CYCLIC BEHAVIOR OF STEEL-FIBER MORTAR OVERLAID CONCRETE BEAMS

A study was carried out to investigate the cyclic behavior of steel-fi ber cement-mortar overlaid concrete beams at various stress levels. Tw o different volume fractions of steel fibers were selected for the; pr esent study. The concrete-beam specimens used in this study were teste d simply supported with a point load at midspan. Two different types o f bonding conditions were studied. The deterioration in the flexural r igidify of the test specimens after being subjected to a predetermined number of load cycles was evaluated. The test specimens were subjecte d to 100,000 cycles of loading under a maximum load of 45, 55, and 65% of the ultimate static load. Static loading tests to failure after 10 0,000 cycles of applied load showed that some of the beams loaded up t o 65% of ultimate static failure strength failed by partial or complet e delamination of the overlay. The results of the experimental tests a re summarized and discussed in this paper.