Compressive strength of dry-stacked concrete masonry unit assemblies

Dry-stacked masonry construction consists of individual units stacked directly without mortar at the bed and head joints. Although dry-stacked construction offers many benefits including speed of construction and minimal need for skilled labor, its use has been limited by lack of technical information. This paper presents the results of an experimental program investigating the compressive strength of dry-stacked assemblies built from nonproprietary standard concrete masonry units. The program included 124 tests of dry-stacked prisms; variables in the program included compressive strength of the units and treatment of the interface. Roughness of the interface was found to have significant effect on the load-displacement behavior and ultimate capacity of dry-stacked assemblies. Based on the experimental results, a unit strength method is presented for qualifying dry-stacked systems.