Different truss types: long-term creep in wooden bridges. A comparative study of their efficiency

Since mid-nineteenth century iron was widely introduced into wooden bridge truss types. A long-term creep evaluation, based on linear elastic model, is here presented in order to compare the effects of dead load in six different kinds of trusses in which iron is used in different truss members. The structural efficiency of the different truss forms has been evaluated in terms of initial elastic deflection and time needed to viscous deformation induced by creep so as to double the initial elastic deflection.