• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.363-368
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• 2006

The purpose of this case study is to analyze stack effect problems and to develop methods minimizing methods of stack effect in the tall complex building in cold climates. The main problems in the tall complex building occur in high-rise elevators. Such problems as elevator doors that do not close and exhaust airflows result in excessive pressure differences across elevator doors due to stack effect. Under the expected conditions causing these pressure differences, computer simulations with CONTAMW computer program and field measurements are performed in the tall complex building. The results are analyzed in architectural design aspects. With these analysis, the tall complex building design guidelines to minimize stack effect are proposed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.2
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• pp.118-125
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• 2009

The purpose of this study is to evaluate the stack effect reduction alternatives in tall complex buildings in cold climates. The main problems in tall buildings occur in elevators. Such problems as elevator doors that do not close and exhaust airflows result in excessive pressure differences across elevator doors due to stack effect. Under the expected conditions causing these pressure differences, Field measurements are performed in three tall buildings. Each result of the measurements is analyzed in architectural design aspects. With these analysis, building design guidelines are proposed and analyzed by field measurements and computer simulations.

• International Journal of High-Rise Buildings
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• v.5 no.4
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• pp.243-250
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• 2016

Today's architectural design trend based on the recognition of pluralism has led to multiple design directions for all building types including tall buildings. This contemporary design trend has produced many complex-shaped tall buildings, such as twisted, tilted, tapered and freeform towers. Among many different structural systems developed for tall buildings, the diagrid system, with its powerful structural rationale and distinguished aesthetic potential, is one of the most widely used systems for today's tall buildings. This paper studies structural performance of diagrid systems employed for complex-shaped tall buildings. Twisted, tilted, tapered and freeform tall buildings are designed with diagrid structures, and their structural performances are investigated. For the twisted diagrid study, the buildings are twisted up to 3 degrees per floor. In the tilted diagrid study, the angles of tilting range from 0 to 13 degrees. The impact of eccentricity is investigated for gravity as well as lateral loads in tilted towers. In the study of tapered diagrid structures, the angles of tapering range from 0 to 3 degrees. In the study of freeform diagrid structures, lateral stiffness of freeform diagrids is evaluated depending on the degree of fluctuation of free form. The freeform floor plans fluctuate from plus/minus 1.5 meter to plus/minus 4.5 meter boundaries of the original square floor plan. Parametric structural models are generated using appropriate computer programs and the models are exported to structural engineering software for design, analyses and comparative studies.

• International Journal of High-Rise Buildings
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• v.5 no.1
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• pp.13-20
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• 2016

Today's architecture can be best understood only through the recognition of pluralism, and, as is true of other building types, multiple design directions are prevalent for tall buildings. This contemporary design trend has produced many complex-shaped tall buildings, such as twisted, tilted and tapered form towers. Among many different structural systems developed for tall buildings, the outrigger system, with its inherent structural efficiency and flexibility in façade design, is widely used for contemporary tall buildings. This paper studies structural performance of outrigger systems employed for complex-shaped tall buildings. Twisted, tilted and tapered tall buildings are designed with outrigger structures, and their structural performance is investigated. For the twisted outrigger study, the buildings are twisted up to 3 degrees per floor. In the tilted outrigger study, the angles of tilting range from 0 to 13 degrees. The impact of eccentricity is investigated for gravity as well as lateral loads in tilted towers. In the study of tapered outrigger structures, the angles of tapering range from 0 to 3 degrees. Parametric structural models are generated using appropriate computer programs for these studies, and the models are exported to structural engineering software for design and analyses.

• International Journal of High-Rise Buildings
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• v.3 no.3
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• pp.191-198
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• 2014

The tall building and super tall building has been a common building type in China, with multiple functions and complex geometry. Composite construction is broadly used in tall building structures and constitutes the mixed structure together with concrete and steel constructions. The mixture of the constructions is purposely designed for specific area based on the analysis results to achieve the best cost-effectiveness. New types of composite construction are conceived of by engineers for columns and walls. Material distribution is more flexible and innovative in the structural level and member level. However the reliability of computer model analysis should be verified carefully. Further researches in the design and build of composite construction are necessary to ensure the success of its application. Composite or Mixture Index is suggested to be used as a performance benchmark.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.35-36
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• 2011

Recently, an irregular-shaped super tall building has been increased, aiming toward landmarks of cityscape. However, the complex floor plan derived from an irregular shape requires considerable resources including time, cost, and effort to meet complex structural framework. Based on the motivation, the study proposes a table-form system that is variable slab form appropriate to an irregular shaped floor through improving limitations of an existing table-form system. The variable table-form is expected to reduce construction resources and improve constructability on an irregular floor plan of super tall buildings as well.

• International Journal of High-Rise Buildings
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• v.4 no.1
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• pp.1-8
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• 2015

A team of researchers and practitioners were recently assembled to prepare a monograph on "Wind-Induced Motion of Tall Buildings: Designing for Habitability". This monograph presents a state-of-the-art report of occupant response to wind-induced building motion and acceptability criteria for wind-excited tall buildings. It provides background information on a range of pertinent subjects, including: ${\bullet}$ Physiological, psychological and behavioural traits of occupant response to wind-induced building motion; ${\bullet}$ A summary of investigations and findings of human response to real and simulated building motions based on field studies and motion simulator experiments; ${\bullet}$ A review of serviceability criteria to assess the acceptability of wind-induced building motion adopted by international and country-based standards organizations; ${\bullet}$ General acceptance guidelines of occupant response to wind-induced building motion based on peak acceleration thresholds; and ${\bullet}$ Mitigation strategies to reduce wind-induced building motion through structural optimization, aerodynamic treatment and vibration dissipation/absorption. This monograph is to be published by the American Society of Civil Engineers (ASCE) and equips building owners and tall building design professionals with a better understanding of the complex nature of occupant response to and acceptability of wind-induced building motion. This paper is a brief summary of the works reported in the monograph.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.171-172
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• 2013

An operation planning of lift car is crucial in tall building construction especially it's arrangement plans, because it is related with transportation distance of finishing materials affecting construction productivity. Since tall building construction, composed of complicating and huge plane have complex traffic lines of finishing materials, to determine the position of lift car empirically or intuitively has limits. Therefore this paper suggest an optimum layout model of lift car minimizing the transportation distance both at site-level and floor-level using Graph theory and Dijkstra algorithm.

• Journal of Korean Association for Spatial Structures
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• v.6 no.2 s.20
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• pp.77-83
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• 2006

The planning process of complex projects in tall building is characterized by the cooperation of many involved specialists and by a high degree of information exchange. In order to improve the quality of the structural design of tall buildings, information of different involved partners in the planning process has to be integrated. This paper aims to introduce a concept of the integrated structural design for the tall building using STEP(Standard for the Exchange of Product Model Data). In this study, the entities of mass, column shortening, and serviceability evaluation for structural design in tall buildings are proposed.

• Journal of Korean Association for Spatial Structures
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• v.11 no.4
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• pp.79-88
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• 2011

Recently, complex-shaped tall buildings represented by 3T(Twisted, Tapered, Tilted) are planed largely. A diagrid structural system is one of the most widely used structural system for complex-shaped tall buildings because of its structural efficiency and formativeness. Plans for tilted tall buildings are largely presented because of beauty of a sculpture and many of buildings use diagrid structural systems. Lateral displacements of tilted tall buildings are induced by not only lateral loads but also self weight. Therefore, reduction of lateral responses of tilted tall buildings is as important as typical tall buildings. In this study, a smart TMD is introduced to reduce seismic responses of tilted diagrid tall buildings and its control performance is evaluated. MR damper is employed for the smart TMD and ground-hook controller is used as a control algorithm for the smart TMD. 100-story tall building is used as an example structure. Control performances of uncontrolled case, controlled case with TMD and controlled case with smart TMD are compared and investigated. Numerical simulation has shown that smart TMD presented good control performance for displacement response but acceleration response was not controlled well.