Estimation of Mortar Compressive Strength Based on Specimens Extracted from Masonry Bed Joints

摘要

The article presents the results of the Double Punch Test (DPT) con ducted on cement-lime mortar. The tested specimens have dimensions of 5 cm x 5 cmwith a thickness of 12 mmandwereobtainedfrombedjointsofclay brick prisms prepared in the laboratory. For DPT purposes, 20 mm diameter steel punches were used. The reference mortar compressive strength was measured on standard specimens (4 cm x 4 cm x 16 cm), and the stress-strain relation was measured on cylinders (5 cm x 10 cm). Based on the reference compressive strength and DPT results, the correlation factor was established. The effect of the capping on the DPT strength was also measured and analyzed. Moreover, an individual FEM model was built and calibrated to simulate the DPT specimen failure mode and load-displacement behaviour. The results of the numerical simulations were compared to laboratory tests.