Professor F. W. Williams (M) (University of Wales Institute of Science and Technology): It is useful to note that Armstrong's notation enables the authors' method to be stated, much more concisely and simply, as an application of the familiar stiffness matrix method, as follows.
This paper deals with the various factors that affect the racking resistance of timber framed panels. The principal factors are the sheathing materials, the extent of vertical loading, the length of the panel, openings, holding down and the nail spacing. Other factors are generally of lesser importance. Test results relating to these factors are analysed, and a relationship is derived for each factor. The effects of outer claddings and inner linihgs are discussed very briefly. A simple design method for calculating the allowable racking resistance of panel assemblies is suggested. R.A. Robertson and D.R. Griffiths