This paper presents one approach for the analysis of snap behaviour of simply supported elastic shallowshells. Structure is discretized with the finite strip method. Displacement field is approximated withseries of products of polynomials and harmonic functions. Only geometric nonlinearity of von Karmantype is considered. Equilibrium equations are derived via principle of stationary value of total potentialenergy and solved with arc-length method. Total Lagrangian approach is used. Detailed analysis of oneshallow shell is performed. Obtained results are in good correspondence with the ones from the finiteelement method.