Effect of Cyclic Loading on Punching Shear Strength of Slabs Strengthened with Carbon Fiber Polymer Sheets

In this paper, the effect ofcyclic loading on punching strength offlat slabs strengthened with carbonfiber reinforced polymer (cfrp) sheets is studied. experimental results of ten slab specimens undermonotonic and cyclic loading are analyzed. eight specimens were strengthened with cfrp sheets on thetensile face of the slabs and the two other specimens were kept un-strengthened as control specimens. thewidth of cfrp sheets varied in different specimens. after the tests, the punching shear strength of specimensunder cyclic loading was compared with those with monotonic loading. the comparison of results shows thatcyclic loading decreases the effect of cfrp sheets on punching shear strengthening. this decrease was morefor the specimens with a larger value of reinforcing steel ratio. therefore, it can be concluded that forspecimens with large reinforcing steel ratios, cyclic loading may completely eliminate the effect of cfrpsheets on shear strengthening of slabs.