Title |
Confinement Steel Amount for Ductility Demand of RC Bridge Columns under Seismic Loading
|
Keywords |
철근콘크리트 교각; 내진설계; 심부구속철근량; 소요연성도; 설계제안식; reinforced concrete bridge columns; seismic design; confinement steel amount; ductility demand; proposed design equation |
Abstract |
This paper is a part of a research program to develop a new design method for reinforced concrete bridge columns under seismic loading. The objectives of this paper are to investigate the relationship between ductility and confinement steel amount and to propose a design equation for reinforced concrete bridge columns. Computer program NARCC was used for parametric study, which was proved to provide good and conservative analytical result especially for deformation capacity and ductility factor compared with test result. A total of 7,200 reinforced concrete columns confined with spirals or perfect circular hoops were selected by combination of variables such as section diameter, aspect ratio, concrete compressive strength, yielding strength of longitudinal and confinement steel, longitudinal steel ratio, axial load ratio, and confinement steel ratio. Based on the parametric study a new design equation for confinement steel amount considering ductility demand was proposed, which can be used in the new seismic design method, i.e. ductility-based seismic design, for RC bridge columns.
|