• Proceedings of the Korean Geotechical Society Conference
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• 2006.10a
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• pp.632-639
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• 2006

최근 들어 집중호우 등으로 인해 빈번해진 비탈면의 붕괴를 억지하기 위하여 비탈면 안정화기술이 급속하게 발전하고 있다. 특히 최근에는 신기술제도의 도입으로 비탈면 안정화를 위한 보강기술의 발전이 두드러지고 있다. 비탈면의 안정화를 위해서는 보강기술의 개발뿐만 아니라, 설계기준이나 설계기술, 유지관리기술, 예측기술 등 다양한 분야의 기술개발이 이루어져야 함에도, 최근 진행되고 있는 연구분야의 노력은 보강기술분야로 치우쳐 있는 실정이다. 이러한 관점에서 비탈면의 안정화를 위한 노력은 각 부분에서 균형적으로 비탈면의 안정화를 도모할 수 있는 기술개발 방향이 설정될 필요가 있다. 본고에서는 향후의 비탈면 안정화 기술 개발 방향 설정에 도움이 될 수 있도록 비탈면 안정화기술의 최근 동향을 파악하고, 비탈면의 안정화를 위하여 개선 및 개발되어야 할 필요가 있는 분야를 소개하고자 한다.

• Electric Engineers Magazine
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• s.356
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• pp.29-32
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• 2012

• Electronics and Telecommunications Trends
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• v.31 no.3
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• pp.20-31
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• 2016

위성항법 보강시스템은 항법위성인 GPS 제공 항법신호를 수신 처리하여 각종 오차 성분을 제거시킴으로써 산출된 위치정확도, 시스템 가용도 및 제공신호에 대한 무결성 등이 향상됨에 따라 항공분야, 해양분야 및 차량내비 등 육상분야에서 요구하는 위치정확도뿐만 아니라 보강 및 무결정정보 등을 특정 성능 요구를 만족시킬 수 있도록 제공하는 시스템이다. GPS 신호에 대한 오차를 보강한 메시지를 활용하는 매체를 무엇을 활용하는지에 따라 구분할 수 있는데 위성을 이용하면 위성기반 보강시스템(Satellite Based Augmentation System: SBAS), 지상망을 이용하면 지상기반 보강시스템(Ground Based Augmentation System: GBAS), 비행기를 이용하면 항공기반보강시스템(Aircraft-Based Augmentation System: ABAS)으로 일컫는다. 본고에서는 위성항법 보강시스템의 현황과 그 관련 기술에 대하여 기술하고 한다.

• The Science & Technology
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• s.477
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• pp.20-20
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• 2009

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.474-477
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• 2011

본 논문에서는 내진보강공법의 내진성능향상을 평가하기 위하여 진동대실험을 실시하였다. 실험 구조체는 비보강, 보강 구조체로 각각 실규모 크기의 구조체를 2개 제작하였다. 기둥 상, 중, 하부 및 보에 각각 Strain게이지, 가속도계를 설치한 후 설계펙트럼가속도 0.15g의 30~150%까지 가속도를 증가 시키면서 실험을 수행하였다. 그 결과 비 보강 구조체는 0.2g에서 최대 80cm균열이 발생하였으나 보강 구조체는 균열이 발생하지 않았다. Strain의 변화량에서는 비 보강이 보강보다 최대 1700%크게 나타났다. 가속도의 변화량은 비 보강이 176%크게 나타났다. 진동대 실험결과 본 내진보강공법이 내진성능향상에 지대한 영향을 주고 있음이 증명되었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5A
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• pp.719-727
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• 2008

The tensile and bond performance of GFRP rebar are different from those of conventional steel reinforcement. It requires some studies on concrete members reinforced with GFRP reinforcing bars to apply it to concrete structures. GFRP has some advantages such as high specific strength, low weight, non-corrosive nature, and disadvantage of larger deflection due to the lower modulus of elasticity than that of steel. Bridge deck is a preferred structure to apply FRP rebars due to the increase of flexural capacity by arching action. This paper focuses on the behavior of concrete bridge deck reinforced with newly developed GFRP rebars. A total of three real size bridge deck specimens were made and tested. Main variables are the type of reinforcing bar and reinforcement ratio. Static test was performed with the load of DB-24 level until failure. Test results were compared and analyzed with ultimate load, deflection behavior, crack pattern and width.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.349-356
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• 2008

Recently FRP (Fiber Reinforcement Polymer) is widely used for the strengthening of damaged RC beams. Although many tests were carried out to verify flexural capacity of RC beams strengthened with FRP sheet or plate, the behavior of strengthened RC beams has not yet clearly verified. To investigate the strengthening efficiency of the Near Surface Mounted Reinforcement (NSMR) technique experimentally and analytically, a total of 7 specimens have been tested. The experimental results revealed that specimens strengthened with NSMR improved the flexural capacity of RC beams. Also, while the NSMR specimens utilized CFRP reinforcement efficiently compared to the EBR (Externally Bonded Reinforcement) specimen, the NSMR specimens still have debonding failure between epoxy and concrete interface. This study has proposed the model to predict failure modes and failure loads. Good agreement was obtained between the predicted and the experimental results.

• Journal of the Korean Geotechnical Society
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• v.39 no.5
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• pp.41-50
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• 2023

This study reviewed the liquefaction reinforcement and ground reinforcement methods widely used domestically and abroad through construction method characteristics and analyzed the economic feasibility and reinforcement efficiency of each reinforcement method. The analysis results were used to evaluate the applicability of the appropriate reinforcement method for the liquefaction reinforcement of new and existing structures. As a result of evaluating the applicability of the reinforcement method based on the economic feasibility and reinforcement effect of each reinforcement method, the compaction method, which secures the construct ability by applying large equipment, is advantageous when reinforcing a new structure, and the low-fluidity mortar injection method (C.G.S method) and the high-pressure injection method (J.S.P method) are considered appropriate in the existing structure.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.1
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• pp.1-6
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• 2021

Concrete structures gradually age due to deterioration of materials or excess loads and environmental factors, and their performance decreases, affecting the usability and safety of structures. Although external tension construction methods are widely used among the reinforcement methods of old bridges, it is insufficient to identify the effects and effects of reinforcement depending on the level of aging. Therefore, in this study, a four-point loading experiment was conducted on the subject with the non-reinforced and external tensioning method to confirm the reinforcement effect of the external tensioning method, assuming the aging of the structure as a reduction in the compressive strength and tensile reinforcement of concrete, to analyze the behavior of the reinforcement and confirm the reinforcement effect. As a result of the experiment, it was difficult to identify the amount of reinforcement in the extreme condition due to early elimination of the anchorage. Therefore, compliance with the regulations on anchor bolts is required when applying the external tension reinforcement method. Crack load and yield load increased depending on whether external tension was reinforced, but before the crack, the stiffness before and after reinforcement was similar, making it difficult to confirm the reinforcement effect.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.699-714
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• 2022

The objective of this study is to suggest a safe and economical pillar reinforcement method when very near-twin tunnels with a minimum interval of 1 m passes through a soft zone such as weathered soil or weathered rock. A standard cross-sectional view of a two-lane road tunnel was applied to suggest a pillar reinforcement method for the very near-twin tunnels. The thickness of the pillar was 1 m. The ground condition around the tunnel was weathered soil or weathered rock. There were four reinforcement methods for pillar stability evaluation. These were rock bolt reinforcement, pre-stressed steel strand reinforcement, horizontal steel pipe grouting reinforcement, horizontal steel pipe grouting + prestressed steel strand reinforcement. When the ground condition was weathered soil, only the pillar reinforced the horizontal steel pipe grouting + prestressed steel strand did not failed. When the ground condition was weathered rock, there were no failure of the pillar reinforced the horizontal steel pipe grouting or the horizontal steel pipe grouting + prestressed steel strand. It is considered that the horizontal steel pipe grouting reinforcement played a role in increasing the stability of the upper part of the pillar by supporting the upper load applied to the upper part of the pillar.