At present, the external wall insulation materials used in China generally include traditional inorganic materials (rock wool, glass wool) and organic synthetic materials (organic foam materials such as PS and PU). Insulation material production and processing energy consumption is huge, long-term use of heat preservation effect: fruit instability, complex construction process, especially the material use process and post-treatment have an impact on the environment and the human body, in some occasions even in some countries are banned . Organic insulation materials have excellent insulation effects. For example, traditional polystyrene board and polyurethane foam occupy a large share of the wall insulation material market in China. However, since it has been widely used in civil buildings, fire accidents have continued, resulting in huge Economic loss and personal injury. Therefore, the research and development of building wall insulation materials and the design of wall insulation systems should place safety and energy conservation, fire protection and heat preservation at an important position. : With the rapid development of modern building insulation technology and modern building insulation materials. Exhibition, requires us to study, analyze and summarize the performance of building insulation materials, broaden the application and innovation of new materials and new technologies, find some good insulation effect, excellent combustion performance, perfect insulation system, convenient construction, green environmental protection and economy. Feasible material. 1.1 Polystyrene Foam Board (EPS) Fund Project Funded by the Central University's Basic Research Business Fund (DC110112) Polystyrene foam is an organic material that is molded into sheets of different thickness for use as exterior insulation for buildings. , also known as molded polystyrene foam board (referred to as polystyrene board, EPS). The thermal conductivity of EPS polystyrene board is generally 矣0.042W/m K, so it has excellent thermal insulation performance, and also has good waterproof performance and wind pressure resistance and impact resistance. The insulation system has mature technology, convenient construction, low cost and high cost performance. For many years, it has dominated the materials used in the construction of exterior wall insulation in China. The EPS polystyrene board has a burning performance of B2 grade, and has poor fire resistance, and the heat distortion temperature is only 70 to 98. Polystyrene is composed entirely of hydrocarbons, which is extremely easy to burn in nature. The amount of heat released by combustion is large, and the amount of smoke is also large. It shrinks and melts after being fired, resulting in cavities in the external thermal insulation system. The drip is ignitable. Therefore, it is not recommended to use, it should be withdrawn from the building exterior wall insulation market. 1.2 Extruded polystyrene foam board (XPS) extruded polystyrene foam board (referred to as extruded board, XPS) is an organic type of insulating material, which is continuously extruded by a special process. The internal foam is completely closed and continuous and uniform, and has a honeycomb structure with a thermal conductivity of 30.03W/m K. Compared with the EPS polystyrene board, it has higher strength, better thermal insulation performance, and more gas impermeability. Features. The XPS system has improved the grade of the EPS system, which is a more commonly used insulation system after the EPS system. The fire resistance of XPS extruded board is the same as that of EPS polystyrene board. It is also an organic material. It has the characteristics of poor fireproof performance. It is a flammable material with a burning performance of B2. Reach level B1. In February 2009, the fire of the CCTV new site was a man-made disaster, but indirectly ignited the building's outer wall insulation material extruded board, which became an accomplice to the fire. It is therefore not recommended to continue using this material. 1.3 Polyurethane outer wall insulation (PU) polyurethane exterior wall insulation (PU) is an organic insulation material, and its exterior wall insulation system includes two processes: on-site foaming construction and factory prefabricated board. The thermal conductivity of polyurethane exterior wall insulation materials can reach 0.017 ~ 0.025W / mK, which is the smallest thermal conductivity material in traditional organic and inorganic insulation materials. The PU rigid foam adheres firmly to the surface of the base wall, has high wind pressure resistance, impact resistance and strain resistance, and also has excellent waterproof and steam barrier properties. Polyurethane is an organic material with a combustion performance of B2 grade. It is a combustible material. Polyurethane with flame retardant can also reach B1 grade, and it is conventionally treated according to B2 grade. Its forced ignition temperature is 310T: and the auto-ignition temperature is 415T:. When it is heated, it usually decomposes flammable gas. When burning, it is mostly incomplete combustion. The smoke contains a large amount of toxic gases such as carbon monoxide, carbon dioxide, hydrogen cyanide and formaldehyde, and generates a large amount of soot, which is easy to cause. Casualties. It is the polyurethane insulation material used in energy-saving renovation that caused the fire to spread rapidly in the fire in the Jiaozhou Road teacher apartment in Shanghai. The lack of polyurethane in fire resistance has affected the continued use of this material. 1.4 Mine (rock) cotton ore (rock) cotton including slag cotton, rock wool, glass wool and ceramic fiber, etc., is an inorganic insulation material, thermal conductivity less than 0.044W / mK, light weight, durable, non-combustible, non-corrosive, It is not subject to insects and other characteristics, and is an excellent thermal insulation and sound absorbing material. Previously used as insulation material for industrial thermal equipment and refrigeration plants. Mineral (rock) cotton is a non-combustible material. Some organic binders will be added during the production process. Although the combustion performance is slightly affected, it is generally considered that the combustion performance of the mineral (rock) cotton is Grade A. In particular, the fires that have occurred in recent years using organic insulation materials have led to the increasing use of mineral (rock) cotton in the building insulation industry. However, since the mineral (rock) cotton capacity is more important than the organic thermal insulation material and the internal strength is slightly poor, it must be protected and fixed during construction to avoid deformation caused by excessive self-weight. Moreover, when the wall surface is not well sealed, water absorption will occur. The insulation layer becomes a water storage layer, which greatly increases the thermal conductivity, reduces the heat preservation effect, and increases the weight of the insulation layer to cause the waterproof layer to break and cause leakage. . These weaknesses have affected the use of mineral (rock) cotton as an insulation material for exterior walls. 2 kinds of new materials for exterior wall insulation and their fire resistance 2.1 Phenolic resin foaming material (PF) Phenolic resin foaming material is a polymer organic material, with modified phenolic resin as the main material, and closed pores produced by adding additives. Rigid foam, which is light, fireproof, non-flammable, non-flammable, non-toxic, non-dripping, non-shrinking at low temperature, no embrittlement, no environmental pollution, good processability, and convenient construction. It is made of mold, can be machined, and can be foamed in the same way as polyurethane construction. Due to the high closed cell ratio, the phenolic resin foamed material has a low thermal conductivity of only about 0.023 W/mK, good heat insulation performance, and water resistance and vapor barrier properties. The phenolic resin foaming material has a burning property of B1 grade and is a flame retardant material. After modification, its flame retardant grade can reach Grade A. Although the phenolic resin foaming material belongs to the organic heat insulating material, the phenolic heat insulating board has good heat insulating effect and excellent fireproof performance, and its comprehensive performance is an ideal fireproofing and energy-saving material among various heat insulating materials. It is also recognized internationally as a new building insulation material with a promising future, so it will become a very competitive new building material. Foam glass foam glass is an inorganic non-metallic glass material made of cullet, foaming agent, modified additive and foaming accelerator, which is finely pulverized and uniformly mixed, then melted at a high temperature, foamed and annealed. It has low bulk density, low thermal conductivity (0.058W/mK,), no moisture permeability, no water absorption, no combustion, no mildew, high mechanical strength and easy processing. It is a lightweight, high-strength building material and decorative material with excellent performance, heat insulation, sound absorption, moisture resistance and fireproofing. It has a temperature range of 196T: zero to 450T: zero, and Class A does not burn with the same life. It is not only safe and reliable, but also durable in the harsh environment of low temperature, deep cooling, underground, open air, flammable, damp and chemical attack. It is known as “permanent insulation material without replacementâ€. Therefore, it is widely used in the insulation and cold preservation of permanent projects such as petroleum, chemical, construction, cold storage, underground engineering, shipbuilding, and national defense. As a new type of material used in construction, foam glass is an excellent thermal insulation material for roofing or exterior walls. At present, foam glass is rarely used in China, mainly because of its low productivity and relatively high production cost. Compared with other exterior wall insulation materials, it lacks competitive advantage. If a large area is used on the outer wall of a building, it is necessary to tap the potential in technology and production technology, increase productivity, and thus reduce costs. It can truly give full play to the superior material properties and functions of this new material, and make a response to building energy conservation. Some contributions. STP vacuum insulation board STP vacuum insulation board is a kind of vacuum insulation material. It is a composite of filled core material and vacuum protection surface layer. It can effectively avoid heat transfer caused by air convection, so it has extremely low thermal conductivity. 0.008W/m K. It is ultra-thin, light, fire-proof, environmentally friendly and energy-efficient. It has a service life of 60 years and is basically the same as the building. It is the most advanced and efficient insulation material in the world. STP vacuum insulation board is inorganic insulation material, fireproof and non-combustible, and its combustion performance reaches Grade A, meeting the fire protection requirements of the Ministry of Public Security Fire Department for civil building exterior insulation materials. As a new, efficient and non-combustible building insulation material, STP vacuum insulation panels have broad application prospects. 3 Conclusion At present, in China's traditional building exterior wall insulation materials, organic insulation materials have good insulation performance, but have the risk of causing fire. Inorganic insulation materials, although they are all non-combustible materials, do not have fire safety problems themselves, but other properties cannot fully meet the requirements of external insulation. Organic and inorganic composite insulation materials, although the fire performance is acceptable, but to achieve the insulation effect, the thickness of the wall will be increased invisibly. Therefore, it can be seen that the better the insulation performance, the worse the fire performance is often. On September 25, 2009, the Ministry of Public Security and the Ministry of Housing and Urban-Rural Development jointly formulated carbon sulphite-type sulfate erosion for civil water-based materials. Zhao Zhongqiang Li Changcheng 2, Tang Hui 3, Li Yilong 3, Tian Zhichao 3 (1. Shangdi Xingda Group Co., Ltd., Beijing 102218, China; 2. State Key Laboratory of Green Building Materials, China Academy of Building Materials Science, Beijing 100024, China; 3. Tianjin North China Geological Exploration Bureau, Tianjin 300170, China) Characterization, formation mechanism, chemical model, degradation model, carbon Precautionary measures for sulphite-type sulphate attack, and pointed out that there are problems in the current research. At present, limestone powder is gradually being widely used in the cement concrete industry. However, studies have shown that 1-3, when there is sufficient sulphate, water and temperature is appropriate (commonly considered <15T, cement-based materials with limestone powder may be damaged by the sulphite-type sulphate attack (TSA). Traditional Different from sulfate attack, the formation of carbon sulphite directly destroys the main gelling component CS-H gel in the cement stone, and transforms it into a sludge-like substance, which falls off from the surface and ends, eventually leading to the complete loss of the cement-based material. Gelation. Since 1965, there have been reports of engineering degradation 3-5 caused by hundreds of TSA damages at home and abroad. China's Lanzhou Bapanxia Hydropower Station and Yonganba Reservoir in Kashgar, Xinjiang have also experienced different degrees of TSA damage. -7. Obviously, TSA damage is a ubiquitous and long-term unconstrained form of damage to concrete durability. If effective preventive measures are not taken in actual engineering, it may affect the durability of concrete. 1 Research progress of cement-based materials TSA In recent years, TSA has become one of the hotspots of cement-based materials research. Domestic and foreign scholars have done a lot of research on the composition, identification, formation mechanism, failure mechanism and preventive measures of carbon sulphite. jobs. 1.1 Composition and test method of carbon sulphite The chemical formula of the sulphite is CaCO3 CaSiO3CaSO415H2, and the Si and OH- in the molecule are hexa-coordinated with 2-, and the octahedral group is used to identify the formation of sulphurite. And the important theoretical basis of TSA. Since the crystal structure and morphology of the sulphite are very similar to those of ettringite, it is difficult to distinguish between sulphite and ettringite by conventional testing methods, which makes it impossible to accurately determine the damage of cement-based materials because of ettringite and gypsum. The swelling damage is caused by the destruction of TSA caused by the formation of the carbon sulphite. Studies have shown that full-spectrum line fitting and Ri-etveld methods 8-9 using X-ray powder diffraction data analysis can accurately quantify the amount of carbonite, ettringite and ettringite in a mixture without standards. Scanning electron microscopy combined with EDS spectroscopy can be used for qualitative identification. Infrared spectroscopy, Raman spectroscopy and Raman chemical imaging, 29Si NMR spectroscopy and thermal analysis have also been confirmed to distinguish between sulphurite and ettringite. However, most test methods can only achieve qualitative or semi-quantitative analysis, and it is impossible to accurately determine the proportion and amount of carbonite in the corrosion products. 1.2 Carbon sulphite formation mechanism At present, there is no consensus on the formation mechanism of carbon sulphite, but studies have shown that there are two main formation mechanisms of carbon sulphite: 1 direct reaction mechanism; 2 ettringite Transformation mechanism. (1) Direct reaction mechanism, the sulfate and carbonate present in the liquid phase of the cement slurry react directly with the CSH gel to form the carbon sulphite. The reaction formula is as follows: the external thermal insulation system and the external wall decoration fire protection provision, Building fire protection of different heights and different uses has been specified in more detail. However, this provision has not been effectively implemented. On March 14, 2011, the Fire Department of the Ministry of Public Security issued a Circular No. 65 on further clarifying the relevant requirements for fire protection supervision and management of civil building exterior insulation materials, requiring that the civil building exterior insulation materials be burned before the new standards are issued. The performance is a Class A material". Among the new materials for exterior wall insulation, the phenolic insulation board should be an ideal environmentally friendly green insulation material for fire protection and energy conservation. Foam glass has excellent thermal insulation and fireproof performance, and its life is synchronized with the building. It is a lightweight and high-strength building insulation material. The excellent insulation effect of the vacuum insulation board and the ultra-thin insulation thickness make it a good prospect for use in the building. These new materials for exterior wall insulation are both excellent in insulation and fire resistance, and will surely be widely used in future building exterior walls. However, in terms of cost, it is still necessary to reduce the market share. (Finish) Alloy steel refers to steel with high strength and good chemical stability at high temperature. It includes two types of anti oxidation steel (or high temperature resistant steel) and hot steel. Anti oxidation steel generally requires good chemical stability, but the capability is limited. High temperature strength and the corresponding oxidation resistance of heat and strong steel are required. Heat-Resistance Steel is often used in the manufacture of boiler, steam turbine, power machinery, industrial furnace and aviation, petrochemical and other industrial sectors in the work of the high temperature parts. 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