7. 5 considered perfectly rigid. Thus, they must be designed to sustain stresses resulting from the dynamic response of the truss to various concentrated impulsive loadings. It is recognized that the problems of dynamic overload may be severe and certainly merit further study. A dynamic analysis of the proposed trusswork structures to be used in the colony is, however, beyond the scope of this report. In the spin-up and pressurization phase of the project, special loads will be imposed upon the hull. Since the colony will be spun by torque-producing devices attached to the outer hull, the bulkheads connecting the inner hull to the outer hull will be subjected to a shear loading imposed by the rotational inertia of the inner hull. Additionally, the normal operational loads will be applied with increasing magnitude during the process of spin-up and pressurization. This variation in the loading condition imposes a variation in the radial expansions of the inner and outer hulls. The radial stresses in the bulkheads will then be dependent upon the instantaneous value of the difference of inner and outer radial ex?ansion, 6R 0 - 6Ri. VII.2.4: Damage-Induced Loads: There are several forms which damage might take, each producing a special loading distribution. A real possibility exists that one of the space ferries used to transport people and materials might crash into the docking port. In order to ensure that the energy transfer involved in such a collision would not catastrophically damage the hull, the docking port is designed to absorb impact energy by means of shock absorbers and a crushable honeycomb structure (see Section VI.9.4). Another form which damage might take involves the loss of structural integrity of either the outer hull, the inner hull, or the bulkheads. Loss of structural integrity is assumed here to mean the inability of a member to support the loads normally applied to it. The cause of such damage might be high energy fragments which penetrate a panel or the growth of initial cracks to critical length failing an entire panel. The damage scenario used in this report postulates the failure of a corner joint between four panels and the subsequent loss of all four panels. The situation is shown in
RkJQdWJsaXNoZXIy MTU5NjU0Mg==