NON-CONTACT MEASURING TECHNIQUES TO CHARACTERIZE DEFORMATION ON FRP UWRAP ANCHORS

摘要

Frp Uwraps have been successfully used for shear strengthening of concrete structures; by contrast, few studies have focused on the use of the Uwrap as an anchorage system for FRP flexure strengthening. This study focuses on exploring the limitations and advantages of using non-contact measuring techniques, such as digital image correlation (DIC) and thermography, to characterize the deformation of FRP Uwrap anchors. Digital and thermo images were used to evaluate the slip profiles and debonding propagation of FRP Uwrap anchors on a pull-out test configuration. Results indicated that the geometry of the Uwrap plays an important factor in controlling the delay or arrest of the debonding propagation of the externally bonded FRP sheet. The DIC technique was capable to accurately measure slip along the bonded FRP sheet whereas the thermography technique was successful at capturing the debonding propagation (in two directions), as well as the locations of stress concentrations and fractured areas.