Numerical results of simplified dynamic analyses on large imperfect space structures

Abstract Large space structures, with eigenfrequencies in the order of 10 −3 –10 −4 Hz undergo dynamic excitations which can be periodic (e.g. at the orbiting frequency) or shock-like, as sudden load application (crossing the Earth's shadow), and e.g. control system thruster pulses. The calculated dynamic response can essentially deviate from that obtained by linear analyses. Indeed the overall eigenfrequency of a truss-like structure can decrease by some orders of magnitude due to the inevitable imperfection of the struts, and a strong non-linearity occurs for larger vibration amplitudes. Slenderness ratios