[en] A three-dimensional finite element analysis computer program was developed. Two of the material models incorporated into the program allow independent specification of the shear moduli and in one of the models, one of the moduli can be specified as nonlinear (bilinear). The purpose was to implement a realistic model for cracked reinforced concrete into analyses of reinforced concrete containment vessels and to determine its effect on containment response. The nonlinear material model was derived from experimental results for reinforced concrete panels subjected to combined in-plane tension and shear. Various assignments of shear moduli were made around the circumference of the vessel in an effort to use the available experimental data in conditions under which it was obtained. The analytical model for the containment was subjected to static loads that are representative of horizontal seismic loading