Analysis And Research On The Overall Lifting Construction Process Of A Towering Closed Cantilevered Steel Structure

In recent years,with the continuous development of radio,communication,television and tourism,various types of towering structures have emerged.As a kind of high tower that attracts tourists,sightseeing towers have become landmark buildings in major cities.The needs of various purposes such as radio and television,tourism,environmental monitoring and meteorological monitoring require the construction of a large-scale "sky pavilion" at the top of the sightseeing tower,but this makes the structure more difficult to construct.It is particularly important to carry out simulation analysis and on-site monitoring of the lifting process.This paper takes the Beijiang Pearl Tower revolving restaurant project as the research object,conducts on-site monitoring and finite element simulation analysis for the entire construction process of the revolving restaurant,and focuses on the following research:(1)The engineering overview of the Beijiang Pearl Tower and the construction plan for the lifting process of the revolving restaurant were introduced in detail,and the ABAQUS finite element analysis software was used to simulate the various construction processes of the revolving restaurant,the stress and displacement changes of the structure during the construction of the revolving restaurant are analyzed.(2)According to the numerical simulation analysis results of Beijiang Pearl Tower by finite element software,a monitoring plan was formulated,and the structure was monitored from the aspects of stress and displacement.The results showed that the structure was within the allowable range of the specification in terms of stress and displacement.The accuracy of the finite element simulation is verified by comparing and analyzing the simulation data and monitoring data objects.(3)Aiming at the influence of the asynchronous lifting of the rotating restaurant on the structure,the finite element software is used to simulate the lifting process of the structure,and the stress and displacement change laws of important parts such as steel strands and rotating restaurants are discussed respectively,furthermore,the influence of the position of the asynchronous lifting point,the speed difference,and the cross-sectional area of the steel strand on the structural stress and displacement was further studied.The results show that the influence of the asynchronous lifting point on the structure will increase with time and cause serious damage;The speed difference and the cross-sectional area of the steel strand both affect the unsynchronized degree of structural lifting,which in turn affects the internal force of the structure.(4)Use the life-death element technology to analyze the possible failure of components in the process of structural lifting,and discuss the influence of the individual failure of each component of a certain frame of the revolving restaurant on the structural stress and displacement.The study found that the failure of components at the lifting point has the greatest impact on the structure,further,the influence of the composite failure of the components near the lifting point on the structure is studied.The results show that the simultaneous failure of unconnected members of the same type has a greater impact on the structure than the simultaneous failure of connected members of the same type,and the degree of influence decreases with the increase of the distance between the failed components;Simultaneous failure of different kinds of components has a greater impact on the structure than the superposition of single component failures.(5)The influence of different unloading sequences on the structure is discussed from the maximum stress of the structure and the stress change of key components.The results show that when the temporary support is unloaded,the secondary members other than the layer where the lifting point of the hoisting steel strand is located should be removed first,then the steel strand is gradually removed,and finally the main supporting members near the upper and lower hanging points of the steel strand are removed.