The compressive strength of dry stacked masonry (smark masonry)

In a very labour intensive process, masonry structures are usually constructed by laying blocks on beds of mortar. Not only does this increase the construction time but the mortar provides a failure mechanism that doesn’t allow structural masonry to reach its full potential. It was thought to a large step forward for the masonry industry if the mortar could be eliminated from the system. Dry stacked masonry eliminates the mortar and a company that has such a system is a Brisbane based company called Smart Masonry. They created a unique system that uses interlocking blocks that held together with a plastic key driven into a dovetail recess in the webs of the perpends joints. The blocks also have unique shaped stepped profile that allows them to be easily stacked. The purpose of this thesis is to investigate the compressive capacity of this system with three different scenarios. They are the effect of: different grout strengths, vertically unrestrained reinforcement and poor compaction on the compressive capacity of this dry stacked masonry system. The current Australian Masonry Structures Code (AS3700) only has provision on conventional masonry. Our task was to report on any differences between the code and the results obtained from testing the Smart Masonry system. One hundred, 4 block high grouted piers were tested along with twenty individual blocks and ten, 4 block high ungrouted piers. From the results it was concluded that the current masonry code provide an underestimation of the compressive strength of this dry stacked system. A new formula was proposed to be included into the Australian Masonry Structures Code for this dry stacked system. It was also found that poor compaction leads to a significant drop in compressive capacity, so the current Smart Masonry guideline that all masonry construction be pencil vibrated should remain in place.