Analysis And Construction Technology Research Of Key Systems Of Intelligent Construction Machine For Super High-rise Buildings

The development of intelligent construction machine is in line with the requirements of promoting the development of intelligent construction technology in China’s "14th Five-Year Plan".In recent years,the jacking system independently developed by our technical staff has been successfully applied in many projects,however,although the jacking system has the trend of intelligent construction,it cannot adapt well to the core cylinder wall the increase of height and large changes of cross-sectional form,which makes it difficult to select the support points in high altitude,and it is difficult to realize the assembly type installation of steel truss,the whole life cycle health monitoring and the goal of "demolition plus balance" when dismantling and changing at high altitude.Therefore,the new mold construction equipment-intelligent construction machine was born at this time.In this paper,the key systems of the intelligent construction machine were selected and designed,numerically analyzed,and the installation and construction simulations and field tests were carried out in a super high-rise project in Xi’an,and an assembled lightweight intelligent construction machine was designed based on the numerical analysis results.The safety of the intelligent construction machine in engineering applications is guaranteed from design and calculation,installation and construction to field test in all aspects,as follows:(1)Based on the systematic review of domestic and foreign literature,the functions and characteristics of each component system of the intelligent construction machine are clarified and its working principle is elucidated,the selection analysis of key systems is focused,and the key systems of the intelligent construction machine are designed according to the characteristics of the building structure and the important and difficult points faced by the design with a super highrise project in Xi’an as the background,and the process flow of the standard floor construction is given.(2)Combining with the actual project and the existing relevant codes and standards,the load values and combination principles of the key system of the intelligent construction machine under the three operation stages are determined,and numerical analysis is carried out to investigate the safety of the structure under the two limit states of load carrying capacity and normal use.From the analysis results of the calculated length coefficient method,it can be seen that the strength,stiffness and stability of the key system of the intelligent construction machine under the three operation stages meet the requirements of the steel structure design standard;from the calculation results of the direct analysis method,it can be seen that the stress and vertical displacement of the structure after adding the initial defects meet the steel structure design standard,but its ultimate bearing capacity decreases by 17.6%,in order to ensure the safety,the nonlinear buckling should be used as the ultimate load capacity.In order to ensure safety,the results of the analysis should be used as the limit value for the design of the structural stability bearing capacity.Based on the results of numerical analysis,an optimized mathematical model was established to improve the design of steel joist,and the safety of the improved structure was verified by using the direct analysis method,and finally,an assembled lightweight intelligent construction machine with 15.04% less steel was obtained.(3)The finite element software was used to carry out the lifting verification of the key components of the intelligent construction machine,and the installation and construction process of the key system of the intelligent construction machine was simulated by the "life and death unit method",and the analysis results showed that the stress and accumulated deformation of the components during the installation and construction process were in accordance with the requirements,which verified the feasibility of the installation and construction plan.(4)A field test study was conducted on the steel truss members at key locations,and the actual stress curves of the key members under three operation stages of jacking,construction and lifting were obtained.The test results show that the safety reserve of the members at each measurement point under the three operation stages is high and the overall operation of the structure is safe and reliable,and the stress change trend matches with the results obtained from numerical analysis,indicating that the established finite element model can better reflect the stress situation of the key system of the intelligent construction machine.