Numerical Simulation And On-site Monitoring Of The Construction Of A Super-tall Building

Super-tall buildings are characterized with unique structural system, difficult structural design and complex constructional process, which pose a great challenge for their constructional process. During constructional stage, the overall structural stiffness, external load and internal stresses are continuously varying, while the structural stress state is complicated. In service stage, the super-tall building may suffer from certain damages due to extreme events, such as typhoons and earthquakes, which would reduce the global structural strength and bring in concerns of structural safety. Therefore, it is of practical significance to combine the finite element model(FEM) and structural health monitoring(SHM) for reliable and efficient evaluation of the structural deformation and stress state of the buildings. Besides, the results are of great use to optimize the constructional programme, thereby assuring the structural safety and improve the constructional efficiency.Firstly, the developments of SHM on high-rise buildings were reviewed and the state-of-the-art of SHM on super-tall buildings was presented. In addition, based on the SHM installed on Shenzhen Pingan Financial Center(PAFC), the full constructional process simulation was conducted and the numerical resul ts were compared with the field data to validate and verify the numerical models. The main contents are as follows:The numerical simulations of vertical cumulative deformations of the concrete core-wall and mega columns in both construction and service st ages were performed. The effects of concrete shrinkage and creep and constructional procedures were investigated. The results indicate that vertical deformation was significantly underestimated in the simulation without considering the shrinkage and creep effects of the concrete and constructional process. Hence, the time-dependent effects of concrete and constructional sequences should be paid special attention in the numerical analysis of vertical deformation of high-rise buildings.The internal forces and stresses of key members of core-wall, mega columns, belt truss and outrigger truss were investigated with the considerations of concrete shrinkage and creep effects. It is found that the time-dependent effects of steel members could not be ignored, which should be taken into accounts in the structural design. The variations of stresses in the cord members of trusses are quite small; on the contrary, these in web members change greatly during the construction process.Through the comparison between on-site measurements and numerical results, a good agreement of vertical deformation and stresses of core-wall and mega columns was found, while some discrepancies existed for steel truss members due to the fact that they are more susceptible to temperature vari ation. The reasons for relatively large errors in some cases may be attributed to environmental factors in the field data acquisition process, which were not included in the numerical simulations, but may greatly impact the on-site measurements. In general, the numerical models developed in this study can provide fairly good agreement with the field data, which can optimize constructional programme and assure the structural safety during both construction and service stages.