Effect Of Temperature Stress On The Durability Of EPS Exterior Insulation System

The durability of external thermal insulation system is the key indicator of the building external thermal insulating safety measurement.Poor durability of external thermal insulation system may produce not only the great reduction of heat preservating and energy saving effects,but also the serious potential safety hazard.The external thermal insulation system contacts with the outside natural environment in whole life cycle that its being affected by a variety of loads is very complex.Amoung the lots of influence factors,the temperature stress,having an effect on external thermal insulation system,acts in a very slow,long-time process.Resulting from the obvious performance difference of the materials in the special multi-layer structure,the temperature stress has become an significant factor affecting the durability of external thermal insulation system,accordingly.EPS exterior insulation system,widely using in China region as a form of architectural energy preservation and heat insulation,has been prove its stable in performance by the long period applicational experience at home and abroad.Therefore,this system was used as a typical form of the insulation system for relevant temperature stress researching in this topic.In this research,the essential cause of the influence on durability by thermal stress was analyzed while the rule of it was summarized in a combination of large –scale wall thermal stress testing and finite-element modeling,including thermal stress model creation and component materials performance experiment.Through the experiment it was found that,the temperature stress in every structural layer of EPS exterior insulation system amplified layer by layer along the thickness direction from indoor to outdoor,while the maximize focus on the external surface of the protective layer;The emperature stress has a trend of accumulating and amplifying as the environment temperature continuously waving in a wide range;The stress concentrated much more in some special areas such as the center of the wall and the angle of the window;The destruction to EPS external thermal insulation system made by temperature stress under extreme high temperature in summer is more significant than that under extreme cold environment in winter.It was hoped that we can provide a theoretical basis for security evaluating,designing and construction improving of the external thermal insulation system through above findings.