LOAD-DEFLECTION CHARACTERISTICS OF REINFORCED CONCRETE COLUMNS UNDER STATIC ALTERNATING CYCLIC LOADS

The objects of the study were columns of reinforced concrete viaducts used in large numbers for railway and urban transportation structures. The influences of variable factors such as longitudinal reinforcement ratio, hoop ratio, and axial load on behaviors of members such as limit states of crack occurrence, yielding and ultimate state of member, ductility, and load-deflection characteristics under static alternating cyclic loads were experimentally investigated.As a result, it was concluded that the load-deflection loop can be modelled as a maximum-point-directed type without slipping, that among various variable factors the influence of longitudinal reinforcement ratio is extremely great, and that plastic hinge length and longitudinal crack formation are determined by the combination of the quantities of longitudinal reinforcement and hoop reinforcement.