Research on Analysis Method of Mechanical Properties of Modular Steel Frame Based on Multi-Scale and Beam Elements

In order to explore the analysis method and applicability of prefabricated modular steel frame structures, the multi-scale finite element model is established in the ABAQUS finite element software to analyze static and dynamic characteristic. The static characteristic of beam element, solid element and multi-scale joint calculation models are compared and analyzed. The differences of beam element, solid element and multi-scale frame calculation model are compared from two aspects of internal force analysis and model analysis of modular structure. In addition, the multi-scale model is applied to the dynamic elastic-plastic time history analysis of the modular steel frame structure, and the dynamic response differences between the beam element and the multi-scale frame 6 to 12-story model are compared and analyzed. The results show that internal multi-point constraint method in ABAQUS can achieve the connection between beam element and solid element; the calculation accuracy of the multi-scale model is in good agreement with that of the solid element. Comparing the two models, the multi-scale calculation model can increase the calculation efficiency by about 40%; the dynamic modal analysis shows that the natural frequencies of the multi-scale model and the solid element are basically the same, which verifies the reliability of the multi-scale model calculation results; when the number of modular structure floors exceeds 10, the calculation accuracy of the beam element calculation model is greatly reduced, while the calculation accuracy of the multi-scale calculation model is stable.