Effect of Reinforcement Spacing on the Behaviour of Out-Of-Plane Concrete Block Masonry Walls

Date of Award

Fall 2021

Publication Type


Degree Name



Civil and Environmental Engineering

First Advisor

S. Das

Second Advisor

N. Van Engelen

Third Advisor

R. Seth


Concrete masonry, Stack pattern




Stack pattern concrete masonry walls are commonly viewed as woefully insufficient load bearing walls compared to those constructed in running bond. For this reason, in Canada stack pattern construction is not permitted for load bearing walls. This research experiment was carried out to directly compare stack pattern construction to running bond and determine the differences in effective compression zone width. The experiments consisted of six partially grouted wall specimens, three of which were constructed in running bond and the other three in stack pattern. Three different rebar sizes and spacings were used to create equal effective reinforcement area with variable spacing. The walls were loaded axially and out-of-plane via four-point bending. There were 24 prisms tested along with these walls to determine the compressive resistance of the partially grouted walls. The test results found the stack pattern walls to be much more effective than they are commonly believed to be.