P-model plate problems are described in this paper, and the structures
of their solutions are investigated in their dependence on the plate
thickness in the cases of clamped-in, soft clamped, hard simply suppor
ted, soft simply supported and free boundary conditions. By adopting s
ingular perturbation method, asymptotic expansions of the solutions wi
th respect to the plate thickness are obtained to arbitrarily high ord
er, assuming that the domain and the transverse load force are suffici
ently smooth. Rigorous bounds for the errors in the expansions are als
o given. In Part II, these results will be adopted to study the bounda
ry layer behaviour for the p-model plate problems.