Assessing the impact of corner rounding and geogrid orientation on the structural response of externally confined masonry columns

Abstract

This paper presents an experimental evidence on the integrity of masonry columns externally wrapped with biaxial geogrid embedded in cementitious mortar. The specimens in research was grouped into two sets. First eighteen specimens compares the performance of columns confined with geogrid versus CFRP. While the next eighteen specimens investigates the effect of geogrid orientation on confinement. These comparative study are applied on two sets of columns: one with sharp cornered square columns and another with rounded square columns with 20 mm corner radius. A total of thirty six columns were tested. The columns measured 230 mm in width, 230 mm in depth and 760 mm in height. The failure mode, peak load, load displacement curve and strain energy are compared and discussed. The test results revealed that geogrid confinement improves both load carrying capacity, ductility and energy absorption capacity of masonry columns relative to CFRP confined and unconfined masonry condition. Experimental study on orientation angle of geogrid ribs revealed its impact on load capacity, energy absorption and ductility. Analytical models available in various literatures were used to predict the ultimate stress of masonry column. These were then compared to predict the reliability of various models for geogrid confinement.