Strength Evaluation for Cap Plate on the Node Connection in Circular Steel Tube Diagrid System

Lee, Seong-Hui,Kim, Jin-Ho,Choi, Sung-Mo Council on Tall Building and Urban Habitat Korea 2012 International journal of high-rise buildings Vol.1 No.1

Diagrid system has been in the spotlight for its superiority in terms of the resistance to lateral force when applied to skyscrapers. In diagrid system, most of columns can be eliminated because vertical loads (gravity loads) and horizontal loads (lateral loads) are delivered simultaneously thanks to the triangular shape of diagrid. However, lack of studies on connection shape and node connection details makes it hard to employ the system to the buildings. In this study, the structural safety of the node connections in circular steel tube diagrid system which has been considered in the Cyclone Tower in Korea (Seven stories below and fifty-one above the ground) was evaluated using the 4 full-scale specimens. The parameters are the extended length (20 mm, 40 mm & 60 mm), thickness (40 mm & 50 mm).

Evaluating high performance steel tube-framed diagrid for high-rise buildings

이동규,하태휴,정미영,김진호 국제구조공학회 2014 Steel and Composite Structures, An International J Vol.16 No.3

In recent, development of construction and design technology gives taller, larger and heavier steel framed structures. With the tendency of increasing high-rise building, this study is strongly related to structural system, one of significant components in structural design. This study presents an innovative structural system, with high performance steel material, diagrid. Its detail, structural analysis, and structural experiments are all included for the development of new structures.

Diagrid Systems for Structural Design of Complex-Shaped Tall Buildings

Moon, Kyoung Sun Council on Tall Building and Urban Habitat Korea 2016 International journal of high-rise buildings Vol.5 No.4

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.

연성능력향상을 위한 다이아그리드 시스템의 설계요소에 관한 해석적 연구

김기웅(Kim Kee-Woong),박성수(Park Sung-Soo) 대한건축학회 2011 大韓建築學會論文集 : 構造系 Vol.27 No.7

Purpose of this study is to supplement characteristic of brittle failure of diagrid system so as to look for ways to improvement seismic performance of diagrid system. Model for analysis was limited under H/500 in maximum displacement and they are 60-story diagrid system structures which comply with design code of KBC2009. Seismic performance of this model was evaluated by nonlinear static analysis and they consist of analysis model for shear lag and analysis model for ductility capacity. Considered variables are various members of diagrid, size of module, kind of composite structure, use of buckling restrained brace. Used lateral load resisting systems for composite structure are core system, rahmen system, bundle tube system, outrigger system. According to the analysis, shear lag effect is affected by diagrid member’s interval and wider interval reduces shear lag effect. In ductility capacity of the diagrid system, it is not effective to modify kind of composite structure or module size. Only using the Buckling Restrained Brace(BRB) has an effect on improving the ductility capacity. Among these models, pure diagrid system with buckling restrained braces, which didn’t use composite structure, showed the most effective ductility capacity for diagrid system.

초대형 대각가새 구조의 건물 높이에 따른 반응수정계수 평가

김경환(Kim Kyoung-Hwan),주영규(Ju Young-Kyu),김상대(Kim Sang-Dae) 대한건축학회 2009 大韓建築學會論文集 : 構造系 Vol.25 No.5

As number of the buildings increases, it shows new trends such as twisted, tilted, taperer shape. As a structural solution for the new trend buildings, diagonal grid (Diagrid) structural system was developed. Since the diagrid system is a new one, there is no reliable response modification factor in the codes available. Therefore, that of the braced frame is used for diagrid system. The purpose of this study is to evaluate the value of response modification factor for diagrid structural system. The parameters are the building heights from 4 stories to 36 stories and nonlinear static analyses was used to find the behaviour of the diagrid system. As a result, the response modification factor of the diagrid was proposed based on the pushover analysis.

Potentials of elastic seismic design of twisted high-rise steel diagrid frames

김선웅,이경구 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.18 No.1

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.

Seismic Performance of Wind-Designed Diagrid Tall Steel Buildings in Regions of Moderate Seismicity and Strong Wind

김선웅,이경구 국제구조공학회 2013 Steel and Composite Structures, An International J Vol.14 No.2

This study analytically evaluated the seismic performance of wind-designed diagrid tall steel buildings in regions of moderate/low seismicity and strong winds. To this end, diagrid tall steel buildings with varying wind exposure and slenderness ratio (building height-to-width ratio) conditions were designed to satisfy the wind serviceability criteria specified in the Korean Building Code and the National Building Code of Canada. A series of seismic analyses were then performed for earthquakes having 43- and 2475-year return periods utilizing the design guidelines of tall buildings. The analyses demonstrated the good seismic performance of these wind-designed diagrid tall steel buildings, which arises because significant overstrength of the diagrid system occurs in the wind design procedure. Also, analysis showed that the elastic seismic design process of diagrid tall steel buildings might be accepted based on some wind exposures and slenderness ratios.

MOGA-Based Structural Design Method for Diagrid Structural Control System Subjected to Wind and Earthquake Loads

김현수,강주원 한국강구조학회 2018 International Journal of Steel Structures Vol.18 No.5

An integrated optimal structural design method for a diagrid structure and control device was developed. A multi-objective genetic algorithm was used and a 60-story diagrid building structure was developed as an example structure. Artifi cial wind and earthquake loads were generated to assess the wind-induced and seismic responses. A smart tuned mass damper (TMD) was used as a structural control system and an MR (magnetorheological) damper was employed to develop a smart TMD (STMD). The multi-objective genetic algorithm used fi ve objectives including a reduction of the dynamic responses, additional stiff ness and damping, mass of STMD, capacity of the MR damper for the integrated optimization of a diagrid structure and a STMD. From the proposed method, integrated optimal designs for the diagrid structure and STMD were obtained. The numerical simulation also showed that the STMD provided good control performance for reducing the windinduced and seismic responses of a tall diagrid building structure.

반복하중을 받는 다이아그리드 노드에 관한 해석적 연구

배재훈(Bae Jae-Hoon),김영주(Kim Young-Ju),주영규(Ju Young-Kyu),김상대(Kim Sang-Dae) 대한건축학회 2009 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.29 No.1(구조계)

In the recent years, tall building is now being a trend not just the landmark of the only one country. As people‘s desire has been diversified recently, they start pursuing the architectually appealing structure and seeking for the building which has different elevation changes such as 3T(Twisted, Tapered, Tilted) buildings. Diagrid structural system enable them possible. These days, Diagrid structural system has been used not only for its distinctive appearance but also for the structural advantages. Although there have been heightened interest in diagrid structure, they have not been many studies about the diagrid structural system. there are some researches related to the diagrid nodes at that. therefore, In this study, in the course of preparing the cyclic loading test of the whole model of diagrid structure that has never tried before, the optimum node and the influence of the node shape (Pin & Rigid) to the structure will be suggested by nonlinear finite element analysis.

FEMA P695에 의한 다이아그리드 구조물의 내진성능평가

이용재,류재호,정인용,주영규 한국방재학회 2015 한국방재학회논문집 Vol.15 No.2

전 세계적으로 비정형 입면을 가진 초고층 건물에서 비정형 건물이 시공되고 있다. 비정형 초고층을 구현하기 위하여 다이아그리드 구조시스템이 사용되고 있다. 다이아그리드는 가새와 보 부재만으로 구성된 구조시스템이다. 따라서 기존의 구조시스템과는 다른 구조성능을 나타낸다. 많은 연구자들이 이러한 다이아그리드의 구조성능을 규명하기 위한 연구를 진행하고 있다. 본 논문에서는 다이아그리드 구조물의 내진성능에 관한 연구를 수행하였다. 연구의 진행은 다이아그리드 해석모델의 내진해석을 수행한 후 이를 FEMA P695 에서 제시하는 방법을 사용하여 구조물의 내진성능을 평가하는 방식으로 이루어졌다. FEMA P695 방법론은 붕괴여유비(Collapse Margin Ratio, CMR)를 통한 구조물의 내진성능을 평가하는 방법이다. rregular shaped tall building have been constructed around the world. Diagrid system has been used to represent the irregular shapes. Diagird system is consisted of only the brace and beam member. Therefore, diagrid system is shows a different structure performance than existing system. Many researchers have conducted a study to investigate the performance of the diagrid system. In this paper, seismic performance of diagrid structures was evaluated. First, the analysis model was designed. And analysis of diagrid model was evaluated by FEMA P695 method. FEMA P695 method is evaluate the seismic performance of diagrid structure through the CMR(Collapse Margin Ratio).