Author: Jones, Royston;Baker, Alan Robert
N/A
Standard: £10 + VATMembers/Subscribers: Free
Members/Subscribers, log in to access
Jones, Royston;Baker, Alan Robert
The Structural Engineer, Volume 39, Issue 7, 1961
The critical load of a plane frame is that at which the resistance offered by the frame to any random disturbance is nil. For this state the stiffness matrix corresponding to all possible disturbances is singular. The elements of this matrix are quantities used in the moment distribution methods pieviously proposedthe moment distribution methods pieviously proposed and for most loads, not close to the critical load, the stability, or otherwise, of the frame is determined by inspection without performing the moment distribution. For loads near the critical load the problem is transformed into the calculation of the largest latent root of an allied matrix. This calculation is simpler than moment distribution. S. J. McMinn
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