ABSTRACT
The types of joints actually used in steel trusses, e.g. Figure 8.17 and 8.18, will not, of course provide the 'perfectly pinned connections' usually assumed when determining the distribution of internal member forces. However, the triangulated nature of the framing will mean that the principal method of resisting the external loads will be by the development of a set of tensile and compressive member forces; bending effects will usually be of much less significance. Thus, with the exception of major structures, e.g. very long span roof trusses several metres deep of the sort used for the roof of the turbine hall in a power station, it is customary to design trusses and lattice girders of the type shown in Figure 10.2 as if they were pin-jointed. To assist with this, Cl. 4.10 of BS 5950: Part 1 provides a set of simplified design rules.
