Study On Fire Performance Of Organic Insulation Material And Insulation System For Exterior Wall Of Building

External wall insulation system(ETICS)is an important part of building engineering,which is an important part of national energy saving and emission reduction.The insulation material bare board in the exterior insulation system and the fire prevention ability of the insulation system are very important to the building safety.At present,in the existing thermal insulation system,organic thermal insulation materials occupy the mainstream position in the thermal insulation materials market,a large number of organic thermal insulation materials are applied to external walls.However,the fire prevention ability of organic insulation materials is relatively weak,and the fire quickly forms vertical three-dimensional fire spread along the external wall,and the lack of effective control and extinguishing means of external wall insulation fire,fire rescue and personnel evacuation difficulties.With the outer protective layer of thermal insulation material damaged or falling off,whether the fire resistance capacity of thermal insulation material and external thermal insulation system can still meet the B1(C)grade refractory grade requirements is related to people’s property safety and life safety.Therefore,we should strengthen the fire prevention ability of external wall insulation materials and insulation system to eliminate potential fire hazards in time.In this paper,the combustion performance of extruded polystyrene board(XPS)and its thermal insulation system,which are widely used in the market,is studied.At present,the test means of extruded polystyrene board by the third party testing laboratory are mainly flammability test of bare board of XPS material and monomer combustion test.There is a lack of means to test the fire performance of damaged extruded polystyrene board materials and assembled thin plastered exterior insulation systems.Therefore,this paper studies the change of fire performance of XPS insulation material under the condition that the ignition surface is cut surface and the ignition surface has cut seam,and further studies the influence of protective layer on the fire performance of XPS insulation material.The research content of this paper is as follows:(1)In the actual construction process of thermal insulation materials,the thermal insulation board pasted at the entrance of the building and the corner of the wall needs to be cut and spliced before being installed in this position.In the installation process of thermal insulation materials,the thermal insulation materials also need to be fixed with expansion plastic anchors,which requires large area drilling and installation of thermal insulation materials.These behaviors will carry out certain damage to the insulation board,which has certain safety risks.In this paper,through comparative test,explore the influence of different ignition on the test results.With reference to the relevant national standards,the combustion performance of bare board and cut thermal insulation materials is studied to explore whether the combustion performance of thermal insulation materials will change after being damaged.The test results show that the flammability test with the ignition surface as the cutting surface and the monomer combustion test with the cutting seam are not ideal.After changing the ignition surface,the fire performance of the extruded polystyrene board fluctuates,which has a certain hidden danger.(2)there is the use of unqualified insulation materials in part of the building,for this part of the building external insulation system has enough fire performance,thin plaster plaster layer mortar can protect the flame retardant ability of the insulation material is ignited is a problem worth studying.In this paper,the extruder board with poor combustion performance is selected to assemble the insulation system,and the single combustion test is carried out to study whether the non-combustible material outside the insulation material can completely block the influence of external fire source on the insulation material.According to the test results,under the influence of continuous external fire source,the internal insulation material melts and shrinks,the drips are reduced,and the performance indexes of combustion performance are reduced.Thin plaster plaster mortar for unqualified insulation material has good protection effect.(3)The insulation system composed of organic insulation materials mainly relies on the thin plastering mortar outside the insulation material to improve the fire prevention ability.At present,the thickness of the plastering layer of most insulation systems is about 3mm ～ 4mm.This paper tests the insulation system with plastering mortar of different thickness by referring to the laboratory test method.The combustion rate growth index,total smoke production and total heat release of insulation systems with different thickness protective layers were compared when they encountered external fire sources,and the influence of coating thickness on the combustion performance of insulation materials was studied.The test results show that the greater the thickness of the plastering layer,the stronger the protection ability of the internal insulation material.