The Study Of Shear Bond Strength Of Thermal Insulation Layer In Exterior Insulation System

The building energy efficiency plays a key role in the national energy efficiency work, and the promotion of Exterior Insulation and Finish Systems(hereinafter referred to as EIFS) is vital to realize the building energy efficiency. Due to the late development of EIFS at home, it still remains the application stage without any complete practical and theoretical basis. As long as 40% of adhesive area is satisfied, the adhesive layout depends on workers’ experience. Moreover, an eyeful of insulating materials and adhesives in the market may pose a threat to the quality control and promotion of EIFS. Plus the bulking and peeling of the insulating layer, especially the large peeling area of the insulating layer would cause the EIFS to lose the insulating capacity partly or completely and thus affect the normal use of insulating system in a serious way. Therefore, we need to delve into the adhesion of the insulating layer and the structural layer, confirm the adhesive mode and ensure no-peeling of the insulating layer, which is significant to promote the EIFS and to carry out the building energy efficiency work.Firstly a field investigation for the exterior insulation and finish systems was conducted in Jingzhou, the causes of bulking, crack, peeling of the EIFS in practice was analyzed, and the improvement measures in terms of design, construction and materials was put forward.Secondly, by reference to the study of national and international scholars on the bond property of insulated layer, and according to relevant practices of EIFS, an experimental study was conducted on the shear bond strength of three insulating materials—XPS, EPS and PUR in terms of different adhesive area, different defect parts and different defect shapes.The study shows that the property of insulating material determines the failure mode; the defective parts can affect the shear bond strength directly; different defect shapes can lead to the discrepancy of shear bond strength due to the different boundary constraints. Therefore, appropriate adhesive modes should be adopted according to different insulating materials to ensure the bond strength of the insulating layer.