• Fire Science and Engineering
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• v.25 no.3
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• pp.91-98
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• 2011

This study is about fire resistance performance of wood framed lightweight wall including a middle lintel as a traditional wall form in Korea. The target wall is non-loadbearing system which constructed with $38{\times}89$ mm ($2"{\times}4"$) wood frame and fireproof gypsum board covering, including a middle lintel made of $150{\times}150$ mm section glue-laminated timber. As a test results, all specimens have showed fire resistant performance over 90 minutes and tests were maintained until flame occuring on Specimen-l, 2, 3 at 91 min, 97 min and 98 min respectively. Fire resistance of the heat side gypsum board was 45 minutes and charring rate of middle lintel was equivalant with that of usual timber. The wood stud inside wall system showed relatively quick combution characteristic when exposed to high temperature with no temperature rising delaying time caused by moisture evaporation because of the dehydration preceded during the early period of fire side gypsum board resist to heat.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.135-140
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• 2005

There are cofferdam and watertight wall to prevent of circulation or pollution during building of ocean structures like a dam and bridge in the harbors area and the sea. Inflow fluid and base of structure is important thing as one of the structural design factors for this interception wall like a cofferdam and watertight wall. In this study, it is revealed that at least 500 instantaneous velocity field data are required for ensemble average to get reliable turbulence statistics. The turbulent shear flow around a surface-mounted vertical wall was investigated by using the two-frame PIV(CACTUS 3.1) system and Mean velocity distributions have also been measured in the whole flow field.

• Korean Journal of Construction Engineering and Management
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• v.24 no.4
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• pp.14-24
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• 2023

The purpose of this study is to develop a prototype curtain wall with improved seismic performance and to verify the seismic performance by conducting an inter-floor displacement test. To this end, a prototype of the curtain wall was manufactured and a displacement similar to the earthquake load was induced, and then the damaged state of the curtain wall was checked. As a result of the first test, the frame and glass of the curtain wall were not damaged, but the Weather Sealant was partially damaged. As a result of the second test, there was no problem of glass breakage in seismic class (special), seismic class (I), seismic class (II), and AAMA 501.6. Through this experiment, the seismic performance of the curtain wall prototype was verified.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.89-98
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• 2017

The floor heating method generally uses a wet construction method including the installation of resilient material, lightweight foam concrete, heating piping, and finishing mortar. Such a wet construction method not only delays other internal finishing processes during curing period for two mortar pouring process, but also has a disadvantage that it is difficult to replace the floor heating layer when it deteriorated because it is integrated with the frame. Dry floor heating construction method can be a good alternative in that it can solve these defects. Conversely, when it applied to the wall structure that is vulnerable to the interlayer noise compared with the column-beam structure, the question about the heavy-impact sound(HIS) insulation performance is raised. Therefore, conventional dry floor heating method is hard to apply to the wall structure apartments. Therefore, for the purpose to improve the applicability of dry floor heating method in wall structure apartments, this study investigated the change of floor impact sound, especially HIS insulation performance which is one of the required performance for the floor structure. This study tried to examine whether the change of heavy-impact sound pressure level(SPL) shows a tendency at the significant level according to the shape and mass of the floor structure. Through filed experiments on wall structure apartment, this study confirmed that the form of the raised floor shows better HIS insulation performance than the fully-supported form. In addition, it was also confirmed that the HIS insulation performance increases with the mass on the upper part. Moreover, this study found the fact that a mass of about 30 kg/m² or more should be placed on the upper structure to reduce the heavy-impact SPL according to the bang machine measuring method. Although this study has a limit due to insufficient experiment samples, if the accuracy of this study is increased, it will contribute to the diffusion of dry floor heating by setting the HIS insulation performance target and designing the dry floor heating structure that meets the target.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.2
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• pp.59-65
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• 2000

In this paper the comparison of the first order approximation schemes such as SLP(sequential linear programming) CONLIN(convex linearization) MMA(method of moving asymptotes) and the second order approximation scheme SQP(sequential quadratic programming) was accomplished for optimization of nonlinear structures. It was found that MMA and SQP are the most efficient methods for optimization. But the number of function call of SQP is much more than that of MMA. Therefore when it is considered with the expense of computation MMA is more efficient than SQP. In order to examine the efficiency of MMA for complex optimization problem it was applied to the helicopter tail boom con-sidering column buckling and local wall buckling constraints. it is concluded that MMA can be a very efficient approxima-tion scheme from simple problems to complex problems.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.236-237
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• 2014

Recently, it changes to the frame construction in the wall type structure for the life span improvement of the apartment house of our country. The execution of the light panel increased while the execution of the frame construction increased. Therefore, the density and absorption ratio of the magnesium oxide matrix according to the wood flour amount of addition ratio property try to be analyze for the lightweight of the surface material of the light panel. The test result, the density has been declined as the addition ratio increase of the wood flour. In the case of the water absorption ratio, water absorption ratio has been increased as addition ratio increase of wood flour. However, wood flour addition ratio 15% determined the most appropriate when considering the density and water absorption ratio.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.139-140
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• 2011

The government encourages adoption of Rahmen structure design to ensure efficient management of national resources. However, in comparison with bearing-wall structure, Rahmen structure requires higher unit construction cost and present challenges in terms of securing adequate floor area ratio and floor height. That is why project clients have been disinterested in adoption of Rahmen structure design. Therefore, we have attempted to find factors having influence on decline of project viability for Rahmen structure. This study will be utilized as a basic reference study for promotion of Green Frame design which is a composite PC structure already developed.

• International Journal of Concrete Structures and Materials
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• v.7 no.2
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• pp.135-153
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• 2013

This study investigates the direct displacement based design (DDBD) approach for different types of reinforced concrete structural systems including single moment-resisting, dual wall-frame and dual steel-braced systems. In this methodology, the displacement profile is calculated and the equivalent single degree of freedom system is then modeled considering the damping characteristics of each member. Having calculated the effective period and secant stiffness of the structure, the base shear is obtained, based on which the design process can be carried out. For each system three frames are designed using DDBD approach. The frames are then analyzed using nonlinear time-history analysis with 7 earthquake accelerograms and the damage index is investigated through lateral drift profile of the models. Results of the analyses and comparison of the nonlinear time-history analysis results indicate efficiency of the DDBD approach for different reinforced concrete structural systems.

• Steel and Composite Structures
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• v.1 no.3
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• pp.341-354
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• 2001

This paper provides a state-of-the-art review on advanced analysis models for investigating the load-displacement and ultimate load behaviour of steel and composite frames subjected to static gravity and lateral loads. Various inelastic analysis models for steel and composite members are reviewed. Composite beams under positive and negative moments are analysed using a moment-curvature relationship which captures the effects of concrete cracking and steel yielding along the members length. Beam-to-column connections are modeled using rotational spring. Building core walls are modeled using thin-walled element. Finally, the nonlinear behaviour of a complete multi-storey building frame consisting of a centre core-wall and the perimeter frames for lateral-load resistance is investigated. The performance of the total building system is evaluated in term of its serviceability and ultimate limit states.

• Earthquakes and Structures
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• v.11 no.1
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• pp.179-193
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• 2016

The effectiveness of 100/30, 100/40 and SRSS directional combination rules on the response of asymmetric setback buildings is examined. Because of the irregularity in setback buildings, the maximum seismic response would be correlative with the direction of earthquake. To verify the directional combination rules of mode superposition methods, the time history analyses of setback buildings to real earthquake records are carried out. Example analyses have been used to compare the validty and accuracy of SRSS and percentage methods for frame and dual frame-wall systems.