现浇脲醛树脂外墙外保温系统实验与仿真

Experiment and Simulation Analysis of Cast-in-place Urea Formaldehyde Exterior Wall External Insulation System

为了设计以脲醛树脂泡沫保温材料为保温层的外墙外保温系统,首先对各部件材料进行材性试验,给出相应的材料参数;其次采用硅钙装饰板为外模板,设计两种外墙外保温系统方案,并应用有限元软件ABAQUS建模,针对两种方案在温度变形、失水收缩以及风荷载下的受力性能进行模拟分析,给出两种方案的构造措施;最后采用ABAQUS中的brittle cracking本构模型模拟脲醛树脂的本构关系,探究保温层因裂缝扩展而形成热桥的可能性。研究表明:针对哈尔滨等严寒地区的高层建筑,所提出的外墙外保温系统方案满足安全性和经济性要求,同时对建筑高度为30米以下的外墙外保温系统,建议选用Ф24 mm的圆柱形ABS塑料连接件和厚度6 mm的硅钙装饰板,可同时保证结构安全且不产生热桥。

In order to design exterior wall external insulation system as urea formaldehyde is taken as the insulating layer,some material experiments are carried out to determine the material parameters of all parts in the system.Two schemes of exterior wall external insulation system are designed,which use calcium silicate boards as exterior formwork.The finite element software ABAQUS is utilized to simulate two systems under temperature deformation,shrinkage of insulating layer and wind load by model building.Constructional measures of both schemes are put forward.Finally,urea formaldehyde foam insulation uses the brittle cracking constitutive model in ABAQUS as its constitutive relation to investigate the possibility of insulating layer forming into heat bridge because of crack propagation.The numerical results show that the schemes of exterior wall exterior insulation system for civil high buildings in severe cold area like Harbin can meet the demand for safety and economy.It is recommended thatФ24mm cylindrical ABS connectors and6mm thick calcium silicate boards should be chosen in exterior wall external insulation system when the building height is below30m.These can meet not only the demand for safety,but also the rules of not forming heat bridge in the insulation layer.