7 research outputs found

    고강도 재료가 사용된 철근콘크리트 요소의 면내 전단 거동

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    학위논문 (석사)-- 서울대학교 대학원 : 건설환경공학부, 2014. 2. 조재열.This thesis presents the results of twelve reinforced concrete elements subjected to shear and biaxial stresses. These elements were constructed by one-third scale of real nuclear power plant wall elements. And the load conditions were determined by considering earthquake and accidental inner pressure when the nuclear power plant is overheated. Elements were loaded until failure using University of Torontos Shell Element Tester. The concrete compressive strength, steel yield strength and reinforcement ratio of APR 1400 that is current model of nuclear power plant in Korea were used for reference element. And the high strength concrete, high yield strength steel and decreased reinforcement ratio were used for other elements to compare with the shear behavior of reference elements. On the other hand, in recent years, design codes have incorporated compression field theory for the design of reinforced concrete structures subjected to shear. Especially the Modified Compression Field Theory has become the basis of the shear provisions in CSA Standards, AASHTO LRFD, fib Model code and Eurocode 2. It is expected that ASME, ACI 318 and ACI 349 design codes that commonly used in the design of nuclear power plant structures will implement Modified Compression Field Theory based provisions in the near future. The ultimate load was accurately predicted with a mean test to predicted ratio of 1.03 and a coefficient of variation of 6.4 %. The shear strains at peak shear stress were also accurately predicted with a mean test to predicted ratio of 1.04 and a coefficient of variation of 13.5 %. The Modified Compression Field Theory also well predicted the cracked shear stiffness of elements. These results show the applicability of the Modified Compression Field Theory to shear design of nuclear power plant wall. And the new tension stiffening equation for large reinforced concrete elements is proposed based on the test results.Chapter 1 Introduction 1 1.1 General 1 1.2 Modified Compression Field Theory 4 1.3 Objective and Scope 9 Chapter 2 Experimental Program 10 2.1 Test Variables 10 2.2 Specimen Descriptions 16 2.3 Shell Element Tester 21 2.4 Instrumentation 24 Chapter 3 Experimental Results 30 3.1 N420A Series 32 3.2 N550B Series 41 3.3 N550A Series 50 3.4 H550B Series 58 3.5 H550A Series 66 Chapter 4 Observations and Analysis 74 4.1 Applicability of High-Strength Materials 74 4.2 Applicability of Modified Compression Field Theory 79 4.3 Modification of Tension Stiffening Equation 88 Chapter 5 Conclusion 124 References 125 Abstract 128Maste

    The Analysis of the Cognitive Level of Basic Job Skills of Specialized High School Based on NCS

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    Training needs analysis for the development of basic job skill curriculum in specialized high school

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