IN-PLANE BEHAVIOR OF UNREINFORCED MASONRY (URM) WALLETTES WITH SELF-HEALING GEOPOLYMER MORTAR USING DIGITAL IMAGE CORRELATION (DIC)

Abstract

Geopolymer material is susceptible to cracking due to its inherent brittleness, which can compromise the service life of a structure. For that reason, the repair of these cracks is necessary and sometimes requires immediate attention. However, manually repairing the cracks takes a significant amount of time and resources. Hence, the self-healing of cracks is desirable to make maintenance and repair easier. This paper presents an experimental investigation of the in-plane behavior of unreinforced masonry wallettes with geopolymer and bacteria using digital image correlation (DIC). Moreover, it also aims to determine the strength contribution of the bacteria after pre-cracking the masonry wallette by 50% of the ultimate capacity. A two-dimensional (2D) Digital Image Correlation (DIC) technique was utilized in parallel with Linear Variable Differential Transformers (LVDT) to monitor the vertical deformation of the wallettes during testing and to capture the cracking of the unreinforced masonry wallette made of clay bricks. A percentage value difference of 17.09% was obtained from the vertical displacement of an unreinforced masonry wallette using the LVDT and DIC methods. Furthermore, it was demonstrated that incorporating bacteria with polypropylene fiber into an unreinforced brick wallette resulted in an ultimate shear stress of 2.77 MPa and a strength regain ratio of 225.39%. Thus, the experiment revealed that Digital Image Correlation (DIC) can be utilized as an alternate approach for evaluating the in-plane behavior of an unreinforced masonry wallette and that infusing bacteria and polypropylene fibers into a masonry wall can be a feasible alternative to strengthening the wall.