Ultimate Strength of Reinforced Concrete Grid and Slab Bridges

A METHOD BASED ON PLATIC THEORY AND INCLUDING TORSIONAL RESISTANCE IS DESCRIBED FOR ESTIMATING THE ULTIMATE LOAD OF MEDIUM-SPAN REINFORCED CONCRETE GRID AND SLAB BRIDGES. FOUR 15-FT SPAN BRIDGES WERE TESTED TO FAILURE. THE RESULTS ARE COMPARED WITH THEORETICAL VALUES BASED ON BOTH ELASTIC AND PLASTIC THEORIES. THE METHOD BASED ON PLATIC THEORY GIVES A REASONABLY GOOD ESTIMATE OF THE ULTIMATE LOAD OF THE STRUCTURE. A PROCEDURE IS DESCRIBED FOR MINIMUM-WEIGHT DESIGN OF SUCH STRUCTURES ON THE BASIS OF PLASTIC THEORY AND LINEAR PROGRAMMING. /RRL/A/