• Smart Structures and Systems
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• 제19권6호
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• pp.643-652
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• 2017

Pitched roof frames are widely used in construction of the industrial buildings, gyms, schools and colleges, fire stations, storages, hangars and many other low rise structures. The weight and shape of the gable frames with tapered members, as a familiar group of the pitched roof frames, are highly dependent on the properties of the member cross-sectional. In this work Enhanced Colliding Bodies Optimization (ECBO) is utilized for optimal design of three gable frames with tapered members. In order to optimize the frames, the design is performed using the AISC specifications for stress, displacement and stability constraints. The design constraints and weight of the gable frames are computed from the cross-section of members. These optimum weights are obtained using aforementioned optimization algorithms considering the cross-sections of the members and design constraints as optimization variables and constraints, respectively. A comparative study of the PSO and CBO with ECBO is also performed to illustrate the importance of the enhancement of the utilized optimization algorithm.

• 한국강구조학회 논문집
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• 제21권3호
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• pp.245-255
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• 2009

산업용 건축물은 일반적으로 박공지붕형 저층의 형태로 많이 건설된다. 본 연구는 박공지붕형 저층건물의 풍압분포와 특성을 알아보기 위하여 풍동실험을 수행하였다. 풍동실험은 경사각 변화에 따른 외장재용 피크외압계수 분포양상을 알아보기 위하여 동일한 폭과 높이, 길이를 가지지만 지붕 경사각이 서로 다른 7가지의 모형을 제작하여 실험하였다. 실험결과 지붕과 벽면의 모서리 부분에서 최대 피크외압계수가 나타났으며, 이를 KBC-2005 및 각국의 기준과 비교하여 보았다. 실험에 의한 피크외압계수는 AIJ-2004와 매우 유사하게 나타났지만 KBC -2005보다는 다소 크게 나타났다.

• 한국공간구조학회논문집
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• 제3권4호
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• pp.59-67
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• 2003

Genetic algorithm is one of the best ways to solve a discrete variable optimization problem. Genetic algorithm tends to thrive in an environment in which the search space is uneven and has many hills and valleys. In this study, genetic algorithm is used for solving the design problem of gable structure. The design problem of frame structure has some special features(complicate design space, many nonlinear constrants, integer design variables, termination conditions, special information for frame members, etc.), and these features must be considered in the formulation of optimization problem and the application of genetic algorithm. So, 'FRAME operator', a new genetic operator for solving the frame optimization problem effectively, is developed and applied to the design problem of gable structure. This example shows that the new opreator has the possibility to be an effective frame design operator and genetic algorithm is suitable for the frame optimization problem.

• 한국기계가공학회지
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• 제9권6호
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• pp.95-100
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• 2010

For orthodontic treatment, most commonly, an archwire is inserted into orthodontic brackets that can be made from stainless steel. Then, the archwires interact with the brackets to move teeth into the desired positions. However, the activation of an archwire may induce undesirable rotation of a tooth due to the moment application. An appropriate magnitude of the gable bends of an archwires prevents its rotation. However, it is not easy to predict the relationship between the rotation and the gable bend. This study presents the numerical approach to predict the rotation of a tooth with respect to the gable bend in the activation of an archwire. To predict the rotation of a tooth, the kriging interpolation method is introduced.

• Wind and Structures
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• 제4권2호
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• pp.119-130
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• 2001

The paper addresses the suitability of wind pressure coefficients specified in contemporary design standards and codes of practice for gable roofs of intermediate slope (roof angle $10^{\circ}-30^{\circ}$). In a recent research study, a series of low building models with different roof slopes in this intermediate range were tested in a boundary layer wind tunnel under simulated open country terrain conditions. This was different from the original study in the 70's, which produced the current provisions on the basis of a model tested only for a single roof slope (4:12) in this range. The results of the study suggest that a modification to the American wind provisions would be warranted to make them more representative of the true local and area-averaged wind loads imposed on gable roofs of intermediate slope.

• Wind and Structures
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• 제5권1호
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• pp.1-14
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• 2002

Artificial Neural Networks (ANN) have the capability to develop functional relationships between input-output patterns obtained from any source. Thus ANN can be conveniently used to develop a generalised relationship from limited and sometimes inconsistent data, and can therefore also be applied to tackle the data obtained from wind tunnel tests on building models with large number of variables. In this paper ANN model has been developed for predicting wind induced pressures in various zones of a Gable Building from limited test data. The procedure is also extended to a case wherein interference effects on a gable roof building by a similar building are studied. It is found that the Artificial Neural Network modelling is seen to predict successfully, the pressure coefficients for any roof slope that has not been covered by the experimental study. It is seen that ANN modelling can lead to a reduction of the wind tunnel testing effort for interference studies to almost half.

• Wind and Structures
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• 제7권6호
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• pp.359-372
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• 2004

Wind tunnel model studies were carried out to determine the wind load distribution on tributary areas near the gable-end of large, low-rise buildings with high pitch planar and curved roof shapes. Background pressure fluctuations on each tributary area are described by a series of uncorrelated modes given by the eigenvectors of the force covariance matrix. Analysis of eigenvalues shows that the dominant first mode contributes around 40% to the fluctuating pressures, and the eigenvector mode-shape generally follows the mean pressure distribution. The first mode contributes significantly to the fluctuating load effect, when its influence line is similar to the mode-shape. For such cases, the effective static pressure distribution closely follows the mean pressure distribution on the tributary area, and the quasi-static method would provide a good estimate of peak load effects.

• 건축사
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• 11호통권82호
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• pp.22-25
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• 1975

The aim of this study is the introduction of simplified method for the design stress analysis of multi-span gable frame structures with crane supports. Under the author's assumptions made previously for the same structures of single span, simplified stress analysis and exact computer analysis are excuted for some multi-span sample structures. Comparing the results of both stress analysis and with some modifications, a feasible simplified method for the design stress analysis of multi-span gable frame structures with crane supports is established.

• 한국주거학회논문집
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• 제20권3호
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• pp.19-26
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• 2009

The purpose of this study is to classify roof styles about high-rise apartment complexes in these days. Specially, it is focused on those in Daegu city. It has analyzed for 75 apartment complexes in Daegu city. Those complexes are all over 300 houses each and were built from 2004 to 2007. Generally, roof styles about high-rise apartment complexes are classed as a flat roof style and a slope-sided roof style. Types of the flat roof style were divided a flat roof style and a eyebrows roof style. And, types of the slope-sided roof style were divided a single slope-sided roof style, a gable roof style, and a hipped roof style. The curved roof style didn't show up at these cases. According to this study, the slope-sided roof style including the gable roof style was revealed the most common roof style about high-rise apartment complexes in Daegu city from 2004 to 2007. Among 76 cases of roof styles, the number of the gable roof style is 52, and the number of flat roof style is 18. Each roof style was changed for more decorative shape. Specially, in case of the flat roof style, 17 cases for 18 cases are built as a decorative flat roof style. and, 15 for 52 gable roof style cases are built as a decorative style, too. According this case study, we are able to know that the sort of roof style was advanced variously and decoratively, and the shape of roof style was combined more than 2 decorative factors. The roof style of high-rise apartment complex in future will be more various and decorative than this time and will be develop compositively.

• Wind and Structures
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• 제31권4호
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• pp.351-362
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• 2020

In this study, the impact of roof slope on the flow characteristics over low-sloped gable roofs was investigated using steady computational fluid dynamics (CFD) simulations based on a k-ω SST turbulence model. A measurement database of the flow field over a scaled model of 15° was created using particle image velocimetry (PIV). Sensitivity analyses for the grid resolutions and turbulence models were performed. Among the three common Reynolds-averaged Navier-Stokes equations (RANS) models, the k-ω SST model exhibited a better performance, followed by the RNG model and then the realizable k-ε model. Next, the flow properties over the differently sloped (0° to 25°) building models were determined. It was found that the effect of roof slope on the flow characteristics was identified by changing the position and size of the separation bubbles, 15° was found to be approximately the sensitive slope at which the distribution of the separation bubbles changed significantly. Additionally, it is suggested additional attention focused on the distributions of the negative pressure on the windward surfaces (especially 5° and 10° roofs) and the possible snow redistribution on the leeward surfaces.