The Structural Design of Tall and Special Buildings

Koutsoloukas, Lefteris; Nikitas, Nikolaos; Aristidou, Petros

doi: 10.1002/tal.1941pmid: N/A

In this paper, the robust control of a real high‐rise tower is studied, using a newly proposed, in the structural control field, Robust Model Predictive Control scheme (RMPC). Two RMPC controllers were designed considering either displacement mitigation (RMPC1) or power consumption efficiency (RMPC2). The two controllers were compared to the benchmark, robustness‐wise, H∞ control scheme to demonstrate their relative performance. A number of stiffness and damping uncertainty scenarios were designed based on a broad study of the relevant literature, in order to estimate the robustness of each of the three controllers. In all scenarios, variable actuator uncertainty of ±5% was introduced. It was found that all controllers are effective in controlling the tower and demonstrate robustness against parametric and actuator uncertainties with different relative merits over each other. Indicatively, when considering root‐mean‐square (RMS) and peak displacement and acceleration reduction, the H∞ had an average performance reduction of 24%, the RMPC1 31% and the RMPC2 28% against their uncontrolled equivalent.

doi: 10.1002/tal.1875pmid: N/A

No abstract is available for this article.

Wang, Yuanhang; Zhou, Yingmin; Zhu, Liming; Zhang, Tongsheng; Jia, Baiqu; Han, Song; Lu, Zheng

doi: 10.1002/tal.1943pmid: N/A

Due to creep and shrinkage of concrete, the long‐term structural deformation is one of the hottest topics in the study of super high‐rise structures. For the frame–eccentrical core tube structure, its long‐term deformation includes both vertical deformation and obvious horizontal deformation, which will have an inevitable influence on the structural verticality. The horizontal deformation and its formation mechanism in frame–eccentrical core tube structure are studied in this paper. Based on the finite element software ETABS, a refined finite element model combining with the time‐dependent material model of concrete is established base on a subsistent structure. According to the actual construction conditions, construction analysis is conducted, and the construction deformation and the long‐term deformation after completion are subsequently studied. Based on the results of construction analysis, the effects of elastic modulus, creep, and shrinkage on structural horizontal deformation are analyzed; furthermore, the horizontal deformation characteristics of different structural members in different periods are compared. The results show that the horizontal deformation is related to the vertical deformation of the component, and creep and shrinkage exert opposite effects on the structural horizontal deformation. Besides, the creep and shrinkage are the dominant factors of the horizontal deformation in the later stage. These results are supported by real deformation data obtained from real‐time deformation monitoring during construction, which proves the effectiveness of the method adopted in this paper.

Twizere, Moussa; Taşkın, Kivanc

doi: 10.1002/tal.1940pmid: N/A

Box steel columns have significant advantages compared with H‐columns. However, box steel columns have the detrimental tendency of developing a plastic hinge at the column panel zone due to stress concentration. One of the methods for moving the concentration of the stresses at the column panel zone is to use a reduced beam. Nevertheless, a reduced beam decreases the capacity of the beam. This paper proposes a solution to the plastic hinge location without reducing the capacity of the beam. In this study, 106 connection configurations were numerically investigated using ABAQUS software. Two relevant experimental studies were used to validate the modeling techniques. The proposed joint was classified as semi‐rigid and full strength according to Eurocode‐3. To predict the cyclic behavior of the proposed connection, analytical simulation was performed using a Matlab program that uses the Richard and Abbot function. The program was able to accurately reproduce the connection behavior. Through parametric studies, the influence of plate thickness, column, and beam geometry on the connection's initial stiffness and moment resistance was examined. Finally, by using regression analysis, linear functions capable of predicting the initial stiffness and moment resistance of the connection were proposed.

Zhenyun, Tang; Xiaohui, Dong; Zhenbao, Li; Xiuli, Du

doi: 10.1002/tal.1942pmid: N/A

With combination of physical experiment and numerical simulation, real‐time hybrid simulation (RTHS) can enlarge the dimensions of testing specimens and improve the testing accuracy. However, due to the limitation of computing capacity, the maximum degrees of freedom for numerical substructure are less than 7000 from the reported RTHS testing. It cannot meet the testing requirements for evaluating the dynamic performance of large and complex engineering structures. Taking advantages of parallel computing toolbox (PCT) in Matlab and high‐performance computing of graphics processing unit (GPU). A RTHS framework based on MATLAB and GPU was established in this work. Using this framework, a soil‐structure interaction system (SSI) was tested by a shaking table based RTHS. Meanwhile, the dynamic response of this SSI system was simulated by finite element analysis. The comparison of simulation and testing results demonstrated that the proposed testing framework can implement RTHS testing successfully. Using this method, the maximum degrees of freedom for numerical substructure can reach to 27,000, which significantly enhance the testing capacity of RTHS testing for large and complex engineering structures.