Study On The Effects Evaluation And Optimization Method Of Connectors On The Thermal Performance Of External Wall Insulation System

In the building’s energy consumption,the proportion of energy lost through the building envelope is more than 50%,and the proportion of the building’s exterior wall in the envelope is larger.The use of an external wall insulation system is an important method to improve the thermal performance of the building envelope.With the passage of time,the traditional external wall insulation technology has exposed obvious drawbacks: First,the life of the external wall insulation is much lower than the design life of the main body of the building;second,the traditional external wall insulation technology’s product quality and construction quality are often difficult to ensure,making it very easy to cause a variety of quality and safety hazards,some serious and even producing fire and other safety accidents,causing major losses to people’s lives and property security.The reinforced composite rock wool board insulation system using building wall insulation and structural integration technology can not only effectively solve the insulation system and the main body of the building with the life of the problem,but also in the seismic,safety,and other performance has been strengthened,can simultaneously meet the building,fire,and other requirements.But the existence of metal connectors(steel anchor bolts and wire mesh)in the insulation system reduces its thermal performance.In this paper,we study the influence of the connectors in the reinforced composite rock wool board insulation system on its thermal performance and its influence law and put forward an optimization scheme combined with the mechanical properties of the insulation system.First of all,a method for quantitatively evaluating the impact of connectors on the insulation system’s thermal performance was suggested.The protective hot box method was used to examine the impact of connectors on the reinforced composite rock wool board insulation system.The effectiveness of employing the protective hot box approach to investigate how connectors effect the reinforced composite rock wool board insulation system’s thermal performance was tested using theoretical calculations.The findings indicate that the usage of connectors has a detrimental effect on the insulating system,with steel anchor bolts having a greater influence than wire mesh.Secondly,the effects of connectors on the thermal performance of the reinforced composite rock wool board insulation system and its effects law was studied by using the finite element numerical simulation method,and the feasibility of this finite element numerical simulation method was verified by using the protective thermal chamber method.The results show that the effects of the connectors on the insulation system varies regularly with the thickness of the insulation material,the size of the connectors,and the number of connectors.Then based on the law of the effects of the connectors on the thermal performance of the insulation system.The optimization scheme to reduce this unfavorable shadow is proposed in combination with the mechanical properties of the insulation system(gravity load and wind load).The results show that when the thickness of the rock wool board in the insulation system is 70 mm,100mm and 140 mm,the influence of the connectors on the heat transfer coefficient of the insulation system is reduced by 6.9%,5.3% and 4.4% respectively after using the optimized scheme.Finally,the effects of the connectors on the thermal performance of the insulation system in the actual project was studied by using the field measurement method,and the effects of the connectors on the thermal performance of the insulation system was verified.This study helps to guide the calculation of thermal performance of the envelope structure,and is of great significance to reduce the building energy consumption and promote the application of this new type of external insulation system in energy-saving buildings.