수직재 변형을 고려한 재사용 시스템 동바리의 구조 안전성 분석 = Structural Safety Analyses for Reused System Support Considering Deformation of Vertical Components

다국어 초록 (Multilingual Abstract)

System supports with recycled temporary resources are widely used in construction sites, and the use of deformed or damaged materials are increasing without knowing manufactured year or proper evaluation on the change of product strength. The reuse of unverified temporary resources has a potential risk such as collapse of system supports during the construction. In this thesis, therefore, a structural safety of system supports where damaged temporary resources are reused are analyzed. In addition, a guideline for reuse of temporary resources is proposed to secure structural safety based on the analysis results.
To analyze structural safety of system supports with reused temporary resources, a field survey is first conducted to investigate the problems of system supports which can be caused by reused materials. Using the reduction rate of the external diameter of reused vertical members, the member force is calculated with a commercial finite element analysis program for system supports having damaged materials. Then, the structural safety is analyzed by estimating combined stress ratio of system supports.
For a target system support designed to typical stress level (91% level of the allowable combined stress ratio), the vertical members in a lower center showing the most vulnerable are assumed as damaged components. The calculation results of the combined stress ratio according to various external diameter reduction rates show that the structural safety is verified up to the external reduction rate of 6% which shows a combined stress ration of 0.993. Therefore, the target system support can be applied without a revaluation up to the external reduction rate of 6%.
In addition, the case assuming the lower vertical member with less combined stress ratio(82% level of allowed combined stress ratio) as damaged member is investigated. The allowed combined stress ratio exceeds from the external diameter reduction rate of 12% but can be applied up to 10% of the external diameter reduction rate. However, the location of damaged member should be taken into account from the analysis in a design stage to comply with the performance criteria.

목차 (Table of Contents)

• Ⅰ. 서 론 1
• 1. 연구 목적 2
• 2. 연구 동향 3
• 3. 연구 방법 6
• 4. 연구 범위 및 제한사항 7
• Ⅱ. 이론적 배경 8
• 1. 시스템 동바리 구성 및 특징 8
• 2. 재사용 가설재 검정제도 이론적 고찰 15
• 3. 압축부재 좌굴 이론 23
• Ⅲ. 시스템 동바리 실태 분석 26
• 1. 현장조사 개요 26
• 2. 조사 결과 및 문제점 분석 28
• Ⅳ. 재사용 시스템 동바리 안전성 검토 39
• 1. 대상 시스템 동바리와 해석 모델 40
• 2. 대상 동바리 시스템의 안전성 분석 46
• 3. 단면 손상에 따른 안전성 분석 55
• Ⅴ. 결 론 65
• 참고문헌 67