Stone cantilever stairs are constructed in two basic forms, either with plain or rebated treads. The body of work available is generally confined to the examination of plain treads, yet the majority of stairs in existence are of the rebated type. This paper outlines guidelines for inspection of cantilever stairs and a method of analysis that predicts the behaviour of a flight of rebated treads under a variety of loading conditions. The theoretical analysis and model testing provide formulae for calculation of torsion, vertical and horizontal reactions, tread rotation, displacements and shear stresses.
Philip Little, BEng
Barrett Mahony Consulting Engineers
Michael Hough, BSc (Eng), Dip Struct Eng, MSc, CEng, MIEI, MIStructE
Barrett Mahony Consulting Engineers
Edward Mullarkey, BE, MSc, MIEI
Lecturer in Structural Engineering at Dublin Institute of Technology