탑다운 공법 적용을 위한 원형 콘크리트 충전강관(CFT) 기둥과 철근콘크리트 무량판 접합부 상세 개발

This paper summarizes full-scale test results on circular CFT (Concrete Filled Steel Tube) column to RC flat plate connections for Top-Down construction. In Top-Down construction, the column is first settled to the foundation. and then the slab is constructed simultaneously with excavation. Conventional wide flange (or H shape) columns welded with shear studs require larger predrilled holes which lead to cost increase. Furthermore, welded shear studs was are often damaged during construction. As a promising alternative, this paper presents a new top-down method which uses circular CFT column and bolt-jacketing/bearing plate details to connect the pre-settled column to RC flat plate. Test results showed that the proposed connection details can exhibit punching shear strength greater than those of RC flat plate.