• Journal of Korean Society of Steel Construction
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• v.23 no.6
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• pp.705-713
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• 2011

This study was conducted to assess the vibration capacity and the fire resistance capacity of a deck plate slab using an omega steel plate as the void deck plate. First, to evaluate the vibration capacity of the deck plate slab after the insertion of the omega steel plate, three 150mm specimens and three 200mm specimens were made using the slab depth as the main variable. Each specimen consisted of an existing deck plate and two specimens, using the topping depth as the variable according to the slab depth. Second, two real-size specimens were made to evaluate the fire resistance capacity. The results of the test showed that the steel-wire-integrated deck plate slab that was inserted in the omega steel plate did not have a vibration problem due to the void deck plate, because the natural frequency was 12.66-14.09 Hz in the vibration test, and each specimen satisfied the appraisal standards for the load capacity, heat block quality, and chloride inhibition for two hours in the fire resistance test. Consequently, the steel-wire-integrated deck plate slab that was inserted in the omega steel plate can be reduced using the concrete volume and can have higher vibration and fire resistance capacities, similar to the existing deck plate.

• Fire Science and Engineering
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• v.31 no.2
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• pp.1-8
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• 2017

A sandwich panel is a composite material composed of a double-sided noncombustible material and insulation core which is used in the inner, outer walls, and roof structure of a building. Despite its excellent insulation performance, light weight and excellent constructability, a flame is brought into the inside of the panel through the joint between the panels, melting the core easily and causing casualties and property damage due to the rapid spread of flame. The current Building Law provides that the combustion performance of finishing materials for buildings should be determined using a fire test on a small amount of specimen and only a product that passes the stipulated performance standard should be used. This law also provides that in the case of finishing materials used for the outer walls of buildings, only materials that secured noncombustible or quasi-noncombustible performance should be used or flame spread prevention (FSP) should be installed. The purpose of this study was to confirm the difference between the dangers of horizontal and vertical fire spread by applying FSP, which is applied to finishing materials used for the outer walls of buildings limitedly to a sandwich panel building. Therefore, the combustion behavior and effects on the sandwich panel according to the application of FSP were measured through the construction to block the spread of flame between the panels using a full scale fire according to the test method specified in ISO 13784-1 and a metallic structure. The construction of FSP on the joint between the panels delayed the spread of flame inside the panels and the flash over time was also delayed, indicating that it could become an important factor for securing the fire safety of a building constructed using complex materials.

• Fire Science and Engineering
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• v.31 no.6
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• pp.33-39
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• 2017

Composite panel refers to the particular plywood produced in a way of stacking the different kinds of material in sandwich form and adhering them using adhesives and is widely used as building material for its constructability and cost efficiency. But as the surface is finished with steel plate, fire extinguishing agent cannot reach to the core material because of such steel plate on surface which causes the difficulties in suppressing the fire as well as in fire-fighting activities due to collapse. This study, to deal with such problem, is intended to set the fire pipe in core material to prevent the fire from spreading and in a bid to achieve this using minimized fire water, water supply test device was fabricated to estimate the required water flow of fire extinguisher and consequently, optimal water flow (0.5 L/min) was determined through a full-scale fire test.

• Journal of Korean Society of Steel Construction
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• v.28 no.2
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• pp.109-120
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• 2016

Flexural tests of full-scale concrete-filled U-shape hybrid composite beams were conducted. Ordinary (SS400) and high-strength (SM570) steel plates were used in the web and in the bottom flange of U-shape steel section respectively. The primary objectives were to develop the hybrid section configuration with maximized flexural capacity and to investigate its flexural strength and deformation capacity. All the hybrid test specimens in this study exhibited the plastic moment capacity and resonable deformability. It is shown that the plastic stress distribution can be assumed in calculating the flexural strength of the proposed hybrid composite beams if the plastic neural axis is located within 15% of the total beam depth from the top of the composite slab. The procedure for computing the effective flexural stiffness of hybrid composite beams is also recommended based on test results.

• Journal of Korean Society of Steel Construction
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• v.26 no.4
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• pp.361-373
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• 2014

As the height and beam span of buildings built in the construction market increase, increasingly higher quality is being required of the construction materials. In response to this trend, 800MPa tensile strength class steel was developed in domestic company. Currently, experiments applying flexural member, compression member, and connections are continuously conducted, but a design guideline for high strength steel has yet to be established. Among those construction materials, for the high strength steel beam-to-column connections, the evaluation of implementing ductile connections for the high strength steel beam-to-column connections is producing pessimistic results and the number of related researches is inadequate because of the high yield ratio, which is the characteristic of high strength steel. This study on implementation of ductile connections made of high strength steel was conducted using the connection detail as the variable, for the purpose of enhancing the deformation capacity of high strength steel beam-to-column connections. Cyclic loading test and nonlinear finite element analysis were conducted with full-scale mock-up connection models with the applied connection details. As a result, the structural performance of high-strength steel beam-to-column connection with presented detail was contented with demand of Special Moment Frames of KBC standard.

• Journal of Korean Society of Transportation
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• v.21 no.1
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• pp.115-125
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• 2003

The concrete median barriers are the most popular safety appurtenance that can be installed on narrow medians and are effective in keeping uncontrolled vehicles from crossing into opposing lanes of traffic. It is necessary to install and maintain median barriers because it is very difficult to reserve enough room required for medians in KOREA. Also, concrete median barriers are accepted as the actual alternatives for median barriers, mostly because they require almost no maintenance even after serious collisions. Typical concrete median barriers are 810mm high and have 596mm high glare screens on top of them. However we have experienced a number of "climb" and "roll-over" accidents of heavy vehicles and most of all, there have been some serious accidents caused by the part of broken glare screens. So the improvement study of concrete median barriers started. Prior to this study, a new type of concrete median barrier was suggested which is 1,270mm high and has no glare screens on top of it. So it was required to compare the properties of various types of concrete median barriers including the new type to find the optimal type of concrete median barrier. In this study, we have evaluated the characteristics of four types of concrete median barriers (New Jersey type, F type, constant slope type, and wall type). We have performed many computer simulations for the evaluation of the crashworthiness of them, and through the simulations we have tried to find a proper type of concrete median barrier. Through the computer simulations, we evaluated the structural stability and safety of the four types of concrete median barriers. We confirmed the structural stability and safety of them But in regard to the probability of "roll-over" of heavy vehicles, the higher concrete median barriers showed better performances than the lower. As the result of this study a new type of concrete median barrier was recommended.

• Journal of the Korean Society for Library and Information Science
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• v.41 no.4
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• pp.331-346
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• 2007

The purpose of this study is to research into the characteristics of the printed hooks of ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary in Chosun dynasty by analyzing the types and forms of the existing printed books through the investigation of the bibliographic records of the books. To achieve this purpose, this study selected some of the 'Chak-pan' catalog(冊板目錄) printed in Chosun dynasty which has relatively clear and accurate history and investigated the block printing's condition of the printed books of ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary. In addition. a comprehensive book catalog of ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary was created by retrieving old book catalog from databases by several authoritative information centers and university libraries. Based on this catalog, this research created a new 'Union Catalog(綜合書目)' which contains bibliographies of the ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary through field investigations by identifying, picture-taking. and copying the real books. The new union catalog functions as the basis of the bibliographic analysis of this research.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5369-5377
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• 2014

Korean pagodas were constructed in the shape of a wood pagoda, brick pagoda, stone pagoda, etc. On the other hand, the currently remaining traditional pagodas are those having nonflammable materials, such as brick, stone, etc. Compared to the stone pagoda, there is data regarding brick pagodas, but there is little literature data on how to construct these pagodas. This appears to be because there are relatively few Korean brick pagodas currently remaining, they are locally restricted, the material limit is not overcome, pagoda's historical and regional problems have not been analyzed, and pagoda construction is centered on pagoda construction. Therefore, this study examined the local cultural characteristics on the construction of brick pagodas. As a result, cultural exchange between Korea and China was performed through the silk road and there was a marine route for cultural exchange. Such exchange was shared with the East Asia area as well, which can be found by comparing remains at related areas. Exchange with China can be mentioned as the selective exchange of local powers as well as blind learning. Second, brick pagoda were constructed in Korea because of the good quality soil easily. Uisang's Hwaeomjong was negotiated with the main power not agreeing with Buddhism, which was popularized and the local power. Third, brick pagoda construction was influenced by negotiation related between Balhae and Silla, in which the ethnic influence was locally affected and could be mentioned as being a culturally selective result transferred from China. As a result, brick pagodas can be oriented by forming a unitary state rather than a small country within China's influence range as well as cultural transfer through the silk road.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.2
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• pp.23-30
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• 2009

Crash cushions are protective devices that prevent errant vehicles from impacting on fixed objects. This function is accomplished by gradually decelerating a vehicle to a safe stop in a relatively short distance. Commonly used crash cushions generally employ one of two concepts to accomplish this function. The first concept involves the absorption of the kinetic energy of a moving vehicle by crushable or plastically deformable materials and the other one involves the transfer of the momentum of a moving vehicle to an expendable mass of material located in the vehicle's path. Crash cushions using the first concept are generally referred to as compression crash cushions and crash cushions using the other concept are generally referred to as inertial crash cushion. The objective of this research is the development of a compression-type crash cushion by employing the two concepts simultaneously. To minimize the number of full-scale crash tests for the development of the crash cushion, preliminary design guide considering inertial and frictional energy absorption was constructed and computer simulation was performed. LS-DYNA program, which is most widely used to analyze roadside safety features, was used for the computer simulation. The developed crash cushion satisfied the safety evaluation criteria for various impact conditions of CC2 performance level in the Korean design guide.

• Journal of Korean Home Economics Education Association
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• v.18 no.4 s.42
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• pp.103-126
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• 2006

This study was to develope and applicate the consumer education program with appropriate level for middle school students so that they could take systematic consumer education by using creative-discretionary activity. The procedure of this study was researching and analyzing the degree of learner's need and choosing the contents of education involved with the characteristics of adolescent consumers. This education program was performed at creative-discretionary activity class with the 3th grade of middle school. To evaluate the effect of education program, we compared with the difference of student's knowledge and attitude before and after this program was performed. Although there was no significant difference, student's knowledge and attitude was improved much better. And there marked a high satisfaction rate of 3.87 about the overall method of consumer education.