Abstract: The generalized variational principles of isothermal quasi-static fluid foll-filled elastic solids are established by using Variational Integral Method. Then by introducing constraints, several kinds of variational principles are worked out, including five-field variable, four-field variable, three-field variable and two-field variable formulations. Some new variational principles are presented besides the principles noted in the previous works. Based on variational principles, finite element models can be set up.

Key words: fluid full-filled elastic solids, variational integral method, variational principles, generallied variational principles