I. Kaljevic et al., TREATMENT OF INITIAL DEFORMATIONS IN THE INTEGRATED FORCE METHOD, Computer methods in applied mechanics and engineering, 140(3-4), 1997, pp. 281-289
A new force finite element formulation, termed the Integrated Force Me
thod, has been developed in recent years for the structural analysis.
In the Integrated Force Method all independent forces are treated as u
nknown variables which are calculated by simultaneously imposing the f
orce equilibrium and strain compatibility. The Integrated Force Method
is extended in this study for the treatment of initial strains. Initi
al strains are incorporated into compatibility conditions through the
vector of initial deformations. A general expression for the vector of
initial deformations is derived by discretizing the expression for th
e complementary potential energy of the structure. Two special cases o
f initial strains are analyzed in detail: (i) thermal strains and (ii)
support settlements. The vector of initial deformations due to therma
l loadings is derived by introducing expressions for thermal strains i
nto the general expression, and that due to support settlements is der
ived directly by equating the work done by external and internal force
s, respectively. Two example problems with available analytical soluti
ons are solved using the present developments. A good agreement of res
ults with analytical solutions is observed.