• International Journal of High-Rise Buildings
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• v.8 no.4
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• pp.235-253
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• 2019

This paper reviews shape optimization studies for tall and super-tall building design. Firstly, shape effects on aerodynamic and response characteristics are introduced and discussed. Effects of various configurations such as corner modifications, taper, setback, openings, and twists are examined. Comprehensive comparative studies on various configurations including polygon building models, and composite type building models such as corner-cut and taper, corner-cut and taper and helical, and so on, are also discussed under the conditions of the same height and volume. Aerodynamic characteristics are improved by increasing the twist angle of helical buildings and increasing the number of sides of polygon buildings, but a twist angle of $180^{\circ}$ and a number of sides of 5 (pentagon) seem to be enough. The majority of examined configurations show better aerodynamic characteristics than straight-square. In particular, composite type buildings and helical polygon buildings show significant improvement. Next, shape effects on pedestrian-level wind characteristics around tall and super-tall buildings are introduced and discussed. Corner modification buildings show significant reductions in speed-up areas. On the other hand, setback and tapered models with wider projected widths near the ground show adverse effects on pedestrian-level wind characteristics.

• KIEAE Journal
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• v.16 no.3
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• pp.89-94
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• 2016

Purpose: This study aimed at developing an artificial neural network (ANN) model to predict the optimal start moment of the setback temperature during the normal occupied period of a building. Method: For achieving this objective, three major steps were conducted: the development of an initial ANN model, optimization of the initial model, and performance tests of the optimized model. The development and performance testing of the ANN model were conducted through numerical simulation methods using transient systems simulation (TRNSYS) and matrix laboratory (MATLAB) software. Result: The results analysis in the development and test processes revealed that the indoor temperature, outdoor temperature, and temperature difference from the setback temperature presented strong relationship with the optimal start moment of the setback temperature; thus, these variables were used as input neurons in the ANN model. The optimal values for the number of hidden layers, number of hidden neurons, learning rate, and moment were found to be 4, 9, 0.6, and 0.9, respectively, and these values were applied to the optimized ANN model. The optimized model proved its prediction accuracy with the very storing statistical correlation between the predicted values from the ANN model and the simulated values in the TRNSYS model. Thus, the optimized model showed its potential to be applied in the control algorithm.

• Earthquakes and Structures
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• v.10 no.5
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• pp.1049-1066
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• 2016

An approximate analysis is presented for multi-story setback buildings subjected to ground motions. Setback buildings with mass and stiffness discontinuities are common in modern architecture and quite often they are asymmetric in plan. The proposed analysis provides basic dynamic data (frequencies and peak values of base resultant forces) and furthermore an overview of the building response during a ground excitation. The method is based on the concept of the equivalent single story system, which has been introduced by the author in earlier papers for assessing the response of uniform in height buildings. As basic quantities of the dynamic response of elastic setback buildings can be derived by analyzing simple systems, a structural layout of minimum elastic rotational response can be easily constructed. The behavior of such structural configurations, which is basically translational into the elastic phase, is also examined into the post elastic phase when the strength assignment of the various bents is based on a planar static analysis under a set of lateral forces simulating an equivalent 'seismic loading'. It is demonstrated that the almost concurrent yielding of all resisting elements preserves the translational response, attained at the end of the elastic phase, to the post elastic one.

• International Journal of High-Rise Buildings
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• v.8 no.4
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• pp.303-311
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• 2019

The effectiveness of aerodynamic modification to reduce wind loadings has been widely reported. However, most of previous studies have been investigated dynamic forces and pressure distributions on tall buildings with various unconventional configurations. This study was investigated dynamic characteristics and aerodynamic instability of super-tall buildings with unconventional configurations through extensive aeroelastic model experiments. Seventeen types of supertall building models were considered such as basic and corner modification with corner cut, chamfered, oblique opening, tapered, inversely tapered, bulged, helical with twist angles of $90^{\circ}$, $180^{\circ}$, $270^{\circ}$, $360^{\circ}$ and composite with $360^{\circ}$ helical & corner cut, 4-tapered & $360^{\circ}$ helical & corner cut, setback & corner cut, setback & $45^{\circ}$ rotate. As a result, aerodynamic characteristics of helical models with single modification are superior to those of other models with single modification. However, effect of twist angle for helical model is negligible. Further, the 4-tapered & $360^{\circ}$helical & corner cut model is most effective in reducing the along- and across-wind fluctuating displacement responses in all of experimental models.

• International Journal of High-Rise Buildings
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• v.4 no.3
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• pp.199-207
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• 2015

Abeno Harukas is the tallest building in Japan and is located in Abeno, which is one of the three main railway transport nodes in Osaka. This building has a height of 300 meters, and its lowest levels are 30 meters below ground. It contains a department store, museum, offices, a hotel, and an observatory. In this urban renewal project, a section of the department store that encloses the station was dismantled and replaced by a supertall building complex, while infrastructure was simultaneously constructed, including: upgrades to the station and the existing department store, improved connections to the subway and pedestrian bridges, and a new pedestrian walkway over the road. In this paper, the ingenious erection processes, newly developed technologies, and precise construction management techniques are introduced for Japan's tallest building.

• International Journal of High-Rise Buildings
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• v.2 no.3
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• pp.213-228
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• 2013

Tall buildings have been traditionally designed to be symmetric rectangular, triangular or circular in plan, in order to avoid excessive seismic-induced torsional vibrations due to eccentricity, especially in seismic-prone regions like Japan. However, recent tall building design has been released from the spell of compulsory symmetric shape design, and free-style design is increasing. This is mainly due to architects' and structural designers' challenging demands for novel and unconventional expressions. Another important aspect is that rather complicated sectional shapes are basically good with regard to aerodynamic properties for crosswind excitations, which are a key issue in tall-building wind-resistant design. A series of wind tunnel experiments and numerical simulation have been carried out to determine aerodynamic forces and wind pressures acting on tall building models with various configurations: corner cut, setbacks, helical and so on. Dynamic wind-induced response analyses of these models have also been conducted. The results of these experiments have led to comprehensive understanding of the aerodynamic characteristics of tall buildings with various configurations.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.12-13
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• 2020

Construction projects and buildings are becoming taller and larger, and the size of water tanks of production facilities and high-rise buildings is also gradually increasing. Most large water tanks apply a waterproofing layer to the water tank type concrete structure. The application of polyurea coating materials, which are excellent in water resistance, chemical resistance, physical performance, rapid hardening, and workability is gradually increasing as waterproofing and anticorrosion layer for water tank. As a result, defects such as water leakage and damage to the waterproofing layer are continuously occurring, causing production disruption, setback to users. Therefore, it is required to review suitability through performance verification of the waterproofing and anticorrosion system.

• Journal of KIBIM
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• v.7 no.1
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• pp.9-17
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• 2017

This study aims at finding issues and ideas of waterfront planning through analysing planning concepts and characteristics of New York City Waterfront Comprehensive Plan(NYC WCP). The first NYC WCP in 1992 divided waterfront area as 4 functional areas which are natural, public, working and redeveloping waterfront. The characteristics of WCP in 1992 are zonning, height, setback, public access, visual corridor, floor area and so forth. After then NYC WCP revision in 2011 intergrated and developed the former plan through the eight visions which are expanding public access, enlivening the waterfront, improving water quality, restoring the natural waterfront, enhancing the Blue Network, improving government oversight and increasing climate resillience. In conclusion, NYC WCP successfully achieved both sufficient capacity of planning concepts and design guidelines for each region.

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.1
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• pp.45-54
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• 2011

The results of examining the architectural features and changes of the main building of Dogapsa temple which is multi roofs wooden structure are as follows. The passage comparing 'Dogapsa' of <>, account of Lee Ha Gon's trip as the literature showing the appearance of Dogapsa temple in the early 18th century to Borimsa through verse of 'Dutacho' was noticeable. Dogapsa temple at Yeongam was distant over 100 ri from Borimsa temple at Jangheung and it was considered that there were many temples at Mt. Wolchul, Yeongam and there were also many temples to be comparable with it. But, Dogapsa temple was compared to Borimsa temple because verses 'many-storied building is high and immense' of 'Dogapsa' at <> and 'Dogapsa is lower than Borimsa at Jangheung' at 'Dutacho' of <> were interpreted as the existence of multi roofs Buddhist temple which had something in common with Dogapsa and Borimsa and was comparable to them. According to existing materials, it was assumed that the main building of Dogapsa was burnt through the Japanese invasion of Korea in the 52nd year of the sexagenary cycle (Eulmyooebyeon, 1555) and Jungyujaeran (1597), but record of major history of the main buildings of Dogapsa and Borimsa indicated that multi roofs wooden structure of the two temples were built at the same period. Since multi roofs wooden structure of main building of Borimsa was rebuilt in 1692, these buildings existed from the early 18th century to middle 18th century.

• Convergence Security Journal
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• v.16 no.3_1
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• pp.57-67
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• 2016

This article reviewed the status of military force on the DMZ(demilitarized zone) without any confidential problems after literature reviewing on a ceasefire agreement and these powerful military force is judged to be a very serious setback to peaceful reunification of the Korean Peninsula. Also it suggests the ways to reduce inter-korean military force based on the political and economic phenomenon to preparing for an era of reunification of the Korean Peninsula. The easing of tension on the inter-korean military force is an essential element in building infrastructure of peaceful reunification. From now on, both Seoul and Pyongyang might check inter-Korea exchange cooperation Project and reconcile their differences. Primarily, The troops of DMZ would be minimized by Modernization for Military confidence-building. Increasing North-South hotline as possible further, it could contributes to ease of tension in case of emergency. Political and economic plans should be presented that do not arise the military tension simultaneously with ensuring political and economic aspects in the North Korea's regime.