• Title/Summary/Keyword: Seohae

Search Result 60, Processing Time 0.023 seconds

Studies on the Leaf Photosynthesis of Salt-Stressed Rice Cultivars (염류처리에 따른 벼의 개엽광합성에 관한 연구)

  • 조동하
    • Korean Journal of Plant Resources
    • /
    • v.7 no.1
    • /
    • pp.97-101
    • /
    • 1994
  • The effects of NaCl salinity on the leaf photosynthesis and water relation of two cultivars of rice(Oryza sativa L.) , the salt-tolerant cultivar Seohae and the salt-senstive cultivar Iri-380 were exam-ined. Two cultivars of rice were grown for 14 days in nutrient solution at SOmM NaCl. Comparing theieaf Na content of two cultlvars, Seohae showed high accumulation of Na content in the leaf blade, while Iri-380 showed low. The Na content in leaf blade reduced the rate of leaf photosynthesis. Salt-tolerant cultivar Seohae was less decreased the rate of leaf photosynthesis than salt- sensitive cultivarIri-380. And Seohae showed larger decreased the osmotic potential in the leaves than Iri-380. This in-dicates that in the salt-tolerant cultivar, osmotic adjustment is developed under saliniEation.

  • PDF

Experimental Study on Seismic Performance Evaluation of Piers in Seohae Grand Bridge (세해대교 PSM교 교각의 내진성능 평가에 관한 실험적 연구)

  • 손혁수
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2000.04a
    • /
    • pp.319-326
    • /
    • 2000
  • The purpose of this study is to evaluate seismic performance of reinforced concrete pier columns in Seohae Ground Bridge. Since the bridge was designed before preparing the seismic design specification the bridge columns of hollow hexagonal section were designed and constructed with insufficient seismic reinforcement details such as longitudinal and transverse reinforcement lap-splices. In order to take the necessary measures to improve its seismic performance experimental study was performed by small-scale test for the bridge columns, From the quasi-static test for small-scale column specimens the lap-splices were not critical for overall behavior of the column if sufficient lap-splice-length was provided. The test results of failure mode effective stiffness ductility and equivalent viscous damping ratio are presented.

  • PDF

Completing the Seohae Grand Bridge Construction Supervision (서해대교 감리를 마치며)

  • 전준수
    • Journal of the Korean Professional Engineers Association
    • /
    • v.34 no.1
    • /
    • pp.23-26
    • /
    • 2001
  • Seohae Grand Bridge is a part of the new West Coast Highway(353km) under construction, which connects Inchon and Mokpo. It is the longest bridge in Korea (7.31 km), and has 97 spans of 60m each precast segmental approach bridges, 2 main spans of 165m each free cantilever segmental bridge(500m), and 1 stay cable bridge of 990m In total length. During the seven year long construction period, many new construction technologies and methods were utilized for the first time in Korea, and gave invaluable opportunities to experience and master these in completing the project on time with safety and precision. I am proud of being a member of this project, and wish to express deep appreciations to those who participated in the project.

  • PDF

Seismic performance of Piers in Seohae Grand Bridge (서해대교 PSM교 교각의 내진성능)

  • 이재훈;손혁수;배성용;박찬민
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.4 no.3
    • /
    • pp.67-81
    • /
    • 2000
  • 서해대교는 국내에 교량구조물에 관한 내진설계가 도입되기 전 설계된 교량으로서 현재 내진설계 규준에 적합하지 않은 종방향철근 및 횡방향 철근이 겹침이음된 중공육각형 단면의 철근콘크리트 기둥으로 이미 시공이 완료된 상태이다. 최근, 지진에 대한 사회적 관심이 대두됨으로서 내진 설계 규준에 적합하지 않은 철근상세를 가지 서해대교 PSM교 교각의 내진성능이 의문시되었다. 따라서, 비내진 철근상세를 가진 서해대교 PSM교 교각의내진성능 평가를 위하여 교각의 축소모형 실험을 수행하였으며, 실험결과 종방향철근 겹침이음이 교각의 전체적인 내진거동에는 큰 영향을 미치지 않으며 기대 이상의 연성을 발휘할 수 있는 것으로 나타났다. 본 논문에서는 축소모형 실험결과에 의한 시험체의 파괴양상, 유효강성, 연성, 응답수 정계수 및 등가점성감쇠비를 분석하였으며, 아울러 가속도변위 응답스펙트럼을 이용하여 서해대교 PSM교 교각의 내진성능을 평가하였다.

  • PDF

Construction Method of Seohae Grand Bridge (서해대교 시공 공법 소개)

  • Yoon Tae Seob
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • autumn
    • /
    • pp.255-266
    • /
    • 2000
  • Since 1993, Seohae grand bridge has been continued construction for 7 years and will be completed late this year. The bridge is a part of west sea castal highway and consists of 3 types of bridge including precast segmental method, free cantilever method and cable stayed bridge. A cable stayed bridge is the core of this bridge and it consists of 5 span, symetrical cable-stayed bridge with a total length of 990 m. The main span between two H-shaped pylons extending approximately 180 M above massive foundation of a cable stayed bridge is 470 m long and an approach span of that is 260 m long respectively. The circular cofferdam with 16 ea of 25 m diameter flat type sheet pile had been applied to construct foundation. The slipform method had been applied for forming of con'c of two H-shaped pylons with 3 cross beams respectively which is varied horizontally and vertically. The deck has been erected with balanced cantilever method using movable derrick crane. The stay cables is a bundle of parallel individually protected, 7 wire high tensile strands. The strands is hot deep galvanized and sheathed with a tight high density polyethylene coating. A petroleum wax fills all the inter-wire voids. The bundle of strands to prevent from deterioration due to the ambient problem covered with high density polyethylene pipe. The Isotension method has been applied for the stressing of cable strands to ensure uniformity of force in all the strands of a syay and such works has been performed on the stay specially provided in the pylon.

  • PDF