• Structural Engineering and Mechanics
• /
• v.21 no.4
• /
• pp.375-392
• /
• 2005

Cable supported structures offer an elegant and economical solution for bridging over long spans with resultant low material content and ease of construction. In this paper, a model of shallow cable supported footbridge with reverse profiled pre-tensioned cables is treated and its load deformation characteristics under different quasi-static loads are investigated. Effects of important parameters such as cable sag and pre-tension are also studied. Numerical results performed on a 3D model show that structural stiffness of this bridge (model) depends not only on the cable sag and cross sectional areas of the cables, but also on the pre-tension in the reverse profiled cables. The tension in the top supporting cables can be adjusted to a high level by the pre-tension in the reverse profiled bottom cables, with the total horizontal force in the bridge structure remaining reasonably constant. It is also evident that pre-tensioned horizontally profiled cables can greatly increase the lateral horizontal stiffness and suppress the lateral horizontal deflection induced by eccentric vertical loads.

• Proceedings of the KSR Conference
• /
• 1998.05a
• /
• pp.466-473
• /
• 1998

LRV(Light Rail Vehicle) is one of the most useful way for urban transit. HDPIC has designed and manufactured the LRV train set for Manila Line 1 expansion. The LRV is composed of two carbody sections which are coupled by a articulated bogie. The articulated bogie and two motorized bogies have slewing rings in order to improve the curving performance and ride quality. Carbody structures are mainly made of low-carbon stainless steel (STS301L), and the carbody bolsters and draft sills are made of rolled steel for welded structures. The authority's specifications specified the design load conditions and weight limits. Design load conditions are vertical load, compressive load and diagonal jacking, and the maximum axle load is 10.7 ton. In order to meet those requirements, the stiffness and strength of carbody structure were predicted using finite element analysis during design stage. The half or full structure is modeled and analyzed with design load conditions, and critical areas are analysed in detail using sub-modeling method. The strength and strength of carbody structure was also verified by the load test. The analysis and test results show a good agreement.

• Korean Institute of Interior Design Journal
• /
• v.22 no.4
• /
• pp.23-32
• /
• 2013

This study represents something in common and differences of organic characteristics between early modern architecture and contemporary architecture analysing F. L. Wright's Robie House and Toyo Ito's Sendai Mediatheque. A natural organic body cannot be separated from the natural environment, and each part of an architecture has each own property and forms a whole at the same time. That is a basic concept of organic architecture, and a framework for analysis is set up based on it. The followings are similarities and differences of organic concept and interpretation between Wright's Robie House and Ito's Sendai Mediatheque First, Wright' Robie house unites with the natural surrounding, using a physically close connection to the ground. In contract, Ito's Mediatheque shows characteristics of noncentural and fluidic space that are metaphorically reflecting tangible and intangible of factors in modern city, where there is an ambiguous physical boundary between architecture and urban environment. Next, floors, walls and ceilings of Wright's housing as for basic building blocks are physically separated and at the same time form formative unity from the point of view of a physical and structural organic body. And continuous flow of faces of separated walls form an organism united with the nature from a physical aspect. On the contrary to this, there is an no-boudary and floating organic architecture of integrated structure from ambiguous setting of relation between architecture and urban space in Ito's architecture. Especially, Mediatheque shows semantic integration of floating urban environmental factors through horizontal and vertical integration of horizontal slabs, vertical pipes, and skins. Last, horizontal and vertical factors of Wright' Housing is appreciated as an basic experienced structure in terms of spacial perception and fluidic inner spaces in Wright's housing is completed with a series of spatial experiences in a visual sense. On the other hand, no-boundary and floating space of Ito's architecture accept user's physical and virtual body. Especially, there is an integration transcending beyond time and space, accepting an imaginary body and events with the course of time at Ito's Mediatheque.

• Korean Institute of Interior Design Journal
• /
• v.19 no.2
• /
• pp.107-116
• /
• 2010

In Europe, traditionally the low-rised buildings for public art museum have been constructed since the 18th century like any other buildings and these are because of the technical issue for construction difficulty. Even if the low-rised art museum buildings are still continued for it's construction, gradually the high-rised art museum buildings begin to be build due to the development of contemporary technology in high-dense modern urban space. This tendency of high-rised art museum building in recent years is expected to affect on the interior space of it and most of all the spatial change in conjunction with circulation system variation is remarkable. Because the circulation system in art museum means tourist's spatial experience and it normally controls the experience of knowledge in art museum. This study is to understand how the multi-floored art museums in Europe affect to the spatial structure and how this is related to the circulation system. And also the study raised an issue on what it's social meaning is. Through these analysis the study can provide the meaning of multi-floored art museum and basic indication in art museum planning. To understand this, the study calculated the number of stories, number of vertical circulation and number of ring-structure space. Also the study tired to use space syntax tools, which are connectivity, integration value, integration value in major space, integration value in vertical circulation and intelligibility value. those tools alculated topological transfiguration of the whole space.Throughout the study, it was concluded that the influence of high-rised art museum in Europe changed the spatial structure and circulation system. The topological center of art museum that has been the grand space since 18th century changed to the vertical circulation due to the it's roll of distributing visitors to each floor. It became a starting point of spatial deployment and experience in art museum.

• Journal of Forest and Environmental Science
• /
• v.28 no.1
• /
• pp.56-62
• /
• 2012

There is little information about appropriate greenspace structures to satisfy aesthetic function in Korea. The purpose of this study was to analyze Korean's aesthetic preferences for greenspace structures concerned with urban tree plantings of an areal type to explore desirable greenspace landscapes. The study considered 5 structural variables of greenspace which were species composition, tree density, tree size, vertical and horizontal structure, and tree layout pattern. A photo-questionnaire was prepared through color simulations of different landscape types for each structural variable. Preference responses of an interval-scale rating from 214 respondents were statistically analyzed between landscape types and between respondent groups. Respondents preferred greenspace landscapes with diverse tree species to single species, higher tree density to lower density, larger trees to many smaller trees, multilayered and grouped plantings to single-layered and sparse plantings, and informal pattern to formal pattern. These preferences tended to be relatively higher for educated specialist and student groups than for other generalist group. Thus, multilayered and dense plantings in natural pattern including larger trees of diverse species, which are similar to ecological plantings, are recommended to increase aesthetic function of greenspace.

• International Journal of High-Rise Buildings
• /
• v.3 no.4
• /
• pp.297-304
• /
• 2014

Recently, there have been some reported examples of structural collapse due to gravity, subsequent to damage from accident or an excitation that was not prepared for in the design process. A close view of new concepts, such as a redundancy and key elements, has been taken with the aim of ensuring the robustness of a structure, even in the event of an unexpected disturbance. The author previously proposed a sensitivity index of the vertical load carrying capacity to member disappearance for framed structures. The index is defined as the ratio of the load carrying capacity after a member or a set of an adjacent member disappears, to the original load carrying capacity. The member with the highest index may be regarded as a key element. The concept of bio-mimicry is being applied to various fields of engineering, and tree-shaped structures are sometimes used for the design of building structures. In this study a sensitivity analysis is applied to the irregular-framed structures such as tree-shaped structures.

• Structural Engineering and Mechanics
• /
• v.88 no.3
• /
• pp.263-271
• /
• 2023

Base isolation is a widely used technique for the seismic control of structures as it reduces the structural seismic demand. However, displacement of the isolation layer is not economically feasible in congested urban areas. To resolve the issue, an innovative system is proposed here to isolate both horizontally at the base and vertically in the upper portion of the structure. A simplified linear three degree-of-freedom (3DOF) model of the system that considers the mass and stiffness ratios of the substructure has been introduced and analyzed in MATLAB by spectrum analysis. The 3DOF model results revealed that, when the period of the soft substructure reaches 2.5 times that of the stiff substructure, the isolation and the lower substructure responses decrease by 65% and 51%, respectively. Time-history analysis of a MDOF system at three frequency ratios under a wide range of ground motions indicated that, at the expense of accepting a certain large drift by the soft substructure in the upper portion of the structure, base isolation displacement can be decreased by 10%.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.374-377
• /
• 2005

Automobile is in charge of most transportation system in modern urban city. However, in fact, cause of problem of road state, environment, and the other reasons, urban transit system is using as Mass Transit nowadays. Nevertheless Urban transit system is considering many kind of safety fact of that system which is increasing continuously nowadays, it occurs various train accident. This paper describes 3D Dimensional Measurement(EDM testing) and tensile testing results of carbody structure for crashed EMU(Electric Multiple Units). Tensile tests were performed on two different types of specimens in order to evaluate the strength changes before and after damages, obtained from plastic deformed area and nondeformed region of the crashed EMU. And Structural analysis of EMU was performed for the criteria of safety assessment. Structural analysis using commercial I-DEAS software provided important information on the stress distribution and load transfer mechanisms as well as the amount of damages during rolling stock crash. The testing results have been used to provide the critical information for the criteria of safety diagnosis.

• Journal of Environmental Impact Assessment
• /
• v.31 no.4
• /
• pp.241-249
• /
• 2022

Humans and wild birds coexist in cities, where habitat fragmentation due to urbanization threatens the habitat and movement of birds. In this study, in order to identify landscape features associated with wild bird collide, we characterized landscape composition within a 500 m radius and points of wild bird carcasses in Suwon-city, South Korea. Dead birds were identified as having a Normalized Difference Vegetation Index (NDVI) of 0.3, Normalized Difference Built-up Index (NDBI) of -0.05, and Normalized Difference Water Index (NDWI) of -0.16 at the points of collide. And there were NDVI of 0.34, NDBI of -0.01, NDWI of -0.18, building height of 13.8 m, and soundproof wall length of 227.3 m within a radius of 500 m. Land cover type was dominated by grassland, used area, and bare land. In particular, the edges of urbanized areas, where apartments bordered forests, reservoirs, and golf courses, were identified as high-risk spaces. In order to minimize bird mortality risk in urban environments, the impact of changes to a vertical landscape should be reviewed from an environmental impact assessment approach. In addition, a preventive management plan that considers the temporal and spatial features that wild animals can safely avoid and adapt to in urbanized spaces should be prepared.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.11 no.2
• /
• pp.199-211
• /
• 2009

Development of underground space is actively performed globally for better life in the surface, and the scale of the space is increasing. Extreme care should be taken in the construction of the underground space in urban areas in order to avoid damage of adjacent structures and interference with existing underground space. In case of shallow tunnels, reinforcement of ground and structures is necessary to minimize the damage to structures due to excavation but any standard for optimum range of the reinforcement has not been established yet. In this paper, a series of numerical analyses have been performed for a 20 m diameter tunnel excavated underneath a structure to investigate the degree of damage of the structure according to vertical and horizontal spacing between the tunnel and structure. In addition to that, optimum range of reinforcement is presented for each case where reinforcement is required. It has been observed that the reinforcement is necessary for the ground condition adapted in the analyses as follows: (1) if horizontal spacing ($S_{H}$) approaches to 0D (D: equivalent diameter of tunnel) for vertical spacing (Sv) of 0.5D, and (2) if tunnel exists underneath the structure for vertical spacing (Sv) of 0.75D. The reinforcement is not necessary for Sv of 10 regardless of $S_{H}$. It also has been obtained that the optimum ranges of the reinforcement around structure foundation are 7 m in depth and whole width of the structure and 5 m beyond tunnel sidewall. These reinforcememt ranges have been confirmed to be enough for stability of the structure if types of reinforcement method is appropriately selected.