Abstract
Four reinforced concrete columns with 400 mm (15.7 in) square cross sections were tested under axial compressive load and cyclic flexure to simulate severe seismic loading. The longitudinal reinforcement consisted of eight bars. The transverse reinforcement consisted of square perimeter hoops surrounding all longitudinal bars and cross ties between the intermediate longitudinal bars. The major variable of the study was the type of anchorage used for the hoops and cross ties. The anchorage details involved arrangements of perimeter hoops with 135° end hooks, cross ties with 90° and/or 180° end hooks, and cross ties and perimeter hooks with tension splices. Conclusions were reached with regard to the effectiveness of the tested anchorage details in columns designed for earthquake resistance.
Highlights
T y by Considerable efforts have been made in recent years to develop improved seismic design provisions for reinforced concrete columns in bridge substructures and building frames
The most important design consideration for ductility in the potential plastic hinge region of reinforced concrete columns is the provision of sufficient transverse reinforcement in the form of rectangular arrangements of hoops, with or without cross ties, or circular spirals or circular hoops, in order to confine the compressed concrete, to prevent buckling of the longitudinal bars, and to prevent shear failure
With 4 00 mm (15.7 in) square cross sections were tested under axial compressive load and cyclic flexure to simulate severe seismic loading
Summary
Considerable efforts have been made in recent years to develop improved seismic design provisions for reinforced concrete columns in bridge substructures and building frames. The San Fernando earthquake in Southern California in February 1971 caused extensive damage to a number of recently constructed reinforced concrete columns in bridges and buildings, mainly because of inadequate detailing of those structural members for ductility (see Fig. 1 ). The most important design consideration for ductility in the potential plastic hinge region of reinforced concrete columns is the provision of sufficient transverse reinforcement in the form of rectangular arrangements of hoops, with or without cross ties, or circular spirals or circular hoops, in order to confine the compressed concrete, to prevent buckling of the longitudinal bars, and to prevent shear failure. Seismic design codes normally specify design provisions for the quantity, spacing and anchorage of transverse reinforcement in the potential plastic hinge region of columns
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have