• Journal of the Korea Institute of Building Construction
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• v.24 no.1
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• pp.77-86
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• 2024

In this study, an evaluation was conducted for a total of 16 conditions to suggest an appropriate construction method for the construction joint of polyurea waterproofing membrane coating. It was analyzed that the longer the construction time difference, the higher the rate of water leaks through joints, and it was confirmed that water leaks could be prevented through primer construction. In addition, since the surface of polyurea exposed outdoors for a long period of time is deteriorated and weakened, it was analyzed that polishing the area increases surface damage and affects the formation of the interface. During maintenance construction, it would be desirable to apply a primer before construction, and it is believed that using the same urea-based material will ensure waterproofing stability.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.763-768
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• 2001

The purpose of this study is to research a specific material characteristics of top down concrete at column joint and to reduce column joint opening. Based on the established top down study, the experiment to apply an real construction case is performed. When the concrete placed into joint of top down column, raised air bubble is left as opening. This study is examined the incomplete packing reason in the top down column and found to air deflation method. The result of study is below (1) As the method to minimize column opening caused from confined air, it is required that an air exhaust port installation in joint column. (2) From air exhaust port installation, most of air bubble in column part is exhausted. As the concrete placing height is going up, air bubble size is going smaller.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4302-4309
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• 2012

Underground structures without the expansion joint in the settled intervals, the underground structures may suffer from structural crack and the water leakage thereby resulting in the occurance of the efflorescence. In this study, the performance of new expansion joint used in underground structures were verified. The spacing of expansion joint was defined by the finite element analysis. Expansion length, resistance and waterproofing performance of developed expansion joint were confirmed by experiment.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.109-110
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• 2009

This study is to evaluate the shear performance of joint between existing and new slab in apartment remodeling construction for enlarging existing slab. The horizontal joint parameters are consisted by steel pipe cotter, shear reinforcement, H-steel, stud bolt, and round shear key by concrete. And joint specimens will be tested to evaluate the shear performance of these parameters. If the joint detail have sufficient strength, it will be proposed the basic form on the design of joint parts.

• International Journal of Concrete Structures and Materials
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• v.5 no.1
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• pp.11-18
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• 2011

Carbonation in RC (reinforced concrete) structure is considered as one of the most critical deteriorations in urban cities. Although RC column has one mix condition, carbonation depth is measured spatially differently due to its various environmental and internal conditions such as sound, cracked, and joint concrete. In this paper, field investigation was performed for 27 RC columns subjected to carbonation for eighteen years. Through this investigation, carbonation distribution in sound, cracked, and joint concrete were derived with crack mappings. Considering each related area and calculated PDF (probability of durability failure) of sound, cracked, and joint concrete through Monte Carlo Simulation (MCS), repairing timings for RC columns are derived based on several IPDF (intended probability of durability failure) of 1, 3, and 5%. The technique of equivalent probability including carbonation behaviors which are obtained from different conditions can provide the reasonable repairing strategy and the priority order for repairing in a given traffic service area.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.447-450
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• 2005

A prefabricated composite hollow slab with perforated I-beams was suggested for the replacement of deteriorated concrete decks or the construction of new composite bridges with long-span slabs. Composite slabs with embedded I-beams have considerably higher stiffness and strength. For the application of prefabricated composite slabs to bridges, joints between slabs should satisfy the requirements of the ultimate limit state and the serviceability limit state. In this paper, three types of the detail for loop joints were selected and their structural performance in terms of strength and crack control was investigated through static tests on continuous composite slabs. A main parameter was the detail of the joint, such as an ordinary loop joint and loop joint with additional reinforcements. Even though there was no connection of the steel beams at the joints, the loop joints showed good performance in terms of strength. In terms of crack control, the loop joint with additional reinforcements showed better performance. In ultimate limit state, the continuous composite slabs showed good moment redistribution and ductility.

• Proceedings of the KSR Conference
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• 1998.11a
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• pp.24-29
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• 1998

To absorb the deformation of ,external live load, thermal gradient, shrinkage and creep in bridge structures and general structures, expansion joint has to be established. Especially expansion joint for high-speed railway bridge has to accomodate the static and dynamic forces and it not only has the durability of itself but also maintain the durability of structure by preventing the leakage of water. The actual used product of expansion joint for high-speed railway bridge is only ones made in France, Germany and Japan. In this study, the development process and test results of developed expansion joint are introduced which has the functional operation and durability enough to apply to high-speed railway bridges, roadway bridges and general structures. The tests consist of fatigue-durability test of 3 million times by high-speed rail load, leakage test and jack-up test for verifying the possibility of exchanging it. The performance of developed expansion joint satisfy the specification of Korea High Speed Rail Construction Authority.

• Computers and Concrete
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• v.22 no.3
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• pp.319-326
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• 2018

RC (Reinforced Concrete) members are always subjected to loading conditions and have construction joints when constructed on a big scale. Service life for RC structure exposed to chloride attack is usually estimated through chloride diffusion test in sound concrete, however the test is performed without consideration of effect of loading and joint. In the present work, chloride diffusion coefficient is measured in concrete cured for 1 year. In order to evaluate the effect of applied load, cold joint, and mineral admixtures, OPC (Ordinary Portland Cement) and 40%-replaced GGBFS (Ground Granulated Blast Furnace Slag) concrete are prepared. The diffusion test is performed under loading conditions for concrete containing cold joint. Investigating the previous test results for 91 days-cured condition and the present work, changing diffusion coefficients with applied stress are normalized considering material type and cold joint. For evaluation of service life in RC continuous beam with 2 spans, non-linear analytical model is adopted, and service life in each location is evaluated considering the effects of applied stress, cold joint, and GGBFS. From the work, varying service life is simulated under various loading conditions, and the reduced results due to cold joint and tensile zone are quantitatively evaluated. The effect of various conditions on diffusion can provide more quantitative evaluation of chloride behavior and the related service life.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.854-861
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• 2005

Studied accuracy and practical use possibility of joint measurement that using 3D laser scanner to rock slope. Measured joint of Rock slope and comparison applied 3 dimension laser scanner and clinometer. 3D laser scanning system preserves on computer calculating to 3 dimension coordinate scaning laser to object. and according to laser measurement method of interior, produce correct vector value from charge-coupled device(CCD) or laser reciver and telegram register and time measuring equipment. Create of object x, y, z point coordinates to 3 dimension space of computer. Such 3 dimension point datum (Point Clouds) forms relocate position informations that exist to practical space to computer space. Practical numerical values related between each other. Compared joint distribution and direction that measured by laser scanner and clinometer. By the result, Distribution of joint projected almost equally. Could get more joint datas by measurement of 3 dimension scanner than measured by clinometer. Therefore, There is effect that objectification of rock slope investigation data, shortening of investigation periods, investigation reduction of cost. could know that it is very effective method in joint measuring.

• Journal of the Korea Furniture Society
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• v.23 no.3
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• pp.290-297
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• 2012

Recently, interest in wooden construction have been growing by increasing needs and demands for eco-friendly and traditional wooden building(Hanok). Especially, Hanok has the technical development in manufacturing the mortise-tenon joint without fasteners(precut), so it could be called to modernization, industrialization and popularization. But the structural design and analysis of the structure were not regulated and had the difficulty to consider the variation of wooden member and to conduct the difficulty in the structural analysis and the design of the joint. In this study, the stiffness ratio of wooden mortise and tenon joint was evaluated according to the vertical loading, lintel and loading speed. The joint was distinguished in semi-rigid joint regardless of their factors. The stiffness ratio was 0.40 in vertical loading, 0.50 without vertical loading and 0.44 in horizontal loading with high speed. This study would be utilized to the structural analysis and design with structural analysis and design program.