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v <br /> _. .. <br /> .7 1, a.. .. ... ..._....._ .:,::.....� ... :�t::::: .. . ........... ... .. . .... .. .. . <br /> October 8, 1997 <br /> Scott Ballance <br /> Bechtel <br /> '• US West Wireless Project <br /> 426 North Fairview, Room 101 <br /> St. Paul, MN 55104 <br /> RE: Millerbernd Mfg. Co. Antenna Monopole Structural Integrity <br /> The Millerbernd Mfg. Co. monopoles used by US West for this project meets or exceeds the <br /> requirements of EIA/TIA 222 "Structural Standards for Steel Antenna Towers an i Antenna <br /> Supporting Structures" specification. This is the recognized specification for these types of <br /> c towers. When designing the structure, wind&ice loading along with the number, size,height <br /> and style of mounting ofthe antennas are taken into account to determine the size of the <br /> structure required. The structure will have an approximate safety factor of 1.5, or in other <br /> words,will be 1.5 times stronger than it needs to be. The monopole has been designed to <br /> withstand at least 100 MPH with a 1/2" thick coating of ice on the monopole and antennas. <br /> Millerbern.d Mfg. Co. only uses American-Made carbon steel(ASTM A572 or A607)which has <br /> a 50,000 PSI min yield. All our steel is ordered with mill certifications to verify integrity of the <br /> material The mill certifications are kept on file, should a copy be required at some future date . <br /> Only AWS-D1.1 "Structural Welding Code" qualified personnel will be used during the welding <br /> of the structure. Weld inspections will be performed by SNT-TC-lA qualified No -D <br /> estructive <br /> Test Personnel to verify the soundness of the welds. <br /> With the pole designed and manufactured in accordance with the above criteria, Millerbernd <br /> Mfg. Co. cert&es that the monopole will not collapse. <br /> Millerbemd Mfg. Co. has been in business since 1933 and manufacturing monopoles since 1948. <br /> Since then, thousands of monopoles have been built which are very similar to this type of <br /> structure without a single one collapsing. Millerbemd has been building antenna monopoles <br /> since 1990. In that time, 40 plus antenna monopoles-have been built anclalso without any <br /> collapsing. <br /> If you have any questions or concerns,please call me at(320)485-2111. <br /> Respectfully submitted I hereb y certify that this p Ian, sp ecificatio n <br /> , <br /> � 1��� —•�j or report was prepared by me or under my <br /> f Y�-J7S direct sup ervision and that I am a duly <br /> Wade Linnertz. P.E. Registered Professional Engineer under the <br /> ChisfEngineer laws of a State Minne ota. <br /> Date I° 8 47 Registration No. 24741 <br /> MILLERBERND MANUFACTURING COMPANY* P.O. BOX 98 • MNSTED, MINNESOTA 55395 <br /> PHONE(320)485-2111 a FAX(320) 485-4420 <br />