• Steel and Composite Structures
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• v.23 no.2
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• pp.173-186
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• 2017

Conceptual configuration and seismic performance of high-rise steel frame-brace structure are studied. First, the topology optimization problem of minimum volume based on truss-like material model under earthquake action is presented, which is solved by full-stress method. Further, conceptual configurations of 20-storey and 40-storey steel frame-brace structure are formed. Next, the 40-storeystructure model is developed in Opensees. Two common configurations are utilized for comparison. Last, seismic performance of 40-storey structure is derived using nonlinear static analysis and nonlinear dynamic analysis. Results indicate that structural lateral stiffness and maximum roof displacement can be improved using brace. Meanwhile seismic damage can also be decreased. Moreover, frame-brace structure using topology optimization is most favorable to enhance lateral stiffness and mitigate seismic damage. Thus, topology optimization is an available way to form initial conceptual configuration in high-rise steel frame-brace structure.

• International Journal of High-Rise Buildings
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• v.4 no.1
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• pp.75-83
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• 2015

In the present study, the preliminary results of a large-scale seismic response analysis of a super-high-rise steel frame considering soil-structure interaction are presented. A seismic response analysis under the excitation of the JR Takatori record of the 1995 Hyogoken-Nanbu earthquake is conducted. Precise meshes of a 31-story super-high-rise steel frame and a soil region, which are constructed completely of hexahedral elements, are generated and combined. The parallel large-scale simulation is performed using K computer, which is one of the fastest supercomputers in the world. The results are visualized using an offline rendering code implemented on K computer, and the feasibility of using a very fine mesh of solid elements is investigated. The computation performance of the analysis code on K computer is also presented.

• International Journal of High-Rise Buildings
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• v.3 no.3
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• pp.205-214
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• 2014

The super high rise building construction is characterized by a large quantity of engineering works and structural components, high demanding of construction technology and complex cross operations. As the height of super high rise building increases, the construction difficulties increase, it is challenging the steel structural building construction technology. In this paper, the key technologies in the construction of Chinese modern super high rise steel structure building have been studied. The innovative tower crane supporting frame suspension disassembly technology has been developed to allow the crane supporting frame to turnover in the air without occupying materials stockyard. A new self-elevating platform technique which is capable of striding over structural barriers has been developed. This new technology allows the platform to be self-elevated along variable cross section column with a maximum 600 mm size change. A new automatic submerged arc welding technology has also been developed to ensure the process continuity and quality stability of welding job on the construction site.

• Steel and Composite Structures
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• v.18 no.1
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• pp.121-134
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• 2015

This paper is to investigate the potentials of the elastic seismic design of twisted high-rise steel diagrid frame buildings in the strong wind and moderate/low seismicity regions. First, the prototypes of high-rise steel diagrid frames with architectural plans that have a twist angle of 0 (regular-shaped), 1, and 2 degrees were designed to resist wind. Then, the effects of the twist angle on the estimated quantities and structural redundancies of the diagrid frames were examined. Second, the seismic performance of the wind-designed prototype buildings under a low seismicity was evaluated. The response spectrum analysis was conducted for the service level earthquake (SLE) having 43-year return period and the maximum considered earthquake (MCE) having 2475-year return period. The evaluation resulted that the twisted high-rise steel diagrid frames resisted the service level earthquake elastically and most of their diagrid members remained elastic even under the maximum considered earthquake.

• International Journal of High-Rise Buildings
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• v.4 no.3
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• pp.171-180
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• 2015

A shaking table test was conducted at the E-Defense shaking table facility to investigate the damage and collapse behavior of a steel high-rise building under exceedingly large ground motions. The specimen is a one-third scale 18-story steel moment frame designed and constructed according to design specifications and practices used in the 1980s and 1990s. The shaking table tests used a long-duration, long-period ground motion simulated for a sequential Tokai, Nankai, and Nankai earthquake scenario. The building specimen was subjected to a series of progressively increasing scaled motions until it completely collapsed. The damage to the steel frame began through the yielding of beams along lower stories and column bases of the first story. After several excitations by increasing scaled motions, cracks initiated at the welded moment connections and fractures in the beam flanges spread to the lower stories. As the shear strength of each story decreased, the drifts of lower stories increased and the frame finally collapsed and settled on the supporting frame. From the test, a typical progression of collapse for a tall steel moment frame was obtained, and the hysteretic behavior of steel structural members including deterioration due to local buckling and fracture were observed. The results provide important information for further understanding and an accurate numerical simulation of collapse behavior.

• Structural Engineering and Mechanics
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• v.71 no.4
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• pp.417-432
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• 2019

Seismic performance analysis of steel-brace reinforced concrete (RC) frame using topology optimization in highly seismic region was discussed in this research. Topology optimization based on truss-like material model was used, which was to minimum volume in full-stress method. Optimized bracing systems of low-rise, mid-rise and high-rise RC frames were established, and optimized bracing systems of substructure were also gained under different constraint conditions. Thereafter, different structure models based on optimized bracing systems were proposed and applied. Last, structural strength, structural stiffness, structural ductility, collapse resistant capacity, collapse probability and demolition probability were studied. Moreover, the brace buckling was discussed. The results show that bracing system of RC frame could be derived using topology optimization, and bracing system based on truss-like model could help to resolve numerical instabilities. Bracing system of topology optimization was more effective to enhance structural stiffness and strength, especially in mid-rise and high-rise frames. Moreover, bracing system of topology optimization contributes to increase collapse resistant capacity, as well as reduces collapse probability and accumulated demolition probability. However, brace buckling might weaken beneficial effects.

• Steel and Composite Structures
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• v.39 no.1
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• pp.65-80
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• 2021

Irregularities of a building in plan and elevation, which results in the change in stiffness on different floors highly affect the seismic performance and resistance of a structure. This study motivated to investigate the seismic responses of high-rise steel-frame buildings of twelve stories with various stiffness irregularities. The building has five spans of 3200 mm distance in both X- and Z-directions in the plan. The design package SAP2000 was adopted for the design of beams and columns and resulted in the profile IPE500 for the beams of all floors and box sections for columns. The column cross-section dimensions vary concerning the number of the story; one to three: 0.50×0.50×0.05m, four to seven: 0.45×0.45×0.05 m, and eight to twelve: 0.40×0.40×0.05 m. Real recorded ground accelerations obtained from the Vrancea earthquake in Romania together with dead and live loads corresponding to each story were considered for the applied load. The model was validated by comparing the results of the current method and literature considering a three-bay steel moment-resisting frame of eight-story height subject to seismic load. To investigate the seismic performance of the buildings, the time-history analysis was performed using ABAQUS. Deformed shapes corresponding to negative and positive peaks were provided followed by the story drifts and fragility curves which were used to examine the probability of collapse of the building. From the results, it was concluded that regular buildings provided a seismic performance much better than irregular buildings. Furthermore, it was observed that building with torsional irregularity was more vulnerable to seismic failure.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.1
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• pp.53-63
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• 2009

Use of high-strength steel members in building of high-rise buildings and large scale structures is expected to increase the effectiveness of structural design by reducing the weight and cost of structures. So far, high-strength steel members have been used in a very limited way because it is hard to select the proper strengths of steel members in a systematic way with the consideration of the structural cost. In this paper, therefore, a structural optimization technique based on Genetic algorithm is developed for effective use of high-strength steel members in structural design of high-rise buildings with the form of building frame system. The stability and efficiency of the technique is evaluated by using to a 35-story building. As a result, a stable and reliable optimal solution was obtained with a difference of 2.63% between individual and mean optimal structural costs.

• International Journal of High-Rise Buildings
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• v.1 no.4
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• pp.271-281
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• 2012

Tianjin Goldin Finance 117 tower has an architectural height of 597 m, total of 117 stories, and the coronation of having the highest structural roof of all the buildings under construction in China. Structural height-width ratio is approximately 9.5, exceeding the existing regulation code significantly. In order to satisfy earthquake and wind-resisting requirements, a structure consisting of a perimeter frame composed of mega composite columns, mega braces and transfer trusses and reinforced concrete core containing composite steel plate wall is adopted. Complemented by some of the new requirements from the latest Chinese building seismic design codes, design of the super high-rise building in high-intensity seismic area exhibits a number of new features and solutions to professional requirements in response spectrum selection, overall stiffness control, material and component type selection, seismic performance based design, mega-column design, anti-collapse and stability analysis as well as elastic-plastic time-history analysis. Furthermore, under the prerequisite of economic viability and a series of technical requirements prescribed by the expert review panel for high-rise buildings exceeding code limits, the design manages to overcome various structural challenges and realizes the intentions of the architect and the client.

• Journal of the Korean Solar Energy Society
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• v.33 no.3
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• pp.51-57
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• 2013

Metal curtain wall systems are widely used in high-rise commercial and residential buildings. While aluminum is the most frequent used frame material, steel framing is also reemerging as a high-performance material in glazed curtain walls due to less thermal conductivity and design flexibility. The purpose of this study is to evaluate thermal performance of a steel frame curtain wall system by comparing with a aluminum frame curtain wall system. The thermal transmittance was measured according to KS 2278, and condensation resistance was calculated by the test results according to KS F 2295. The steel framing test specimen showed lower thermal transmittance and temperature descending factor compared to the aluminum framing test specimen.