Correspondence ARTISAN ENGINEERING, LLC - ei'ZYa2
— • • 325 West 13 Avenue
•
Eugene, 'Oregon 97401 -3402
Phone: 541- 338 -9488 Fax 541-338-9483
www:artisanengineering.00m �� V ED
•
May 12, 2005 NAY
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Mr. David Lyman CfTY �F r�
Gazley -Plowman n Architects �UIL DII�/G -4V/s/ N
2701 NW Vaughn, Suite 764
Portland, OR 97210
Re: Structural Review of Previous Analysis for 80-ft Verizon Monopole at 12955 SW Pacific Highway,
Tigard — Site: PL -77 Tigard (Prey. Cingular PT326-04) — Compliance with current IBC
Dear David:
Artisan Engineering, LLC has completed a review of the documents that you provided us for the 80-
ft Verizon Monopole at 12955 SW Pacific Highway in Tigard. The purpose of the review was to
determine if the results of the latest structural analysis are still valid and meet the current IBC for the
current proposed Cingular antenna configuration. We performed this review per your request earlier
this week.
The current IBC references the current TIA/EIA for the design criteria for monopoles, towers and
other antenna supporting structures. This monopole was designed to the TIA/EIA 222 -F which is -
(" the current design standard.
i According to the documents that you sent, the monopole was originally designed by Paul J Ford and
Company for Airtouch (Verizon) in 1996. It was manufactured by Summit Manufacturing and was
designed for two cellular carriers and an MW antenna. The antennas were as follows:
• (4) LPD 7905/8 panels at the top
•
• (1) 6 -foot microwave at the 70-ft level
• (8) LPD 7905 /8 panels at the 40 -foot level
These antennas were determined by analysis to place the monopole at 87% of capacity.
The proposed Cingular array, as shown in the 2002 drawing set, was intended to be (6) EMS RV65-
1800 panel antennas at the 59 -foot level. This array is both lower on the monopole and smaller in
wind area than the microwave antenna. Your drawings show that there were some antennas at both
platform levels but that there was no microwave antenna.
Therefore, it is our opinion, assuming that the microwave is to be eliminated, that this configuration
• is expected to produce less stress at the base of the monopole than the original design. This
opinion is predicated on the assumption that the current antenna configuration and the proposed
Cingular configuration are the sa • in the descriptions above.
If you have any questions or if = •. r 1. - assistance, please call.
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Sincerely, .p►
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OREGO
Timothy Wolden, PE 9y Ggp Y
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• Principal Artisan Engineering, LLC 4 r , •*.
[EXPIRATION DATE: G/3, /,,`j
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