Abstract: The authbr gives variatioaal principles of elastic-viscous damics is spectral resolving formula, it will be eatended to Laplace traasformetioa forte is this paper, mined variational principle of shell dynamics and variational principle of dynamics of dynamics of elastic-viscous-porous media are concerned,for the.later F., E. M. formulation is worked out.Variatioaal principles is Laplace transformation force have concise forms, for the sake of utilizing F, E. M. conveniently, it is necessary.to find out the values of preliminary time function at some instants, when values,of Laplace transformation at some points are known, but there are no efficient methods till now. In this paper, a aumerival method for finding discrete values of preliauaary function is presented, from numerical wzgmnles, we see such a method is efficient.By corubiaiag. both methods,stated above, variatioaal principles is Laplace transformatioa form and:numerical method,quite wide district of solid, dynamic problems can be solved by the aid of digital computers.