• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.199-203
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• 2016

This study relates to the development of a program for calculating the roofed pechan prism design data. First, we set the roofed pechan prism design variables and derive the relational expressions between them. With this expressions, we could develope the program that outputs the numerical data for roofed pechan prism design when the face-length and the effective incident beam diameter are given. In fact, applying this program to the prism which is not the commercial size, we were able to calculate the design data very quickly, so that we can easily acquire the 3D structure of the actual roofed pechan prism. This means that we can quickly ensure the structural data of roofed pechan prism which is required for the product development and we are able to develop the new products related to the scope at a faster speed.

• Journal of the Korean Institute of Gas
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• v.9 no.4 s.29
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• pp.36-43
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• 2005

In this paper, the optimized design of a roof structure f3r a LNG outer tank has been analyzed using the Taguchi design method. This method may efficiently optimize the design parameters of a LNG roof structure in terms of H beam and L beam structures, and a thickness of a concrete structure. The FEM computed results indicate that the thickness of a concrete structure is a dominant factor of a roof structure design. The H and L beam structures do not affect a maximum stress and deformation of a reinfarced roof structure. This means that H and L beam structures only support a dead weight of a concrete roof during a consolidation of a reinforced concrete. Based on the computed results by the Taguchi design method, the number of beams and thickness of a reinforced concrete are given as H=30, L=7, and t=1.2m.

• Journal of Korean Society of Steel Construction
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• v.21 no.3
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• pp.245-255
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• 2009

The low-rise buildings with gable roofs are commonly used in a number of industries. In order to study the characteristics of peak external pressure coefficient on low-rise buildings with gable roofs, wind-tunnel test have been carried out. Wind-induced pressures were measured simultaneously at many points on wind-pressure models, typical of simple low-rise buildings with gable roofs, which have seven different roof slope with constant width(D), height(H), and length(D). The pressure measurements were made in one kind of turbulent boundary layer, which simulated the natural winds over typical suburban terrains at a geometric scale of 1/150. The results indicate that peak external pressure coefficient on the roof and wall edges were increased. The results compared with wind standard of KBC-2005 and standards of various nations. The comparative resultant, experimental result appeared very similar at AIJ-2004. But the results were somewhat larger then wind standard of KBC-2005.

• Land and Housing Review
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• v.13 no.4
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• pp.115-123
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• 2022

This study aims to introduce a temperature discoloration roof system and its cooling effect in the summer. Temperature discoloration paints can reverse their colors based on temperature changes. If these paints on the roof surface could color-shift between white in the summer and black in the winter, the indoor cooling and heating loads can be affected by the changes in reflection and absorption of solar radiation. Focusing on the summer period, the study analyzed the cooling effect of applying temperature discoloration paint that color-shifts from white to black on the roof surface of a small experimental building module and compared it to commonly used gray and green roof colors. Results of the experiment showed that the surface temperature of the roof with temperature discoloration paint was lower than the gray and green color roofs by a maximum of 10℃. Furthermore, the indoor temperature of the experimental module with the temperature discoloration roof was lower than the gray and green roofs by approximately 3℃. Findings of the study indicate that the application of temperature discoloration paint to the roof can reduce indoor cooling loads.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.725-730
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• 2017

The strength ratio of the main structures of buildings gradually increasing, due to the advances made in analysis and cost saving techniques. In this study, to examine the stability of industry buildings using sandwich panels as roof assemblies, we examine the changes in the moment strength ratio of the main structures caused by increasing the roof load. This study adopts the PEB structure and three H-steel structure as the structural analysis models. In the case where the additional load exceeds about 11% of the roof design load, the strength ratio exceeds 1 for the main structure. In the case where the additional load exceeds about 36%(of the roof design load), the working moment exceeds the plastic moments, which leads to major damage to the structure. This study compares 1) the maximum load according to the purlin spaces, 2) the maximum load by KS, and 3) the maximum load calculated from the test results of the manufacturer.The maximum bearing load of the panels determined by all three methods exceeds the structure failure threshold load of the main structure. This study provides evidence that an unexpected increase in the roof load might cause the whole structure to collapse, due to the failure of the main structural members, before the failure of the roof assemblies. Therefore, information on the structural performance of the sandwich panels is required for the structural design, and the sandwich panels should be considered to be an integral part of the overall structural design.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.4
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• pp.327-336
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• 2007

The 3D building modeling is one of crucial components in building 3D geospatial information. The existing methods for 3D building modeling depend mainly on manual photogrammetric processes by stereoplotter compiler, which indeed take great amount of time and efforts. In addition, some automatic methods that were proposed in research papers and experimental trials have limitations of describing the details of buildings with lack of geometric accuracy. It is essential in automatic fashion that the boundary and shape of buildings should be drawn effortlessly by a sophisticated algorithm. In recent years, airborne LiDAR data representing earth surface in 3D has been utilized in many different fields. However, it is still in technical difficulties for clean and correct boundary extraction without human intervention. The usage of airborne LiDAR data will be much feasible to reconstruct the roof tops of buildings whose boundary lines could be taken out from existing digital maps. The paper proposed a method to reconstruct the roof tops of buildings using airborne LiDAR data with building boundary lines from digital map. The primary process is to perform octree-based segmentation to airborne LiDAR data recursively in 3D space till there are no more airborne LiDAR points to be segmented. Once the octree-based segmentation has been completed, each segmented patch is thereafter merged based on geometric spatial characteristics. The experimental results showed that the proposed method were capable of extracting various building roof components such as plane, gable, polyhedric and curved surface.

• Korean Journal of Construction Engineering and Management
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• v.12 no.6
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• pp.151-159
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• 2011

Due to the Korean government's renewable energy support policy such as the renewable energy utilization building certificate and enlarging the compulsory ratio of investment on the public building, the rooftop photovoltaic projects are expanding rapidly. It is very important for the rooftop photovoltaic projects to analyze the shading effect of the adjacent structures or own facilities. But, the photovoltaic arrangements are planned by the experience of the designers or simple graphic tools. The purpose of this study is to build the process model for optimizing of rooftop photovoltaic arrangement based on three-dimensional geo-spatial information.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.228-231
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• 2001

Construction of roof structure, cable suspended structure, for Pusan main stadium is adapted a lifting method that is VSL lifting system. 5 precesses are practiced for erection of the roof structure including the first lifting process for erection of upper cables and the second lifting process for erection of lower cables. Since all cables of this roof structure with two open speller sockets are determined their length, some cable were wrong length, the roof structure would be unstable. But At complete of erection for the roof structure each cab3e is attained to theoretical tension force with average $4\%$ errors.

• Journal of Korean Association for Spatial Structures
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• v.10 no.1
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• pp.85-93
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• 2010

This paper suggests a vibration control method long span structures with trussed roof. Basic concept of this method is based on the energy absorption through hysteresis loop of an elasto-plastic element. This element is attached on the top of the column supporting the roof. Two different types of roofs and three of earthquake waves are used in the investigation. It shows that this is very efficient method to reduce the seismic energy of roof member transferred from the column.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.4
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• pp.377-386
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• 2003

The proposed simplified MDOF model is applied to a half-scale single-story reinforced masonry test building with a single diagonally-sheathed diaphragm. Comparisons of analytical studies to experimental tests can be valuable for understanding the seismic response of these types of buildings and for determining the qualities and limitations of the simplified models. A model calibration process is performed in this paper to determine the required structural properties based on the elastic and inelastic test responses for test building. This approach is necessary since established methods to determine the in-plane and out-of-plane stiffness, strength, and hysteresis do not exist.