Research On The Thermal Effect Of The Ultra-long And Ultra-wide Steel Structure Factory Under Solar Radiation

With the rapid development of China’s manufacturing industry,steel structure industrial factories are came into beings,an increasing number of ultra-long and ultra-wide steel structure factories meeting different functional requirements.Since steel is sensitive to the temperature response under solar radiation,it is of great significance to study the thermal effect of the main body and the enclosure structure of the ultra-long and ultra-wide steel structure in the construction process due to the non-uniform temperature of solar radiation.Based on the ultra-long and ultra-wide steel structure factory of Shenyang Huachen BMW Automobile Co,Ltd,in this paper the research and development status of large-span steel structure under solar radiation at home and abroad are summarized and analyzed.Through numerical simulation,the non-uniform temperature field and thermal effect of the main structure and envelope structure of the ultra-long and ultra-wide steel structure factory building under solar radiation during the construction are studied and analyzed.The main research contents and results are as follows:(1)The calculation model of temperature field and temperature effect are established,and temperature field parameters is analyzed.Based on the calculation theory of thermal effect,the influence of different parameter conditions on the surface temperature of H-shaped steel is analyzed,and selected the wind speed conditions to study the influence of the temperature on the main structure and the surface temperature of the enclosure structure during the construction of an ultra-long and ultra-wide industrial factory.The results show that,as the wind speed increases,the surface temperature of the structure gradually decreases.When the wind speed increases from 1m/s to 5m/s,the maximum temperature of the structure surface decreases by 12.1% and13.8% on average.It can be seen that,during the construction process,it is beneficial to the decrease of component surface temperature and non-uniformity of structure surface temperature under sunshine by properly ventilation.(2)The numerical simulation of the temperature field of the ultra-long and ultra-wide steel structure factory is conducted,and the variation law of the non-uniform temperature field of solar radiation during the construction period of the main body and the envelope of the ultra-long and ultra-wide steel structure factory is obtained.Under the non-uniform temperature field of solar radiation,the temperature of the main structure and the surface of the enclosure structure shows approximately sinusoidal changes at different times of the day,that the highest temperature appears at 2 p.m in the day,the highest temperatures being 61.1℃ and 63.0℃,respectively.;The maximum temperature difference between the surface temperature of the two-stage structure and the air can reach as high as 30.1℃ and 32.0℃;the temperature difference between the facing surface and the backlight surface is constantly changing,and the maximum temperature difference can reach 21.0℃ and 21.6℃.The inhomogeneity of structure surface is relatively high.(3)Through numerical simulation analysis,the thermal effect distribution and change law of the main body of the ultra-long and ultra-wide steel structure factory and the enclosing structure during the construction process are obtained.The results show that there is a significant positive correlation between the maximum stress and maximum deformation of the structure under the non-uniform temperature field of solar radiation and the temperature of the surface of the structure.The changing trend is sine curve,and the maximum value appears at 2 p.m;The maximum deformation of the protective structure is 15.7mm and 48.3mm,and the maximum stress is 57.1MPa and 122.0MPa,respectively.The thermal effect is obvious.Therefore,security measures should be taken at the place of large displacement and stress during construction.(4)Using finite element software,the optimal closing temperature of the roof of the enclosure structure is determined.Numerical simulation is carried out on whether the construction temperature should be considered when the ultra-long and ultra-wide steel structure factory is closed,and selection of optimum closure temperature of structure.The results show that the selection of the closing temperature needs to consider the influence of the installation temperature.Through the variation of internal force of the structure with closure temperature under two extreme temperatures,and considering the influence of construction factors comprehensively,the optimal closure temperature of the envelope roof of this project is determined as 13℃ ± 5℃.