The Determination of the Critical Loads of Plane Frames

Connexions employing high strength bolts have been shown to have many advantages oer riveted connexions but there are a number of aspects relating to the use of these bolts that remain imperfectly understood. One of these is the establishment of a satisfactory method of tightening. The requirements are (i) an accurately induced pre-load in the bolt, (ii) simplicity, both in tightening and in checking, and (iii) an adequate factor of safety against bolt failure resulting from over-tightening. Professor Royston Jones and Alan Robert Baker

In view of the recent interest in lightweight fire protection to steelwork, the writer would like to put forward for consideration some thoughts on designing steelwork especially for storage or other structures where risks are high.

A rectangular slab of constant thickness is considered which is simply supported along two edges and which has identical bcams, integral with the slab, along the other two cdges. Under conditions of transverse loading applied to both the slab and the beams, series solutions are obtained for (i) the transverse deflexion and (ii) the stress-function which describes forces in the plane of the slab. Appropriate conditions of symmetry, of simple-support on two edges and of equilibrium and strain-ccmpatibility at the slab-beam junctions are utilised to determine the constants in these series solutions. Torsional stiffness of the beams is taken into account. D. N. de G. Allen and R. T. Severn