R. E. HOBBS* and K. J. EJSKJAER** *Imperial College **Tileman & Co. Ltd.


The largest stresses in sectional flue linings in brickwork are normally the bending stresses caused by temperature gradients through the lining often causing lining failure by vertical tensile cracks. The paper describes the development of novel units to increase the tensile strength of brickwork in bending about a vertical axis. The basic unit is a castellated plain brick, developed and refined experimentally and compared in wallette tests with plain brickwork and tongue-and-groove brick wallettes. The interlocking units are a significant advance in the design of thermally loaded brickwork. The results may have implications for other out-of-plane bending situations.