DESIGN OF HIGH STRENGTH SPIRAL REINFORCEMENT IN CONCRETE COMPRESSION MEMBERS

摘要

Current provisions of the ACI 318 Code and AASHTO Design Specification limit the nominal yield stress of spiral reinforcement for compression members to 414 MPa (60 ksi). A procedure for the design of high strength spiral reinforcement for compression members is described. The procedure utilizes useable stress values, rather than nominal yield stress values, for spiral design. To evaluate the design procedure, concentric axial load tests were performed on six spirally reinforced concrete compression members with spiral reinforcement yield stress values ranging from 538 MPa (78 ksi) to 1345 MPa (195 ksi), and useable stress values ranging from 545 MPa (79 ksi) to 1131 MPa (164 ksi). It was found that, for the compression member geometries and material properties treated in this study, the proposed design procedure satisfactorily predicted the behavior of the compression members made from spirals with useable stress values up to 758 MPa (110 ksi).