*PN* 95/20 TI eng: Numerical methods versus asymptotic expansion for torsion of hollow elastic beams dt: Vergleich einer numerischen und einer analytischen L"osung f"ur die Torsion von elastischen Hohlprofilen AU Frischmuth, Kurt; H"anler, Michael; dell'Isola Francesco SO Preprint 95/20, ISSN 0948-1028 LA englisch AB We consider the torsion problem for a hollow elastic beam. In a series of papers dell'Isola et al.(1994, \cite{iso2,iso3}) a uniform method for the derivation of classical formulas for the torsional rigidity by Bredt, Prandtl and Vlasov was derived using an asymptotic expansion. We show that this expansion yields useful approximations for torsional rigidity if properly applied. Note that it does not converge in general. For the evaluation we use a numerical solution obtained by a Finite Difference Method. Finally, we examine the results of both methods for two example domains. CC 35R30, 65N30 UT elliptic boundary value problems, torsion problems, asymptotic expansions