An experimental study of eccentrically loaded slender concrete masonry walls at full- and half-scale

Provisions in international design standards for the axial capacity of slender concrete masonry wall (CMW) behaviour have been noted to be inaccurate. These inaccuracies may be conservative in some cases and unconservative in others. A limitation to the improvement of these provisions is the lack of CMW experimental data. Logistical issues associated with the size of full-scale specimens limits the experimental data available in the literature. Scaled specimens can reduce logistical constraints, but the behaviour of CMWs at scale is not well understood. To improve the understanding of scaled CMWs in the literature, 12 CMWs (6 full-scale, 6 half-scale) were built and tested in eccentric axial compression inducing symmetric single curvature, with e = t /3 for all specimens. Walls were tested 1 year after construction. Failure loads and lateral load-deflection profiles are provided for all specimens. The experimental data yield several key observations: increased variation in f’ m at half-scale (up to 9.9 %), and at 1 year compared to 28 days (up to 9.3 %); increased variability (3.2 %) in mortar joint thickness at half-scale; and similar behaviour at scale for all types of tested walls when accounting for expected variation in f’ m . A simplified test rig, eliminating the bottom roller typically used in slender CMW testing, was used in the test. The simplified test rig was found to induce no membrane action in all walls with h / t = 20 and is recommended for slender CMW testing due to its increased constructability. • 12 concrete masonry walls tested in eccentric axial compression at full, half scale. • Walls tested at 1 year of age; failure loads, load-deflection data provided. • Increased COV in grout, prism strengths noted at half scale and 1 year • No scale effects at half scale for masonry walls in eccentric axial compression. • Simplified test rig recommended for walls with h/t ≥ 20.