of the problems brought about by the development of structural complexity, so that the quality of construction works near future be guaranteed in the long term durability of concrete structures have The strengthening, can extend the life of the building. Promotion of synthetic fiber concrete technology, is a Quo, the people of the great thing, the whole society is of strategic significance.

China is of such new technologies, new materials are needed and welcome. At present, China is in the period of large-scale infrastructure, residential housing construction is also developing rapidly. Cracks in concrete from the effective control of this point of view, not only the quality of construction projects recently guaranteed in the long term durability of concrete structures has also been strengthened, can extend the life of the building. Promotion of synthetic fiber concrete technology, is a Quo, the people's great news.

3. Prospects for concrete admixtures

Concrete admixtures in concrete widely used, has made it essential for the fifth concrete components, concrete admixtures is characterized by small breed content, plays an important role in improving the performance of the new hardened concrete mixing, Research and application of additives to promote the technology and the development of new varieties of concrete concrete construction. High performance concrete is concrete at home and abroad in the field of research focus, high performance concrete is a good workability, high strength, good volume stability, high durability of concrete, is the product of concrete into the high-tech era in the 21st century important building materials.

The most important characteristic of high performance concrete is excellent durability, durability of up to 100-500, is 3-10 times that of ordinary concrete. To achieve high durability of concrete, we must first reduce the water-cement ratio to produce a dense impermeable concrete. The most important technical approach is to use concrete to achieve the high performance quality and superplasticizer admixture (also known as admixture). The former can reduce the water-cement ratio of concrete, increasing slump slump loss control, given the high density and excellent performance of concrete construction; the latter can fill the gap cementitious materials involved in the hydration of cementitious materials, concrete improvements The interface structure and improve the density of concrete, strength and durability. Development and application of additives can also be said of the 1990s, the era of the concrete into the performance.

High performance concrete to become important in the 21st century materials, concrete admixtures play a major role, it is understood the responsibility of concrete admixture manufacturers is quite significant.