Analysis of modal characteristics and strengthening effect of truss roof

The modal characteristics are an important basis for measuring the stability and safety of the truss roof structure. Based on the finite element method, the modal calculation of the overall structure of the truss roof was carried out, and the first six-order modal shapes and natural frequencies were obtained. The modal test method was adopted to test and analyze the vibration response of the truss roof through the hammering method, verifying the accuracy and effectiveness of the modal simulation. According to the analysis results of the modal shapes, the structure was reinforced at the weak positions. The thickness of the end face was reduced by 1 mm, and five ribs at the connection between the panel and the lateral beam were add. Through the modal calculation, the dynamic response of the optimized structure was obtained. The results show that the optimized structure can significantly increase the natural frequency, reduce the vibration amplitude, avoid the low-frequency resonance problem, and meet the lightweight design requirements at the same time, which is of obvious help for the improvement of the truss performance.