Non-uniform temperature field and effects of large-span spatial truss structure under construction: Field monitoring and numerical analysis

The large-span spatial truss structure under construction can produce significant non-uniform temperature effect due to strong solar radiation, and it directly affects the quality of structural closure and even leads to potential safety hazards. In order to study the non-uniform temperature field, the steel roof of Xi'an Silk Road International Convention and Exhibition Center under construction was selected as the studied structure, the real-time temperatures of test points and thermal boundary conditions were monitored for 30 days. The numerical simulation method of temperature field of spatial truss structure was established considering real-time shadow effect, which can be effectively analyzed by the proposed shadow analysis algorithm. During monitoring period, the structural temperature field under strong solar radiation is significantly non-uniform with maximum temperature difference between test points of 15.6℃, and the maximum temperature rise of test point compared with atmospheric temperature is 16.9℃. By comparison with test results, the accuracy of numerical method is verified, and the daily root mean square of error rates for all monitored members is lower than 6.5% during the monitoring period. Through the analysis of test and simulation results, the non-uniform features of temperature field of large-span spatial truss structure was studied. In addition, the temperature effect was calculated for different healing times considering non-uniform temperature field of large-span spatial truss structure under construction. Then some construction suggestions for healing time were also given. The research method and conclusions of this paper can provide valuable references for thermal design, monitoring and control of large-span spatial truss structure.