• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 연약지반처리위원회 학술세미나
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• pp.1-11
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• 2000

The use of Compaction Grouting evolved in 1950's to correct structural settlement of buildings. Over the almost 50 years, the technology has been developed and is currently used in wide range of applications. Compaction Grouting, the injection of a very stiff, 'zero-slump' mortar grout under relatively high pressure, displaces and compacts soils. It can effectively repair natural or man-made soil strength deficiencies in variety of soil formations. Major applications of Compaction Grouting include densifying loose soils or fill voids caused by sinkholes, poorly compacted fills, broken utilities, improper dewatering, or soft ground tunneling excavation. Other applications include preventing liquefation, re-leveling settled structures, and using compaction grout bulbs as structural elements of minipiles or underpinning. In this paper, on the basis of the case history constructed in this year, a study has been performed to analyze the basic mechanism of the Compaction Grouting. Also, the effectiveness of the ground improvement and the bearing capacity of the Compaction Pile has been verified by the Cone Penetration Test(CPT) and Load Test. Relatively uniform Compaction grouting column could be maintained by planning the Quality Control in the course of grouting. And, the Quality Control Plan has been conceived using grout pressure, volume of grout and drilling depth.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 연약지반처리위원회 학술세미나
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• pp.1-13
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• 1999

The use of Compaction Grouting evolved in the 1950's to correct structural settlement of buildings. Over the almost 50 years, the technology has developed and is currently used in wide range of applications. Compaction Grouting, the injection of a very stiff, 'zero-slump' mortar grout under relatively high pressure, displaces and compacts soils. It can effectively repair natural or man-made soil strength deficiencies in variety of soil formations. Major uses of Compaction Grouting include densifying loose soils or fill voids caused by sinkholes, poorly compacted fills, broken utilities, improper dewatering, or soft ground tunneling excavation. Other application include preventing liquefaction, re-leveling settled structures, and using compaction grout bulbs as structural elements of minipiles or underpinning. The technique replaced slurry injection, or 'pressure grouting', as the preferred method of densification grouting. There are several reasons for the increased use of Compaction Grouting which can be summarized in one word: CONTROL. The low slump grout and injection processes are usually designed to keep the grout in a homogeneous mass at the point of injection, while acceptable in some limited applications, tends to quickly get out of control. Hydraulic soil fracturing can cause extensive grout travel, often well beyond the desired treatment zone. So, on the basis of the two case history constructed in recent year, a study has been peformed to analyze the basic mechanism of the Compaction Grouting and verify the effectiveness of the ground improvement using some test methods.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.125-131
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• 2005

Recently, to improve condition car park, using surface finishing material for variety color and property epoxy resin, urethane, cement mixed resin mortar or polymeric resin, and so on. However, it is frequent noise and wear out of tier and waterproofing materials, when the car slip or stop in car park, To minimize these cases, It is necessary that reduction of repair cost through performance long term durability of surface finishing material, improvement inside condition such as reduce dirty and car accident and ensurance the expected life of concrete slab in car park. Especially, we have not any tech for quality control, construction tech, production technology for car park surface materials, that's why park slab is not safety and suffer a loss. For this problems, this paper is to test surface finishing materials and as that result, suggest quality standard in the car park.

• 콘크리트학회지
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• 제10권6호
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• pp.161-168
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• 1998

본 연구는 수직전단하중에 대한 프리캐스트 바닥판간 이음부거동을 규명하고 수직전단력 전달에 유리한 이음부 구조도출을 위해 female-female 형식의 이음부를 제안하고, 실험 및 유한요소해석을 수행한 것이다. 경사각, 이음부깊이/높이 및 구속응력을 변수로 총 18개의 실험체에 대한 실험 및 유한요소해석결과 ,이음부의균열저항성 개선을 위해서는 경사각이 60。, D/H가 1/4일 경우가 유리하며 측방향구속으로 이음부를 압축상태로 유지하는 것이 이음부 균열방지에 효과적임을 알았다.

• 한국철도학회논문집
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• 제2권4호
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• pp.9-19
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• 1999

The use of compaction grouting evolved in 1950's to correct structural settlement of buildings. Over the almost 50 years, the technology has been developed and is currently used in wide range of applications. Compaction grouting, the injection of a very stiff, 'zero-slump' mortar grout under relatively high pressure, displaces and compacts soils. It can effectively repair natural or man-made soil strength deficiencies in variety of soil formations. Major applications of compaction grouting include densifying loose soils or fill voids caused by sinkholes, poorly compacted fills, broken utilities, improper dewatering, or soft ground tunneling excavation. Other applications include preventing liquefaction, re-leveling settled structures, and using compaction grout bulbs as structural elements of minipiles or underpinning. In this paper, on the basis of the case history constructed in this year, a study has been performed to analyze the basic mechanism of the compaction grouting. Also, the effectiveness of the ground improvement and the bearing capacity of the compaction pile has been verified by the Cone Penetration Test(CPT) and Load Test. Relatively uniform compaction grouting column could be maintained by planning the quality control in the course of grouting. And, the Qualify Control Plan has been conceived using grout pressure, volume of grout and drilling depth.

• 한국구조물진단유지관리공학회 논문집
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• 제6권2호
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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.

• Geomechanics and Engineering
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• 제25권2호
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• pp.123-134
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• 2021

In this paper, the carbon fiber reinforced plastic (CFRP) grids embedded in polymer cement mortar (PCM) shotcrete (CFRP-PCM method) was conducted to repair the degraded tunnel linings with a cavity. Subsequently, the reinforcing effect of the CFRP-PCM method under different degrees of lining deterioration was quantitatively evaluated. Finally, the limit state design method of the M-N interaction curve was conducted to determine whether the structure reinforced by the CFRP-PCM method is in a safe state. The main results indicated that when the cavity is at the shoulder, the lining damage rate is more serious. In addition, the remarkably reinforcing effect on the degraded tunnel linings could be achieved by applying a higher grade of CFRP grids, whereas the optimization effect is no longer obvious when the grade of CFRP grids is too high (CR8); Furthermore, it is found that the M-N numerical values of the ten reinforcing designs of the CFRP-PCM method are distributed outside the corresponding M-N theoretical interaction curves, and these designs should be avoided in the corresponding reinforcing engineering.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.14-15
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• 2021

Recently, the size of tiles used for bathroom walls in apartment houses is gradually increasing in size. The problem is that when these large-sized tiles are attached by the sticking method, due to the nature of the method, there is a concern about the stability of the attachment to the part (pupil) where the tile and the adhesive are not attached. The problem is serious as it leads to lawsuits in the outbreak court. In addition, it is urgent to verify the adhesion stability of the sticking method because secondary damage occurs due to a safety accident caused by the falling of the tile. Ministry of Land, Infrastructure and Transport [Investigation of defects in apartment houses, calculation of repair cost and defect determination criteria] ① The tile adhesion strength is 0.39N/mm² or more and ② It is specified to fill 80% or more of the base area of the tile backside, but this is currently trendy. It is considered that large-sized tiles need to be verified from multiple angles, and as part of that, we intend to verify the adhesion stability according to the area to be attached to large-sized tiles.

• 헤리티지:역사와 과학
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• 제53권4호
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• pp.100-117
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• 2020

국보 제101호로 지정된 원주 법천사지 지광국사탑은 조성 후 수차례 이전 및 이건되었는데, 특히 한국전쟁 시 폭격으로 인한 심각한 훼손으로 1957년 전면적인 해체·보수가 이루어졌다. 당시 재료 및 수리 내용이 남아있지 않지만 보존 처리를 진행하면서 지광국사탑에 사용된 다양한 형태의 금속재료를 확인하였다. 각 부재를 연결하는데 꺽쇠 및 앵커볼트 외에 두께 9mm의 원형철근이 주로 사용되었으며, 부재와 모르타르 복원재를 연결하기 위해 다양한 두께의 원형철근과 철사 등이 사용되었다. 건축물로 분류되는 석탑에 통상적으로 사용되는 이형철근이 아닌 매끈한 표면의 원형철근이 사용되었다. 이는 모르타르 복원 시 재료가 가진 부착 강도와 결합력 강화를 위해 재료의 형태를 변형시키고, 서로 교차시켜 결속하고 불규칙적으로 꼬아 단면적을 늘리는 등 재료의 단점을 보완한 것으로 확인되었다. 또한 금속학적 분석법을 적용하여 알아본 결과 전체적으로 탄소 함량이 낮은 아공석강 소재로 사용하여 제작하였다. 미세조직 내에는 불규칙한 크기로 분포하는 방울 형태의 비금속개재물이 다수 포함되어 있으나 전체 성분에는 영향을 미치지 않을 정도의 미량으로 포함되어 있다. SEM-EDS의 면 분석으로 검출되지 않는 망간(Mn)과 황(S)이 정량 분석 및 EPMA 분석법으로 확인한 결과 망간황화물(MnS)로 시료의 형태와 관계없이 미세조직 결정립 내에 고르게 분포하고 있다. 철물의 형태 제작 후 작업의 용이성을 위해 2차로 균질화 등 열처리를 실시한 것으로 보여지며, 철물의 두께가 얇아질수록 포함된 탄소 함량이 감소하고 탄성과 신장률이 증가하는 특성에 따라 복원 작업 순서를 정하고 다양한 형태의 철물을 사용한 것으로 보인다.

• 자원환경지질
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• 제56권1호
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• pp.103-114
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• 2023

공주제일교회 기독교박물관은 1931년에 초축되었으며 한국전쟁으로 상당 부분 파손되었으나 벽체와 굴뚝 등이 보존되었다. 이 건물은 1956년 예배당을 재건하며 신축이 아닌 파손된 부분의 보수를 통해 원형을 유지하고 있다는 점에서 건축학적으로 높은 가치가 있다. 스테인드글라스는 1979년에 설치하였으며, 덩어리유리를 사용하는 달드베르(Dalle de Verre) 방식으로 큰 의미가 있다. 그러나 일부 스테인드글라스에서는 다양한 균열과 쪼개짐이 나타나고 색유리를 지지하는 줄눈에는 수직 및 수평균열이 확인되는 등 부분적인 손상을 입었다. 스테인드글라스의 구조재로는 철제 틀과 이를 충전한 시멘트 모르타르가 사용되었으며, 부분적으로 풍화작용에 따라 철제의 부식과 모르타르의 균열 및 입상분해가 나타난다. 줄눈재에서는 Ca과 S의 함량이 높아 석고를 혼화재로 사용하였음을 지시하며, 석고는 능형으로 성장하며 다발모양을 이루고 있는 것으로 보아 재결정작용을 거친 것으로 판단된다. 줄눈재의 초음파속도 모델링 결과, 입구 좌우창의 속도는 800~1,600㎧ 범위로 상대적으로 취약하며, 제단의 좌창 우측 하단과 중앙창 좌측 상단도 1,000~1,800㎧로 나타나 상대적으로 낮은 물성을 보였다. 또한 줄눈재와 표면오염물에서는 석회 모르타르의 중성화에서 생성되는 석고화합물이 검출되었다. 이와 같은 염류는 동결 및 융해작용에 따라 줄눈재의 손상을 일으킬 수 있어 적절한 예방보존이 필요하다. 스테인드글라스와 줄눈재에는 다양한 손상유형이 복합적으로 나타나고 있어 임상실험을 통해 맞춤형 보존처리를 검토해야 할 것이다.