프리플렉스 보의 내력 및 변형특성에 관한 실험적 연구 ( Experimental Study on the Strength and Deformation characteristics of Preflex Beam )

A preflex beam is a type of concrete encased steel beam of which prestressing has been introduced in the lower flange concrete. To build up preflex beam, preflexion load are first applied to the steel beam, and secondly, while keeping the steel beam bent, the lower flange concrete is cast. Then, releasing the applied loads after the concrete hardened, the prestress is introduced into the concrete. This preflex beam has merits such as large flexural stiffness with smaller beam depth and low maintenance costs. Recently, in this merits, it has been demanded to apply the preflex beam to building structure of large span such as bowling center and gymnasium. In this paper, the strength and deformation characteristics of preflex beam are discussed through positive and negative bending experiments of preflex beam as a strength test.