• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.143-144
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• 2016

The core drilling method is considered to be the most effective and common method of assessing the compressive strength of concrete in existing reinforced concrete buildings for structural repair and retrofit. In general, core specimens within reinforcing bars are not permitted in the regulations with regard to assessing concrete strength even if the core specimens can contain the bars in some cases. The purpose of this study is to investigate the effects of the reinforcement arrangement on the concrete compressive strength as a basic research to propose the quantitative criteria of strength for core specimens containing reinforcements. To complete the basic research, cylinder specimens inserted in a variety of reinforcement arrangements were prepared and tested.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.605-610
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• 1997

An experimental investigation was conducted to examine the feasibility of Carbon Fiber Sheet(CFS), a kind of high strength fiber, for a repair and reinforcement method of concrete structures. The experimental program included tests of flexural beams different in wrapping method and amount of CFS. The beams were subjected to monotonic loading. Although the flexural strength for concrete members increases with wrapping methods of CFS., the reduction factor due to the distribution, amount bond of CFS should be completely examined. This study approached the effectiveness and application of CFS, along with reinforcement effects of CFS on reinforced concrete beams through tests. Test results indicated that the increase in the number of CFS layer caused the increase in strength of beams in strength.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.230-231
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• 2013

A fire outbreak in a reinforcement concrete structure looses the organism by different contraction and expansion of hardened cement pastes and aggregate, and causes cracks by thermal stress, leading to the deterioration of the durability. So, concrete reinforcement structure is damaged partial or whole structure system. Therefore accurate diagnosis of deterioration is needed based on mechanism of fire deterioration in general concrete structures. Fundamental information and data on the properties of concrete exposed to high temperature are necessary for accurate diagnosis of deterioration. In this study, consider case of investigation methods and repair work in fire damaged structure concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.200-201
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• 2013

This study is interested in manufacturing the concrete surface impregnants including tetra ethyl ortho silicate, alkali silicate for the repair of the exposed concrete and the color concrete requiring the advanced function in view of the concrete appearance. The surface layer change and porosity properties was tested for the review of application. The result of this study show that the effective silicate are tetra ethyl ortho silicate and alkali silicate t. The adhesion in tension is slightly increased but the reinforcement of concrete substrate is slight. So, the concrete impregnant of this study is more desirable for the improvement of durability rather than the reinforcement.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.16-18
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• 2013

A fire outbreak in a reinforcement concrete structure looses the organism by different contraction and expansion of hardened cement pastes and aggregate, and causes cracks by thermal stress, leading to the deterioration of the durability. So, concrete reinforcement structure is damaged partial or whole structure system. Therefore accurate diagnosis of deterioration is needed based on mechanism of fire deterioration in general concrete structures. Fundamental information and data on the properties of concrete exposed to high temperature are necessary for accurate diagnosis of deterioration. In this study, consider case of investigation methods and repair work in fire damaged structure concrete.

• Journal of Korean Foot and Ankle Society
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• v.10 no.2
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• pp.259-263
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• 2006

The acute Achilles tendon rupture usually occurs to the people who participate in sports-related activities between 30 and 40 years of age. Recently surgical repair is the standard treatment in acute Achilles tendon rupture. After the Achilles tendon rupture in the left ankle, a 30-years old young man had been suffered from re-rupturing within three months after the primary repair. 2 years later, right-side Achilles tendon was reruptured after primary repair consequently. In the revision surgery, we performed V-Y advancement of the gastrocnemius-soleus fascia and reinforcement of the semitendinosus tendon. None of the English-literature was reported about using the semitendinosus tendon in revision surgery of the Achilles tendon retear previously. Therefore, we report this case and surgical technique because of the simple technique and the excellent results.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.6_2
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• pp.861-872
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• 2021

An efficient cost management is important for the domestic social overhead capital(SOC) based on a long lifecycle after 30 years since completion. Maintenance in South Korea have had the restrictions of consistency and suitability of decision-making by the establishment of a budget plan based on the company estimate and repair and reinforcement methods determined by the inspection and diagnosis engineers' subjective determination for each facility. To resolve this issue, the Korea Institute of Civil Engineering and Building Technology is currently in development of a methodology to propose an optimum maintenance method according to the damage of components by artificial intelligence. This study has deduced the primary factors by analyzing information generated during bridge maintenance and management as a prior step for the development of technologies, and conducted a preliminary analysis to select the optimum artificial intelligence technology.

• Journal of the Korean Recycled Construction Resources Institute
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• v.12 no.2
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• pp.111-120
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• 2024

This paper presents a study aimed at developing repair materials for emergency slope stabilization after disasters such as floods. The research assessed how different mix ratios of fly ash and reinforcement with basalt fibers affect the basic quality properties of mortars. Optimal amounts of fly ash were selected based on these properties, and appropriate amounts of chemical admixtures and thickeners were determined to enhance the quality attributed to the basalt fiber mixture. Notably, high-volume fly ash reduced the need for high-performance water reducers and improved workability, known benefits that also helped mitigate fiber ball issues in conjunction with the effects of thickeners. The experimental results indicated that the developed repair materials could potentially be used for emergency repairs, with a focus on initial age strength. This research aims to provide foundational data for repair materials used in future emergency slope stabilizations.

• Smart Structures and Systems
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• v.5 no.4
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• pp.443-455
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• 2009

The use of fiber reinforced polymer (FRP) reinforcement in concrete structures has been on the rise due to its advantages over conventional steel reinforcement such as corrosion. Reinforcing steel corrosion has been the primary cause of deterioration of reinforced concrete (RC) structures, resulting in tremendous annual repair costs. One application of FRP reinforcement to be further explored is its use in RC frames. Nonetheless, due to FRP's inherently elastic behavior, FRP-reinforced (FRP-RC) members exhibit low ductility and energy dissipation as well as different damage mechanisms. Furthermore, current design standards for FRP-RC structures do not address seismic design in which the beam-column joint is a key issue. During an earthquake, the safety of beam-column joints is essential to the whole structure integrity. Thus, research is needed to gain better understanding of the behavior of FRP-RC structures and their damage mechanisms under seismic loading. In this study, two full-scale beam-column joint specimens reinforced with steel and GFRP configurations were tested under quasi-static loading. The control steel-reinforced specimen was detailed according to current design code provisions. The GFRP-RC specimen was detailed in a similar scheme. The damage in the two specimens is characterized to compare their performance under simulated seismic loading.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.2
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• pp.135-143
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• 2002

This study is to investigate its use by applying stainless steel wire mash reinforcement method of construction, which is newly developed, on the high strength concrete beam mixed with polymer-steel fiber. In this test, it is investigated and observed such as follows: the ultimate load, the initial flexure crack load, the initial diagonal tension crack load, the relation between load and deflection, load-strain relation, and also crack growth and fracture aspect by increasing load. The results of this test are; first, the stainless steel wire showed some useful reinforcement effects in multiplying the steel's resisting force of moment to the tensile force of beam or slab: second, the promoting strength and internal force was made in the process of the integration at the same reaction by using the penetrating polymer-mortar with an excellent durability and physical property. On the basis of this results, because such instances in applying stainless steel wire Mash reinforcement method of construction have been few so far, through the experimental investigation such as this test over and over again, the efficient and useful method must be developed for the practice.