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� • <br /> 2.0 CODES AND LOADING The existing structure is considered to have adequate strength for the proposed <br /> loading if the existing structural members which will be used to support the <br /> The existing structure was analyzed according to the following: proposed platform are structuratly adequate per the current code criteria or the <br /> additions and alteretions to the existing structure do not increase the load in any <br /> • ASCE 7-05,as referenced in the 2007 Minnesota Building Code and the structural element by more than 5%or the lateral force in any structural element <br /> 2006 International Building Code,with the following loading parameters. by more than 10%. <br /> o Design 3-Second wind gust speed in Hennepin County, MN is 90 <br /> mph. 4.0 CALCULATIONS AND OUTPUT <br /> o Recommended ice load is 3/4" radial ice for the entire structure <br /> concurrent with 50 mph wind speed. Calculations and Software output for this analysis are provided in Appendix A of <br /> o Exposure Category C this report. <br /> o Occupancy Category IV; I„=1.15, IE=1.5,I,=1.25 <br /> • AISC Steel Construction Manual, 13`"Ed. 5.0 CONCWSION <br /> The following load combination was used to compare loads on the water tank. The existing and proposed antenna mounts and handrail members are found to <br /> The numbers in parenthesis denote ASCE 7-OS equation numbers. have adequate capacity for the proposed antenna loading. At the worst case, <br /> the handrail members are stressed to 74.2%of their respective capacities. <br /> D+ (W or 0.7E) (2.4.1.6) <br /> Please reference the latest construction drawings by Velocitel for details of the <br /> The following load combinations were used to analyze the existing handrail proposed pipe mounts. <br /> members.The numbers in parenthesis denote ASCE 7-OS equation numbers. <br /> The existing water tank is found to have adequate capacity for the proposed <br /> 1.2D+ 1.6W+ O.SL(2.3.2.4) antennas. The seismic loads, which control the design of the water tank, <br /> 1.2D+Wi +Di + O.SL(2.3.4.2) imparted on the water tank by the existing and proposed antennas and other <br /> appurtenances are less than 5% of the total loads on the tank itself, and thus no <br /> 3.0 ASSUMPTIONS,ANALYSIS CRITERIA and METHOD further overall analysis of the tank structure is required. <br /> The following design values are assumed for the existing catwalk handrail: Therefore, the proposed additions and alterations can be implemented as <br /> intended,with the conditions outlined in this report. <br /> - All steel pipe members are ASTM A53 with a yield stress of 35 ksi. <br /> - All other steel members are ASTM A36 with a yield stress of 36 ksi. <br /> The existing handrail structure was modeled with RISA-3D, a general-purpose 3- <br /> dimensional analysis and design program. This program has been devetoped to <br /> make the definition, solution and modification of 3D structural models, utilizing <br /> finite element solutions. <br /> Ice loads have been calculated for each existing and proposed appurtenance; <br /> however, it is assumed that the ice and wind on ice loads cases will not control <br /> over wind or seismic load cases for the design of the tank and for comparing <br /> loads. <br /> A single 200 Ib point live load is applied to the handrail per ASCE 7-OS Section <br /> 4.4.1. <br /> Velocitel Inc. Velodtel Inc. <br /> ♦570 Cobmal Pack llnve,Suite 307�Roswell,GA 30075�(770)lrli-59W ofhce�(7'O)G-15S9�3 Ea� •570 Colonial Pack Dm�e,Sutte 307�Roswell,GA 30075�(770)GS>-5900 office�(770)G�i5S943 faz <br /> 3 4 <br />