Failure analysis and damage detection of partially grouted masonry walls by enhancing deformation measurement using DIC

Abstract

This study focuses on the deformability and damaging of ungrouted and fully grouted masonry assemblages and a full-scale partially grouted (PG) reinforced masonry wall made of concrete masonry units (CMU). Traditional point-to-point method using strain gages and full-field measurement technique using digital image correlation (DIC) were implemented to investigate the damage and deformability of specimens. All the specimens were constructed in compliance with the provisions of the Masonry Standards Joint Committee (MSJC, 2013) [37] and tested under displacement controlled loading. The DIC method was used to determine non-uniform strain contours on the masonry assemblages. The method was verified by comparing the strains along the selected directions with traditional strain-gage based displacement transducer (TML model) measurements. After verifying the method, it was used to investigate the state of damage and deformability of the wall. It was concluded that full-field measurements using DIC is promising especially when the test specimens experience inelastic deformation and extensive damage. Quantitative mapping of deformation field until the wall capacity is reached was only possible by using DIC. In addition to monitoring the strains across the gage length, the DIC method provided a full-field quantitative strain map of the test specimens to wall capacity and revealed strain hot-spots associated with the maximum strain at crack locations. Characterizing the deformation mechanism and cracking of the PG reinforced masonry wall was performed by determining strain distribution and recognition of cracks corresponding to the wall capacity and strains in higher than 0.3%.