Static and Fatigue Tests on Precracked Rc Beams Strengthened With CFPR Sheets

Effect of the Cyclic Crack Opening-Closure during Epoxy-Curing Period of a CFRP Strengthening System Bonded on Concrete Substrate

“…This frequency was also applied during the second phase of fatigue of ES2 (see the fatigue test program of beam ES2 below). This higher value of frequency was adopted as it was previously used by several authors to study the behavior of RC beams strengthened with CFRP [25][26][27][28]. Considering that all cycled specimens were subjected to the same frequency of 4 Hz (except during first phase of fatigue test of ES2), it was assumed that comparison of specimen behavior between each other makes sense.…”

“…In other words, if an effect of positioning exists, it is expected to be less important than the one induced by cyclic loading. Indeed, it is recalled that the bonding performances of CFRP with concrete substrate is usually assessed from tests carried out on samples that are strengthened by bonding the CFRP on the concrete substrate located below: pull-out tests with CFRP bonded on the upper face of concrete slabs (see for example [29,30]), shear tests with CFRP bonded on the upper face of concrete blocks [31][32][33] and small beam test with CFRP bonded while the beam is upside down [20,28]. Moreover, the cyclic loading during CFRP installation was not expected to damage the CFRP/concrete bonded joint but rather to have a detrimental effect on the formation of the matrix of the CFRP material.…”