7.37 apparent gravity to be felt throughout each building level and the maximum deflection sets a limit on the "springyness" of the floors. For an efficient transfer of loads from the buildings to the hull, it is best to place the major building supports over the hull bulkheads. These bulkheads are 20.94m apart (see Figure 7.12) in the circumferential direction and 22m apart in the longitudinal direction. In Appendix VII.G, a detailed analysis of an example interior structure is given. The floor is divided into SxS meter panels consisting of twenty-five lm x lm plates which are 3 cm thick, supported by minor stiffeners 3 cm x 12 cm in cross section. The floor and walls of the buildings are similar to the bulkheads in the hull design. The center deflection for the maximum design load of 5723 N/m 2 is 0.75 cm, which is larger than initially planned but more convenient from a manufacturing point of view. Since all the plates used in the building are identical to the bulkhead plates, the manufacture of panel sections is greatly simplified. The 3 cm wall and floor thickness allows the building to act as safety chamber in the event of a pressure failure in the colony. The building can withstand the total atmospheric load without yielding, which may be necessary in an emergency. The floors are supported every Sm by columns 12 cm x 12 cm in cross section. These are designed for maximum load on every floor plus the weight of each floor for the ground floor columns. The upper columns can be of proportionately smaller dimensions or they can all be the same for manufacturing simplicity. More sophisticated structural shapes might reduce the mass of the building described, but the analysis necessary to optimize building design is beyond the scope of the present report. VII.4.6.2: The Window: A 40m diameter window in one of the endcaps allows sunlight to enter the colony. For the purposes of analysis, the window is assumed to be fabricated from 97% silica glass with the following properties: Young's modulus E = 6.88xlo 10 N/m 2 Compressive yield stress= 6.895xlo 8 N/m 2
RkJQdWJsaXNoZXIy MTU5NjU0Mg==