Test data on the influence of panel size and the effect of steel platen restraint on the irreversible moisture expansion of Fletton clay brickwork are reported. Three sizes of single-leaf panel were monitored for movement as well as unbonded bricks and mortar prism samples. Measurements were taken for 612 days.
All the brickwork panels expanded both horizontally and vertically. After 612 days the ratio of brickwork to unbonded brick expansion in the vertical direction ranged from 1.6 to 3.8, indicating that some form of enlarged expansion was occurring in the panels. The equivalent ratios in the horizontal direction were less than one, however. Vertical moisture movement was found to be influenced by the stresses arising from the self-weight of the brickwork and the weight of a steel platen on the top of the panel.