Research On Thermal Performance Of ECP Exterior Panel Composite Wall

At present,China is vigorously developing prefabricated buildings.Due to the use of efficient dry construction methods,it can effectively reduce the waste of natural resources and environmental pollution caused by wet operation,which is in line with the development concept of green buildings at this stage.China’s steel production is large,the product variety is relatively abundant,the consumption rate of materials is far less than the production efficiency,and the steel structure building has excellent seismic performance and high safety performance.Promoting the development of steel structure building can make a certain contribution to the sustainable development of China’s construction industry.Because of the large proportion of the external wall in the building envelope,the improvement of the thermal insulation performance of the external wall has a great impact on the building energy saving effect.Therefore,the composite wall construction method matching with the prefabricated steel structure building system is proposed,which can effectively reduce the energy consumption of the building in the use process.The paper focuses on the hollow extruded cement fiber wallboard(ECP wallboard)produced by Tianjin Zhengtong wallboard materials Co.,Ltd.,and studies the construction method of ECP exterior facing composite wall when ECP wallboard is applied to steel structure residential buildings in cold areas.As a non structural decorative panel,ECP wallboard has good fire resistance and sound insulation performance.Because the "Z" type flexible connection is used in the installation process of the wallboard,although it can effectively prevent the wallboard from falling off in the earthquake,there is a hidden danger of thermal bridge at the connection part between the full-length angle steel and the steel members,which reduces the thermal insulation performance of the external wall.Therefore,according to the thermal specification requirements of the exterior wall of residential buildings in cold regions in China,combined with the fluent simulation software and theoretical analysis method,the thermal performance of ECP exterior panel composite wall used in steel structure residential buildings is explored,and a more reasonable ECP exterior panel composite wall structure system is finally determined.Firstly,the product characteristics of hollow extruded cement fiber wallboard are briefly described,and the existing connection modes between lightweight wallboard and steel structure are summarized and analyzed.The "Z" connection construction method suitable for ECP wallboard is determined,and the detailed size and installation process of z-connection are drawn.By comparing and analyzing the advantages and disadvantages of three different forms of wall insulation,this paper puts forward the construction method of ECP exterior panel composite wall insulation suitable for cold areas,and draws the detailed structural drawing of ECP exterior panel composite wall node suitable for steel structure buildings.Secondly,for the cold regions in China,the heat transfer coefficient of ECP exterior panel composite wall is calculated by theoretical calculation and software simulation methods respectively,and the construction method is compared to verify whether it meets the requirements of the code for the limit value of heat transfer coefficient of residential building exterior wall.The results show that the ECP exterior panel composite wall can meet the energy saving design standard of residential buildings in cold regions.By comparing and analyzing the results of manual calculation and software simulation,the effectiveness of the software simulation is verified,which provides technical support for the subsequent thermal bridge simulation analysis.Finally,the software is used to simulate the internal surface temperature of the thermal bridge node to analyze whether the surface condensation will occur,and to determine the optimal solution of the insulation material,insulation layer thickness and air interlayer thickness in the ECP exterior panel composite wall structure.In order to change the thickness of interlayer from 50 mm to 80 mm,rock wool board,glass wool board,EPS board,polyurethane board and XPS board were selected;By changing the thickness of the insulation board from 0 mm to 80 mm,the other components of the wall remain unchanged.The thermal bridge structure under different working conditions is simulated and analyzed,and the economic and reasonable reference value is given.Hollow extruded cement fiber wallboard is a kind of lightweight decorative wallboard,with excellent fire resistance and sound insulation performance.Dry installation method is adopted,with high construction efficiency and less pollution to the environment.Research on ECP exterior decorative panel composite wall for prefabricated steel residential buildings in cold areas is carried out to provide a complete set of composite wall construction methods,It can provide a theoretical basis for the popularization and application of ECP wallboard and the development of prefabricated steel residential buildings.