Abstract
The flexural capacity of reinforced concrete structural elements can be increased by bonding
carbon fiber reinforced polymer (CFRP) plates to the tension surface creating a composite
structural element. Debonding of the CFRP plate from the concrete surface is the most likely
failure mechanism of the composite structural element. This research study compares the bond
strength between a multi-directional CFRP (MD-CFRP) plate and a unidirectional CFRP (UDCFRP)
plate to the concrete surface. A single shear pull off test is used to establish if additional
mechanical anchorage to epoxy bonded MD-CFRP or UD-CFRP plates to concrete would have
a combining capacity. The testing was conducted for the following three conditions (1) CFRP
plate epoxy bonded to a concrete block; (2) CFRP plate mechanically bonded to a concrete
block; (3) CFRP plate epoxy and mechanically bonded to a concrete block.