Monitoring and Analysis of Lifting Process of High-Altitude Conversion Steel Truss Structure

As a lightweight and high-strength structural system, steel truss has excellent seismic performance. The application of steel trusses to the conversion layer of residential buildings can greatly improve the seismic capacity of the entire residential structure and provide a safer living environment. Compared with the traditional concrete structure, it is more lightweight, less self-weight, has faster construction speed and can achieve large-span column-free design, provide more flexible spatial layout, and improve space utilization. Therefore, steel trusses are widely used in modern residential structures. However, due to the huge volume of steel trusses and the high precision requirements for lifting, the lifting operation is facing great challenges. At present, there are relatively few systematic and normative studies in the field of high-rise steel truss lifting. Therefore, it is necessary to study the stress and deformation of key parts of steel truss in the lifting process, so as to provide scientific basis and guidance for the lifting process, improve work efficiency and safety.
Based on the steel truss transfer floor project of Qinhuangdao Jinmeng Bay Phase II residential building, this paper establishes an accurate three-dimensional finite element model through the finite element software ABAQUS. The lifting points are set at both ends of the steel truss, and the constraint mode is hinged. The lifting scheme of the project is simulated and analyzed. Through the finite element simulation, the stress and deformation of the steel truss in the lifting process can be simulated, which provides a basis for the selection of measuring points in the key parts of the construction process. The stress and strain of the key components in the lifting process are monitored in real time, and the simulation results are compared with the actual monitoring data. The results show that the maximum stress obtained by simulation is located near the left hanging point of the second truss. The stress level of the whole truss component is much lower than the yield stress of the component, and the steel truss has sufficient strength to resist the load. The maximum vertical deformation is located in the middle of the truss span and meets the requirements of the engineering code. The deformation of the steel truss is controlled within a reasonable range. In the process of lifting, different lifting points are subjected to different lifting reactions. The lifting points with large lifting reactions will cause the hydraulic cylinder in the hydraulic system to respond differently when subjected to pressure, resulting in asynchronous lifting stress, causing stress concentration at the lifting point, but its stress is still within the safe range; real-time monitoring of the truss lifting process can accurately obtain the stress and deformation of the key parts, which is convenient for fine-tuning during the lifting process and ensures the safety and accuracy of the lifting. The monitoring value is slightly smaller than the simulation value, and the actual lifting of the project is safer than the simulation analysis. The accuracy of the finite element analysis and the lifting scheme is verified, which provides useful experience for improving the safety and stability of the project and provides reference for subsequent similar projects.