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Daily life causes long-term aging of building exterior wall insulation materials: thermal stress, wind pressure, seismic force, water or steam, and fire. The specific analysis is as follows:

1. Thermal stress. Thermal expansion and contraction caused by temperature difference will cause volume changes in non-structural structures, making them always unstable. Thermal stress is one of the main destructive forces for external insulation of high-rise buildings. Compared with multi-story or single-story buildings, high-rise buildings have high sunlight intensity, high thermal stress, and large deformation. Therefore, in the design of thermal insulation and crack resistance structures, the selection of thermal insulation materials should comply with the principle of flexible gradient, and the deformation capacity of the outer layer material should be higher than that of the inner layer material.

2. Wind pressure. Generally speaking, positive wind pressure produces thrust and negative wind pressure produces suction, which causes great damage to the external insulation of high-rise buildings. This requires the outer insulation layer to have considerable wind pressure resistance. In terms of wind pressure resistance, the insulation layer is required to have no cavity and eliminate the air layer to avoid wind pressure, especially the negative wind pressure state. The volume expansion of the air layer in the lower insulation layer causes damage to the insulation layer.

3. The force of ground vibration. The vibration force may cause extrusion, shearing or deformation of the structure and insulation surface of high-rise buildings. The greater the rigidity of the insulation surface, the greater the seismic force it receives and the more serious the damage. This requires that the external wall insulation materials of high-rise buildings, under the premise of considerable cohesion, meet the principle of flexible gradient, disperse and absorb ground vibration force, minimize the load on the surface of the insulation layer, and prevent the force of vibration. Large-scale cracking, peeling, or even falling off from the lower insulation layer.

4. Water or steam. In order to avoid damage to high-rise buildings caused by water or steam, external insulation materials with good hydrophobicity and good moisture permeability should be selected to avoid water condensation or increase the moisture content of the insulation layer during the migration of water or steam, and attention should be paid to the insulation materials. Insulation performance. o Improve the resistance to rainwater erosion and freeze-thaw resistance of external insulation of high-rise buildings.

5. Fire and heat resistance. Compared with multi-story buildings, high-rise buildings have higher fire resistance requirements. The insulation layer of high-rise buildings should have good fire resistance and should have the ability to prevent the spread of fire. The strength and volume of the material should not be reduced too much, and the surface should not be cracked or collapsed. This may cause harm to families or firefighters, and bring great difficulties to rescue work.