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Foamed concrete may become a thermal insulation material for southern buildings

Thermal insulation materials are an important factor affecting building energy conservation. At home and abroad, there is a general emphasis on the thermal insulation performance of buildings in order to greatly reduce energy consumption, thereby reducing environmental pollution and the greenhouse effect, and at the same time improving the comfort of the living environment. The energy loss of Chinese houses is roughly 50% for walls; 10% for roofs; 25% for doors and windows; and 15% for basements and floors. In order to achieve real energy conservation in buildings, all the roofs, walls, walls, and ground must be kept warm and insulated. As the initiator of the Foam Concrete Branch of China Foam Concrete and Cement Products Association, when talking about the development direction of building insulation materials in southern China, Mr. Lu Wencheng, chairman of Beijing Zhongke Zhucheng Building Materials Technology Co., Ltd. pointed out that foam concrete can be Building roofs, walls, walls, and the ground can be heat-insulated materials, and its technical characteristics are more suitable for the climatic conditions of southern China with a small temperature difference between indoor and outdoor; foam concrete can be said to be the thermal insulation of buildings in the southern region under current conditions Material. As a rising star of lightweight concrete, foam concrete is developed on the basis of aerated concrete. Since aerated concrete needs autoclave and cannot be constructed on site, although it has been used for many years, its promotion is still subject to certain restrictions, so people invented foamed concrete. Its performance and pore structure are close to that of aerated concrete, but it does not require autoclave, which is very suitable for the current environmental protection and low-carbon waste management policy and environment requirements, and can greatly reduce energy consumption. The water absorption and thermal conductivity of foamed concrete are far lower than that of aerated concrete, and it can be easily poured on any building site. In Northern Europe, North America, Sweden, Canada, Finland and other countries, the application of foamed concrete in building insulation accounts for a large proportion and is known as "building insulation clothing." Except for foamed concrete, there is no other thermal insulation material that can be widely used in various parts of the building envelope from head to toe. Foamed concrete is only able to do this because it can not only be poured on-site, but also can form various products. From the material density, it can reach an ultra-low density of 100~300kg/m3, which is close to expanded perlite. It can reach a high density of 600~1000kg/m3, and the strength can be from 0.4MP~10MPa, the thermal conductivity is 0.045~0.14 0.12W/(m·K), and the heat storage coefficient is about 3.0 W/(㎡·K) . (The smaller the thermal conductivity, the better the thermal insulation performance, and the larger the thermal storage coefficient, the better the thermal insulation performance.) In southern my country, the regional climate characteristics with small indoor and outdoor temperature differences determine residences with high thermal insulation performance and weak thermal insulation performance requirements. Therefore, good heat storage coefficient is more important than good thermal conductivity for southern residential construction. The heat storage coefficient of foamed concrete with a bulk density of 700 Kg/m3 is 3.59W/(㎡·K), and the heat storage coefficient of foamed concrete with a bulk density of 500 Kg/m3 is 2.69W/(㎡·K), which is much higher than that of organic The value of foam plastic 0.36 W/(㎡·K). Therefore, whether it is a comprehensive inspection of thermal insulation performance, thermal storage performance, freeze-thaw, strength, light weight, fire and shock resistance, environmental protection and low carbon, construction convenience, construction cost, etc., foam concrete is a building insulation material in southern my country. . At the beginning of this century, Beijing Zhongke Zhucheng focused on the development and application of building thermal insulation foamed cement insulation materials. In 2008, it was listed as the (national) building materials industry technology supervision and research center cement-based foam material research and development center. The patented product ZC inorganic foam insulation board developed by the company is a porous and lightweight inorganic board. It is made of inorganic materials such as cement, fly ash and other solid wastes. After the slurry is injected into the mold, the honeycomb foam concrete insulation board (also called foamed cement insulation board) is formed by cutting and curing after being oxidized, foamed and hardened under natural conditions.