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D. RESULTS OF ANALYSIS <br />The structural capacity of the roof top structure was evaluated for the followingcriteria: <br />1. Main Member Capacity: The maximum member stress results for loadcombination 1 was compared with allowable stresses as defined by theAluminum Association in "Specifications for Aluminum Structures," FifthEdition. <br />2. Connection Capacity: The bolt stresses at critical field splice locations forload combinations 1 was compared with bolt capacities defined by the AISCCode, Ninth Edition. <br />3. Overturning Stability: The forces in the guys and hold down requirementswere determined for load combinations 2 and 3. <br />4. Foundations for Tower Base: Based on the maximum axial load results in thetowers for load combination 1, foundation recommendations for the towersare offered. <br />The results for each Ibad-combination"analyzed can be summarized as follows: <br />Load Combination 1:.SW+RTC+R+O (Gravity Effects) <br />The main member and connection capacities conform to Aluminum Associationand AISC Allowable Stress Design criteria, respectively. The flexural and shearresults for the roof top components are summarized in Appendix C. <br />The maximum axial force in the tower legs is 15,600 lbs. while the axial loadcapacity of the tower sections is 26,000 lbs. - It should be mentioned that the axialload capacity of a tower section that is not guyed at the top is only 2,170 lbs.Therefore; it can be .seen that the guy. supports contribute to the gravity. -loadcapacity as well as to stability against wind loads. <br />Based on a maximum axial load at each tower of 1 5,600 lbs. and an allowablebearing capacity of 1500 psf the towers should be supported on a rigid baseapproximately 4 ft. x 4 ft. in plan. A suggested base would be a mat built-up ofone layer of 12"xl 2" wood timbers running in one direction and one layer of3"x 1 2" white oak members running in the other direction. <br />10