METHOD FOR ANALYZING COMPLEX VISCOELASTIC STRUCTURES

The paper presents a method of analysis for structures composed by bea m members with different creep properties, whose structural configurat ions are repeatedly modified. A great deal of attention has been dedic ated to this problem since it occurs very frequently in practice. As i s known, the problem is governed by a coupled system of Volterra integ ral equations for each intermediate stage, and involves considerable d ifficulty in its calculus. The proposed method simplifies the mathemat ical formulation of the problem. Among other things; some advantages a re obtained by introducing a corollary of the theorem of virtual work, which has no particular advantages with respect to the usual elastic methods, but is very appropriate for use in the viscoelastic analysis of heterogeneous structures. By imposing compatibility conditions at t he delayed restraints, the general statement of the problem is present ed. Subsequently, by using the numerical step-by-step procedures of th e general method a rapid numerical algorithm, which must necessarily b e computer processed, is proposed. Finally, some numerical application s are carried out for three different types of structures.