Abstract: Currently, the thermal stress analysis simulating the construction process of mass concrete structures primarily adopts the finite element method (FEM). But much computation is required and difficulties in mesh generation are encountered in conducting FEM analysis of complicated structures. For convenience in adaptive analysis and mesh division, the numerical manifold method (NMM) provides a new effective approach for the thermal stress analysis. The effects of the concrete creep should be generally considered in the thermal stress analysis as the concrete creep can reduce thermal stresses. The recursive formulae of the concrete creep widely used in FEM, which were derived based on the stresses at numerically integrated points of finite elements, are not suitable for NMM analysis due to the stresses of manifold elements are expressed in the polynomial form, especially in high-order NMM. According to the recursive formulae of concrete creep used in FEM, recursive formulae of concrete creep and formulae of corresponding equivalent loads suitable for NMM analysis are deduced. On the basis of the derived formulae, a program of high-order NMM for the thermal field and the thermal stress analysis is developed and verified by an example.

Key words:  NMM  , mass concrete structure  , recursive formulae of creep  , thermal stress  , simulation analysis