• International Journal of Highway Engineering
• /
• 제12권2호
• /
• pp.71-79
• /
• 2010

The influence of fines of the frost susceptibility of subgrade soils were established by laboratory freezing system test simulating closely the thermal conditions in the field. During the winter season, the climate is heavily influenced by the cold and dry continental high pressure. Because of siberian air mass, the temperature of January is $-6{\sim}-7^{\circ}C$ on average. This chilly weather generate the frost heaving by freezing the moisture of soil and damage potential of the road structure. In the freezing soil, the ice lenses increase the freeze portion of soil by absorbing the ground water with capillary action. However, the capillary characteristics differ from the sort of soil on the state of freezing condition. In the current design codes for anti-freezing layer, the thickness of anti freezing layer is calculated by freezing depth against the temperature condition. Therefore, they have a tendency of over-design and uniform thickness without the considerations of thermal stability, bearing capacity and frost susceptibility of materials. So, it is essential for studying the appropriateness and bearing capacity besides the seasonal and mechanical properties of pavement materials to take a appropriate and reasonable design of the road structure. In this Paper, the evaluation of frost susceptibility was conducted by means of the mechanical property test and laboratory freezing system apparatus. The temperature, heaving amount, heaving pressure and unfrozen water contents of soil samples, the subgrade soils of highway construction site, were measured to determine the frost susceptibility.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• 제11권5호
• /
• pp.1791-1798
• /
• 2010

This research predicted the change and characteristics of space structure by new residential area development through objective and quantitative analysis of urban spatial configuration using space syntax and associated the prediction with the city status statistics data and quantitative analysis, and the results are summarized as follows: (1) If large scale new residential area of Dongnae township proceeds to be developed according to present plan, accessibility to the new residential area will drop, and also as the outside space ripple effects by new residential area development also are anticipated small, the new residential area apprehensibly will not succeed to play the role of integrating the entire city structurally, but will cause structural problem, severing the city structure. (2) If the city planned road between existing urban center planned based on 2004 Chuncheon city plan overall drawing and main road which is the entrance road of the planned new residential area is developed together, the accessibility to the entire space of Chuncheon city and the new residential area will be easy, allowing the new residential area properly integrated into the entire space of Chuncheon city, consequently giving a prediction that classification of land use between the central part of Chuncheon city and surrounding residential area would become conspicuous.

• Structural Monitoring and Maintenance
• /
• 제9권4호
• /
• pp.323-336
• /
• 2022

Steel truss bridge is one of the most widely used bridge types in Indonesia. Out of all Indonesia's national roads, the number of steel truss bridges reaches 12% of the total 17,160 bridges. The application of steel truss bridges is relatively high considering this type of bridge provides advantages in the standardization of design and fabrication of structural elements for typical bridge spans, as well as ease of mobilization. Directorate of Road and Bridge Engineering, Ministry of Works and Housing, has issued a standard design for steel truss bridges commonly used in Indonesia, which is designed against the design load in SNI 1725-2016 Bridge Loading Standards. Along with the development of actual traffic load measurement technology using Bridge Weigh-in-Motion (B-WIM), traffic loading data can be utilized to evaluate the reliability of standard bridges, such as standard steel truss bridges which are commonly used in Indonesia. The result of the B-WIM measurement on the Central Java Pantura National Road, Batang - Kendal undertaken in 2018, which supports the heaviest load and traffic conditions on the national road, is used in this study. In this study, simulation of a sequences of traffic was carried out based on B-WIM data as a moving load on the Australian type Steel Truss Bridge (i.e., Rangka Baja Australia -RBA) structure model with 60 m class A span. The reliability evaluation was then carried out by calculating the reliability index or the probability of structural failure. Based on the analysis conducted in this study, it was found that the reliability index of the 60 m class Aspan for RBA bridge is 3.04 or the probability of structural failure is 1.18 × 10^-3, which describes the level of reliability of the RBA bridge structure due to the loads from B-WIM measurement in Indonesia. For this RBA Bridge 60 m span class A, it was found that the calibrated nominal live load that met the target reliability is increased by 13% than stated in the code, so the uniform distributed load will be 7.60 kN/m² and the axle line equivalent load will be 55.15 kN/m.

• Composites Research
• /
• 제21권6호
• /
• pp.8-14
• /
• 2008

Lighting system of road is an essential structure used for the safety of pedestrians and vehicles. Most of the lighting pole is made with steel which is vulnerable under corrosive environment. To overcome such corrosion problems, stainless steel and iron steel are used, but they are usually manufactured by hand which is not efficient. Due to their high strength and stiffness, when there is car collision with the lighting pole structure the safety of driver may not be ensured. Hence, the development of new-type lighting pole system which is easy to adjust the right on the road, lengthen the service life, and reduce the maintenance, is necessary. Lighting pole made with aluminum alloy is high in strength per unit weight, is strong against corrosive environment, and is easy to construct due to flexibility and right weight. But, because the strength and stiffness of the material is lower than that of steel, the structural safety and serviceability of the system can be a problem. To mitigate the structural problem associated with conventional lighting pole system, experimental investigation is conducted on the conventional lighting pole and rib reinforced aluminum alloy lighting pole, respectively. By comparison of results, it was found that the rib reinforced Mg-Si aluminum alloy lighting pole is efficiently applicable to the lighting pole system of road.

• Journal of architectural history
• /
• 제22권2호
• /
• pp.43-54
• /
• 2013

Compared to Early Chosun Dynasty, the spatial structure of most local Eupseongs of Korea had a standardized change with the expansion and spread of the Rye-hak(禮學:a study of confucius Rite). Meanwhile in the process of rebuilding Eupseongs there was a tendency of relocation of the local government offices(官衙) and its attached facilities in terms of functions and use. Although it was PyeongSanseong Miryang Eupseong had an unreasonable spatial structure locating Gaeksa(客舍; accommodation house for visitors) in the middle of the local government office complex, and Dongheon(東軒;main office building) in the east of it before the Japanese Invasion of Korea in 1592. However with the reorganization of spatial Structure of local Eupseongs after the Japanese invasion Gaeksa was moved to the foot of Adongsan where commanded a fine view of river. Dongheon was moved to the center of Eupseong for the effective management of its auxiliary organizations. It was because road system and administrative efficiency had a serious effect on deciding the location of the local government office and its attached facilities. After the Japanese invasion Hyangchoeng(鄕廳), having been out of Eupseong, also was moved to the independent location within Eupseong separate from Dongheon and Gaeksa. It seemed to take into account the autonomy of Hyangchoeng. Dongheon, Gaeksa, and Hyangchoeng which are the crucial facilities of Milyang Eupseong were arranged at each angular point of big triangle. In order to enhance the administative efficiency, the attached administrative facilities were arranged surrounding Dongheon and Hyangchoeng. The spatial structure of Milyang Eupseong in the late Choseon dynasty was of great difference from that of uniformly organized system of early Choseon Period. It was because the development of administrative function, the pursuit of efficiency, and commercial progress had a great impact on the change of urban space.

• International Journal of Highway Engineering
• /
• 제17권1호
• /
• pp.59-67
• /
• 2015

PURPOSES : In this study, an image analysis method is used to evaluate the pore structure characteristics and permeability of hybrid concrete. METHODS : The binder weight of hybrid concrete is set to $400kg/m^3$, $370kg/m^3$, and $350kg/m^3$, and for each value of binder weight, the pore structure and permeability of concrete mixture is evaluated. The permeability of hybrid concrete is evaluated using a rapid chloride penetration test(RCPT). RESULTS : The concrete pore structure characteristics of hybrid concrete reveals that as the binder weight is reduced, the entrained air is reduced and the entrapped air is increased. The permeability of the hybrid concrete for all values was measured to be below 1000 C, which indicates a "Very Low" level of permeability relative to the evaluation standard of KS F 2711. Additionally, as the binder weight is decreased, there is a significant increase in the permeability of chloride ions. CONCLUSIONS : In this study, the pore structure characteristics of hybrid concrete at different binder weights shows that as the binder weight is reduced, the entrained air is reduced and the entrapped air is increased. Consequently, chloride ion penetration resistance of the hybrid concrete is diminished. As a result, it is expected that this will reduce the concrete's durability.

• Journal of the Korean Institute of Rural Architecture
• /
• 제15권3호
• /
• pp.17-24
• /
• 2013

This study examined and investigated architectural characteristics such as the use of buildings, the number of layers, and structure, and roof landscape characteristics such as roof types, materials, and color in rural villages which were located on the street on the assumption that the landscape of rural villages should be managed by considering visual aspects. The results were as follows. The commonest frequency was found in 'residence'(2/3) for the use of buildings and 'masonry structure'(2/3) for the structure. 'Wood structure' and 'light gauge steel structure(prefabricated structure)' were also commonly found. The results suggest that although many rural houses have partially improved by agricultural and fishery development projects and garden suburbs has been increased by city residents' desire for rural life, there have been still many old houses. Frequently used roof types were a gambrel roof and a hipped roof. Roof materials were mixed in several materials such as tiles, slate, panels, color steel plate, reinforced concrete, and asphalt shingles. Roof color was also mixed in several colors such as reddish N7 and N0.5 of Neutral color, 10R3/6 and 10R3/10 of R color, 7.5B4/10 and 7.5B7/8 of B color and 5G8/6 of G color. The result suggests that roof color impedes the landscape of rural villages on the street. Based on the results, some roofs of rural villages were improved by the support of the government or the local governments but there are still many old roofs. The mixture of improved roofs and old roofs mainly contributed to impeding the landscape of rural villages and it was probably caused by the lack of systematic landscape plans by individual improvement of buildings. Therefore, it is necessary to devise systematic landscape plans in consideration of local identity and neighboring environment. In particular, the guideline for roof color influencing a street landscape should be established.

• Spatial Information Research
• /
• 제20권2호
• /
• pp.93-103
• /
• 2012

Recently metropolitan cities pursue multi centric urban spatial structure for sustainable development and efficient urban management. Thus, this study calculated population potential using data on population distributed among road nodes for the last 50 years, and based on the results. We measured the spatial variability of the multi centric structure of Busan Metropolitan City. According to the results, the multi centralization process has been continued up to recently in Busan Metropolitan City. As population potential is concentrated on sub centers, Hadan, Gupo and Haeundae areas were playing an increasingly powerful role as the center of the respective district, and Sasang and Dongrae had been losing their role as the center of their respective districts since 2000 and 1990, respectively. Additionally, in all the multi centric districts except Haeundae was observed the increase of oblongity, which is the change of spatial structure in an unbalanced way toward a specific area or direction.

• Journal of the Korean Institute of Landscape Architecture
• /
• 제33권2호
• /
• pp.16-31
• /
• 2005

This study was carried out to design a bridge-type ecological corridor plan in a forested neighborhood park affected by road construction in Dongjak-gu, Seoul. In order to study the site conditions, we analyzed topography, ecosystem structure, and user behavior and trail use. Existing vegetation was classified into 12 types. Based on a vegetation analysis, the Populus albaglandulosa and Robinia pseudoacacia communities, where planted species are dominant, were distributed extensively in the southern forest area. Planted areas with a single-layer structure of Korean landscape woody plants and Robinia pseudoacacia communities with a single-layer structure were distributed extensively in the northern forest and water-supply area. Based on a study of 28 quadrats, the similarity index between the multi-layer plant communities distributed in the southern forest and the single-layer planted areas was low. Twenty-four species of wild birds(355 individuals) were found in the survey area, including nine interior species and three urban species. The study of user behavior and numbers showed most users were walkers and few users were observed in the southern forest while most users were observed in the northern forest and water supply area. We selected some wild birds as model species to represent migrating species believed to use this park as an ecological corridor during migration. We suggested the new park plan include the following: improvement of vegetation structure for wildbird migration and habitat, connection of park trails for users and presentation of a landscape linked to nature.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 한국주거학회 2002년도 추계학술발표대회
• /
• pp.307-313
• /
• 2002

Urban style row-rise houses for rent have been supplied to the center of city from the 1950's first half The amount of stock is about 450,000 houses and occupies about 40％ in the private rented house. As for the structure, the 60％ of them is wooden-structure and the rest is non-wooden. Stocks of 57.5％ of the wooden-structure and 86％ of the non-wooden were built after 1981 years. It was 1981 years that the new earthquake-resistant standard was carried out, the improvement of stocks built before 1981 is necessary because those don't satisfy the present standard. To investigate the renovation possibility of urban style row-rise houses for rent, actual situation of two-story apartment at 2,4, and 5 Chome Taito-Ku in Tokyo was surveyed from July to November 2001. The number of building analyzed is 227 ridges among 234 ridges of the surveyed two-story building. 90％ of building analyzed is wooden structure. 1) The site of 88％ building surveyed is close to a road less than 4m width. It becomes the existing non-conformed building in the building construction act. It is impossible to make a renovation such as rebuilding, extension and remodeling because it requires the set back when renovating this type of non-conformed building, 2) The building built before 1981 is almost wooden-structure, and occupies 37％ of the building surveyed, and doesn't satisfy the present earthquake-resistant standard. An improvement of them is needed because the decrepitude of building proceeds. 3) 50％ of openings and 40％ of windows of the building surveyed doesn't use noncombustible materials. Though it becomes the existing non-conformed building, it can satisfy the present standard by replacing openings with noncombustible materials.