7. 4 however, we will treat only the hoop stress in the cylindrical section of the hull as given above. A different kind of load is imposed upon the hull by the necessity to dock relatively large containers of cargo to the spinning hull. There must be an impact load associated with this docking operation as well as a torsional load caused by matching the container rotation rate to that of the hull. These loads are absorbed primarily by the docking port which is discussed in Section VI.9.4. Finally, the double-hull configuration leads to stresses in the bulkheads separating compartments due to differential radial expansion of the inner and outer hulls. The relative magnitudes of various components of the static loading are investigated in Section VII.4. The dynamic loads that might be encountered arise from the fact that the hull structure may not realistically be considered a rigid body. It is expected that the hull might assume vibratory mode shapes in one or more of the following forms: bending, torsion, and bulging. These modes are discussed in greater detail in Appendix VII.B together with calculations to determine the relative degree of excitation of each mode. It must be emphasized that the analysis of dynamic loads was limited by lack of time and resources. For the purposes of stress analysis an alternating stress was assumed superimposed over the static mean stress level. The variation of this alternating stress , omax - omin' was assumed equal to 10% of the static stress level. VII.2.3: Construction and Spin-up: During the construction phase of the project, large prefabricated sections of the hull will be moved from the point of manufacture to an assembly point. Loads will be developed in the trusswork used in construction which will be proportional to the product of the section mass and a specified acceleration. Additional loads will be incurred as reaction forces are produced to keep the construction apparatus in position. As is proposed in Section VIII.7.4, large 20m x 20m pieces of the hull with a mass of 125.9 metric tons will be accelerated at lm/sec 2 . The resulting static load would then be 125,920 N. However, the construction trusses are very slender members and may not be
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