MAXIMUM USABLE CONCRETE STRENGTH LEVELS OF BRIDGE I-GIRDERS

摘要

Based on a parametric study of 700 simple and two-span example-bridges built with pretensioned NU and Bulb-Tee I-girders, the following observations are made: (1) Working stress design procedure does not control design when concrete strength reaches a certain level. (2) If inaximum shear reinforcement limit is expressed as a fraction of concrete strength, f_c', as the case in AASHTO LRFD Specifications, then the required shear reinforcement limit is inversely proportional to concrete strength. (3) It is possible to use strength design procedure alone for the design of HSC girders. (4) Maximum usable concrete strength levels are depended upon the prestressing force introduced.