Finite Element Analysis and Dynamic Monitoring of High-Altitude Dismantling and Modification Process of Integral Steel Platform

Based on the Xiamen Bailu West Tower project， the whole process of high-altitude dismantling and modification of the integral steel platform was designed for the core tube of the super high-rise tower with an inward-inclined wall. Finite element simulation and dynamic monitoring were also conducted. In this paper， MIDAS Gen was used to carry out the scheme design and finite element simulation for the modification of the integral steel platform passing through the inclined wall， The stress values and levelness of key load-bearing components were dynamically and intelligently monitored throughout the renovation process. According to the oblique retraction of the tower shear wall， a staged dismantling and reinforcement scheme for the integral steel platform formwork system was designed. Finite element calculations were carried out for five key dismantling and modification construction states， with main component parameter values including stress ratio， displacement， and support reaction. The stress distribution and mechanism of the structure under key construction conditions such as formwork lifting， reinforcement binding， and steel platform lifting were thoroughly analyzed. The results showed that the addition of temporary vertical bracing effectively shared the overall load of the structure and reduced the maximum stress ratio. The safety redundancy of the structure after dismantling and modification was higher than that before dismantling and modification， indicating a safer structure. The monitoring revealed that the internal force distribution of the cylinder frame columns， platform beams， and corbels fluctuated within a range lower than the simulation results， and the levelness remained within the early warning value range during climbing. These measures comprehensively ensured construction safety throughout the entire process of integral steel platform modification. This study can provide a reference for the construction and process monitoring of similar super high-rise inclined walls.