Properties And Influencing Factors Of Adhesive Materials Used In External Thermal Insulation System Of External Wall

As the main form of wall insulation,the external thermal insulation system of the external wall has the advantages of simple construction,wide application and remarkable energy saving effect,but there are also many safety risks due to the quality problems such as empty drum and falling off in the initial stage.As an important component of external thermal insulation system,bonded mortar plays an important role in ensuring the safety of external thermal insulation system.This study systematically studied the influence law of the composition,curing mode,testing method,bonding area and other factors on the bonding performance of external wall insulation system.The research results have certain engineering guiding significance for ensuring the quality and safety of external wall insulation system.The specific research work is as follows:(1)Through the influence of different amounts of adhesive powder on various properties of bonded mortar,it is determined that the properties of polymer bonded mortar with a content of 2.5% are relatively excellent.(2)The bonding strength of the binder mortar configured with fly ash and mineral powder(the proportion is 30% fly ash and 10% mineral powder)has been greatly improved,and it has better plasticity and flexibility.(3)The composition of the bonding material was analyzed,and the comparison between Y25 and Y25C30D10 showed that the mechanical properties of the bonding mortar with admixtures were significantly improved;The adhesion and antifreeze properties were obviously improved,and the shrinkage was also reduced.(4)The comparative test on the bonding strength of test blocks of different sizes shows that: the larger the bonding area,the higher the bonding strength;For test blocks with the same bonding area ratio,the bonding strength of bonded mortar and insulation board is related to the density of the insulation board itself,and the bonding strength will increase with the increase of the density of the insulation board.(5)The different curing systems have a significant effect on the bond strength of the bonded mortar,especially the strength of the late 28 d.Under the alternate curing mode(standard curing 2d,water culture 5d,natural curing 21d),the bonding strength of the bonded mortar is the highest.(6)By comparing the test results of different standards,it is found that the test method for bonding strength in GB/T 29906-2013 is more operable than that in JC/T 992-2006 and JCJ144-2004.(7)The possible problems in the construction of external wall thermal insulation were analyzed from the two aspects of external wall thermal insulation raw materials and construction technology,so as to effectively avoid and prevent the risks caused by energy saving defects and achieve the purpose of improving the energy saving effect of external wall thermal insulation.