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C. METHOD OF ANALYSIS (CONT.) <br />Primary Load Case 2: Gravity Loads - Roof Top Cover (RTC) <br />The weight of the canvas cover for the roof top structure is applied as uniformly <br />distributed loads to the apex members. The total weight of the 65 ft. x 45 ft. rooftop cover, applied in our analysis, is on the order of 550 lbs. <br />Primary Load Case 3: Gravity Loads - Riggers (R) <br />Roof live loads accounting for the weight of 200 lb. riggers were applied to theFEM model at the locations on the roof to give the maximum bending results.Roof live loads equivalent to six (6) riggers were applied to the 65 ft. x 45 ft. rooftop androof live loads equivalent to two (2) riggers were applied to each soundwing. The total live loads applied to the roof top and sound wings is 2000 lbs. <br />Primary Load Case 4: Gravity Loads - Operating Loads (0) <br />A maximum uniformly distributed operating load of 60,000 lbs. is to bd applied tothe 65 ft. x 45 ft. roof structure and sound wings during performances. This loadwill be distrib.uted..asz·a uniformly.distributed load ·.of.. 36,0004·lbs..I.·to·-the:-·Foof ·structur@ ahd 12,000-lbs. to *ach sodnd wing (8,000 lbs. to each· sound wingfront truss and 4000 lbs. to e@ch sound wing back truss). To account-for dynamiceffects, these loads are multiplied by an impact factor of 1.25, and a· unif.ormly.distributed load- 0 of. 75-,000 lbs?*is actually applied to the FEM model. <br />It should be mentioned that, although the roof and sound wing structure is ratedfor 60,000 lbs., the chain hoists lifting the roof are only capable of supporting40,000 lbs. (4000 lbs. or 2 tons per hoist). Therefore, the roof structure must besecurely attached to. the towers and sound wings before applying the maximumuniformly distributed operating load of 60,000 lbs. <br />Primary Load Cases 5 through 10: Wind Loads (WL) <br />ANSI/ASCE.-7.-95 wind··lo.adings for a_3-second gust.wind speed of 70 mph areapplied to the FEM model to determine the wind effects on the roof members, aswell as global wind overturning effects on the roof top structure. Design verticalwind pressures were determined using, "Table 6-6: Force coefficients forMonoslope Roofs over Open Buildings."Design lateral wind pressures weredetermined using, "Table 6-8: Force Coefficients for Solid Signs," and "Table 6-10: Force Coefficients for Trussed Towers." <br />·t i <br />7