• International Journal of Concrete Structures and Materials
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• 제11권1호
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• pp.161-169
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• 2017

Flat slab systems are vastly used in multi-story buildings because of their savings in story height and construction time, as well as for their flexibility in architectural remodeling. However, they frequently suffer brittle punching-shear failure around columns, especially when subjected to lateral loads. Therefore, seismic codes labeled flat slabs as non-ductile systems. This research goal is investigating some construction alternatives to enhance flat slab ductility and deformability. The alternatives are: adding different types of punching-shear reinforcement, using discreet fibers in concrete mixes, and increasing thickness of slab around columns. The experimental study included preparation and testing of seven half-scale interior slab-column connections up to failure. The first specimen is considered a reference, the second two specimens made of concrete mixes with different volumetric ratios of polymer fibers. Another three specimens reinforced with different types of punching-shear reinforcement, and the last specimen constructed with drop panel of inverted pyramidal shape. It is found that using the inverted pyramid-shape drop panel of specimen, increases the punching-shear capacity, and the initial and the post-cracking stiffnesses. The initial elastic stiffnesses are different for all specimens especially for the slab with closed stirrups where it is experienced the highest initial stiffness compared to the reference slab.

• 한국건축시공학회지
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• 제13권5호
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• pp.482-490
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• 2013

무량판 슬래브 구조는 시공의 단순함과 낮은 층고, 그리고 다양한 평면구성의 용이함으로 인하여 구조적으로 효과적이나 슬래브-기둥 접합부가 중력하중에 의한 펀칭전단파괴와 횡하중의 불균형모멘트에 의한 편심전단파괴에 취약한 단점이 있다. 이러한 무량판 슬래브의 취약점을 방지하기 위하여 많은 보강공법들이 개발되었으나, 보강공법들은 구조적 성능과 경제성, 그리고 시공성을 모두 만족시키기지는 못하고 있다. 이 논문에서는 래티스를 이용한 무량판 구조의 슬래브-기둥 접합부 보강공법을 제시하였다. 주기하중 실험을 통하여 래티스 보강공법의 구조적 성능을 증명하였으며 같은 구조설계 조건에 대하여 스터럽과 스터드레일, 그리고 래티스를 이용한 공법을 적용해 봄으로써 경제성을 입증하였다.