• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.5
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• pp.639-646
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• 2021

In this study, we located concrete substratum covered by oyster shells in the coastal area of Gijang-gun, Busan, South Korea, and monitored changes in coverage of macroalgae for approximately a year from January 2020 to determine the potential for sea forest restoration and resourceization of the oyster shells. At the start of monitoring, we observed that macroalgae coverage of the oyster-shell-covered concrete substratum (treatment) was 10 - 80 %, whereas no macroalgae were attached to the normal concrete substratum (control). By November, macroalgae coverage of the treatment had increased by 49 % compared to that of the control. We concluded that covering oyster shell on a sea forest reef can promote macroalgae establishment and the possibility of sea forest restoration by the resourceization of oyster shells.

• 레미콘
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• no.1 s.46
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• pp.48-59
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• 1996

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.147-149
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• 2019

해수 온도의 상승과 해양 오염의 증가로 근래 국내 해안에서도 갯녹음이 확산되면서 바다숲이 축소되고 있다. 특히, 온난류의 유입에 의한 무절 석회조류의 난입과 해수에 함유 농도가 증가한 칼슘이 석출되고 해저 암반을 뒤덮어 해조류의 포자 활착 공간을 없애는 백화현상이 확산되면서 바다의 사막화 현상이 가속화되고 있다. 본 연구에서는 해조류의 포자가 빠르게 활착하여 안전하게 생장할 수 있는 공간을 제공하기 위한 새로운 방안으로, 먼저 육상에서 모판의 기능을 제공하여 해조류의 포자를 착상하여 성장시킨 후 해저로 이식하는 것으로 바다숲과 해안의 환경을 효과적으로 복원하기 위한 방안으로 다공성 기질 생태 플랫폼을 디자인하고 이의 특성 및 활용 방안을 제시하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.495-500
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• 2002

The purpose of this study is to develop and to apply this permanent cement mortar form as one of those system forms to improve existing form's problems. (1) In the fire proof test with combined specimen, the fire proof covering including form section thickness is satisfied with the fire proof criterion. It is considered that form section thickness has no problem (2) The suitable method of normal pressure steam curing for the form's mass production is 4 hours in 65℃ considering production cost, the silica fume admixture is economic.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.825-828
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• 2008

Along with elevation of life of modern persons and living, interest for living environment and concrete rose by new request augmentation about health. and the qualitative-quantitative estimation for environment is required. This studies applied sense method of examination that measure fetid offensive smell strength using person's rear trail who is healthy by basis valuation method about concrete air environment. and this study Presented offensive odor estimation processor of cement mortar. Measured fetid degree that cement can happen at early hydration process step.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.613-616
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• 2008

This study is about appling non-exposure waterproofing method which combines the Cement Polymer Modified Waterproof Membrane coating and Selfadhesive Rubberized Asphalt sheet to the Roof Structure, Because there are a lot of problems in previous methods. So We had the performance tests using waterproofing method which combines two materials, and we analyzed the results. This study showed us very important results. We had bond strength test and tensile test under high, normal and low temperature, and the results were successful. And we also tested for coping with crack and movement. We found that tested materials were safe in those conditions. I think that Non-Exposure waterproofing method which combines the Cement Polymer Modified Waterproof Membrane coating and Selfadhesive Rubberized Asphalt sheet is available to concrete structure.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.729-732
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• 2008

Recently the attention against the indoor air quality that could affect health and comfort of building becomes intensively, the efforts for a problem solving is advanced with many sidedness. The research which it mixes the activated carbon and the functional catalyst materials that will be able to dissolve foul air absorbed by activated carbon in concrete with application technique of existing differently examined the basic physical properties and the removal ratio of formaldehyde so that it analyzed the effect of air purge. The test results in addition quantity increase of the activated carbon the slump showed the tendency which it decreased and the compressive strength appeared with no much difference. The test result removal ratio of formaldehyde was measured until the maximum 80%.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.416-424
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• 2023

Concrete emits a large amount of carbon dioxide throughout its life cycle, and due to the societal demand for carbon dioxide reduction, research on storing carbon dioxide in concrete in the form of minerals is ongoing. In this study, cyanobacteria, which absorb carbon dioxide through photosynthesis and fix it as calcium carbonate, were applied to a porous concrete substrate, and the changes in the properties of the concrete substrate due to their special environmental curing condition were analyzed. The results showed that the calcium carbonate precipitation by the microorganisms was concentrated in the light-exposed surface area, and most of the precipitation occurred in the cement paste part, not in the aggregate. This microbially induced calcium carbonate precipitation enhanced the mechanical performance of the paste and improved the overall compressive strength as the curing age progressed. In addition, the increase in microbial biofilm and calcium carbonate improved the pore structure, which influenced the reduction in water permeability.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1083-1088
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• 2001

To do performance evaluations about inorganic permanent form mixed in admixture(fly ash, silica fume) and after placed concrete, it is examined reinforcement materials in the permanent form from shear strength, bond strength and flexural strength tests. In this study, permanent form was inserted with reinforcement metal fitting is strength-tested in several method. The result of this study is belows. ⑴ In bond strength test, Most specimens are satisfied with criterion-6 kgf/$cm^{2}$ ⑵ Irrelative with the inserted metal fitting's shape, unevenness and aggregate, Permanent form and after placed concrete have good condition in the shear strength test. ⑶ In flexural test, there is no drop out of permanent form. Most cracks are located in nearby the strain point

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.139-144
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• 1995

It is the aim of this study to introduce the performance and application of new repair system for the exterior wall by durability failure caused seasand especially. The elementary performance of this repair system is as follows (1)All the layer in the repair are cement based, same with the mother conrete (2)this repair system use SBR admixture (3)This cement and mortar powder for this repair system are premixed and ready to use just adding admixture at the job site.