나선철근 기둥과 띠철근 기둥: 설계상 무엇이 다른가

1구속 효과가 다릅니다

연속된 나선철근은 기둥 전체 길이에 걸쳐 코어 콘크리트를 고르게 감싸므로, 간격을 두고 배치한 띠철근보다 구속 효과가 좋습니다. 코어 콘크리트가 높은 압축 변형률에서도 강도를 유지하여 기둥의 파괴가 덜 갑작스럽습니다.

2기준의 처리 방식

나선철근 기둥은 거동이 더 연성적이므로, 기준은 압축지배 단면에 더 높은 강도감소계수를 주고 축력 상한도 더 높게 정합니다. 나선철근 기둥은 각각 0.75와 0.85배, 띠철근 기둥은 0.65와 0.80배입니다 [4, 5].

3설계에 미치는 영향

축력이 큰 기둥에서는 이 두 가지 차이가 설계강도에 직접 반영됩니다. 같은 단면에 나선철근을 쓰면 P–M 곡선의 상단부가 뚜렷하게 올라갑니다.

4StructFlow에서 전환하여 비교하기

참고문헌

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