Creep of thin shells in consideration of the anisotropic materials and the different behavior in tension and compression

Experimental investigations of creep of new engineering materials (flight alloys, cast irons, plastics, ceramics, composites etc.) show a different behavior in tension and compression. In the paper the formulation of a boundary value problem for the anisotropic creep of general shells of revolution under axisymmetric loading and in consideration of different behavior in tension and compression are given. The constitutive equations are in connection with some invariants of the stress tensor and tensors of anisotropy. The numerical solution of the problem is connected with the integration of a Cauchy problem and the simultaneous solution of the linearized boundary value problems, based on a discrete orthogonalisation method. A circular cylindrical shell with a clambed and a free end is discussed as example. The loading conditions - external pressure. There are investigations of isotropic and anisotropic material behavior (light alloys). It is shown the quality and quantity influence of the different behavior in tension and compression on creep of shells. (orig.)