Twr 3 TIA Inspections Report.NY.Rev 0.080123.pdf

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Inspection and Structural Analysis Douglaston, NY
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This document is a Maintenance and Condition Assessment Report for a 180-foot self-support tower located at 25 251st St in New York, NY, conducted by Tower Engineering Professionals (TEP) on July 18, 2023. The comprehensive inspection was performed in accordance with ANSI/TIA-222-H Annex J standards and identified multiple maintenance recommendations, including addressing loose and missing bolts, corrosion on tower hardware and components, and issues with grounding connections and abandoned equipment.

Key observations and recommendations include: replacing loose A325 bolt assemblies, treating corrosion on tower legs and bracing with cold galvanizing compound, addressing missing nut locking devices on flange/bracing bolts, cleaning and treating surface corrosion on waveguide hanger hardware, removing unused hardware and abandoned equipment, installing a lightning rod at the top of the tower if required by FAA, and properly securing equipment mounts. The tower's plumb and twist measurements were also evaluated, with most measurements falling within acceptable tolerances, though one section between 161-ft and 149-ft showed a deflection that did not meet the allowable standard.

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July 27, 2023

Dejian Xu Tower Engineering Professionals, Inc.

Technical Manager 326 Tryon Road Colliers Engineering & Design, Inc. Raleigh, NC 27603

(856) 242-2049 (919) 661-6351 dejian.xu@collierseng.com SIReview@tepgroup.net

Subject: Maintenance and Condition Assessment Report

FCC Designation ASR Number: N/A

Owner Designation: Owner Site Name: FAA – Tower 3

Inspection Firm Designation: TEP Project Number: 332312.865172

Site Data: 25 251st St New York, NY 11362 Latitude N 40° 45’ 23.91”, Longitude W 73° 43’ 36.52” 180 Foot – Self Support Tower

Dear Mr. Xu, Tower Engineering Professionals (TEP) completed a periodic inspection for the above referenced site. The onsite investigation was performed by Timothy Meyer and Steven Flowers of TEP during the July 18, 2023 site visit. The inspection was in accordance with the ANSI/TIA-222-H Annex J: Maintenance and Condition Assessment (Normative), including all addendums. The checklist is pages 3 thru 9 of this report.

Observations and recommendations are listed herein. The inspection included observation of tower members, bolted connections, and foundations above grade. For the purpose of this inspection, the tower legs were named by letter according to the magnetic azimuth defined by a line from the center of tower to the leg. “A” leg is the leg closest to magnetic north, followed clockwise by “B”, “C” and “D”.

Thank you for the opportunity to provide this service for you. If you have any questions or comments, please contact our office.

Sincerely, Tower Engineering Professionals, Inc. (TEP) Ronnie E. Glover, P.E.

07/27/2023

180-ft Self Support Tower Maintenance and Condition Assessment Report July 27, 2023 TEP Project Number 332312.865172 FAA – Tower 3

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

ANSI/TIA-222-H MAINTENANCE AND CONDITION ASSESSMENT

A. STRUCTURE CONDITION

B. FINISH

C. LIGHTING (external portions of components only)

D. GROUNDING

E. APPURTENANCES SUCH AS MOUNTS, ANTENNAS, AND LINES

F. OTHER APPURTENANCES (ICE SHIELDS, WALKWAYS, PLATFORMS, CLIMBING FACILITIES,

SENSORS, FLOODLIGHTS, ETC.)

G. INSULATORS (BASE INSULATOR, AM DETUNING KITS, FIBERGLASS RODS, PROCELAIN

INSULATOR, NON-METALLIC GUYS, ETC.)

H. GUYS

I. CONCRETE FOUNDATIONS

J. GUYED MAST ANCHORS

K. STRUCTURE ALIGNMENT

EXECUTIVE SUMMARY

APPENDIX A: TOWER PLUMB AND TWIST MEASUREMENTS

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

ANSI/TIA-222-H MAINTENANCE AND CONDITION ASSESSMENT

A. STRUCTURE CONDITION

A.1. Damaged members (legs and bracing)

Okay Possible Improvement Needs Repair Not Applicable Notes:

A.2. Loose members

Okay Possible Improvement Needs Repair Not Applicable Notes:

A.3. Missing members

Okay Possible Improvement Needs Repair Not Applicable Notes:

A.4. Loose and/or missing bolts and/or nut locking devices Okay Possible Improvement Needs Repair Not Applicable

Notes: Loose bolts and missing nut locking devices observed. See Executive Summary for details and recommendations.

A.5. Visible cracks in welded connections including cracks underneath canister mounts for flag poles and other similar connections (cracks in base metal may only be visible on the inside surface of a pole)

Okay Possible Improvement Needs Repair Not Applicable Notes:

A.6. Pole flange and base plate cracks visible in base metal or at ends of plate stiffeners

Okay Possible Improvement Needs Repair Not Applicable Notes:

A.7. Record temperature, wind speed and direction, & other environmental conditions

Okay Possible Improvement Needs Repair Not Applicable Notes: 83°F, South wind 9mph

B. FINISH

B.1. Paint and/or galvanizing condition

Okay Possible Improvement Needs Repair Not Applicable Notes: The galvanized coating and paint on the tower legs and bracing is nearing the end of its service lifespan. See Executive Summary for details and recommendations.

B.2. Rust and/or corrosion condition including mounts and accessories

Okay Possible Improvement Needs Repair Not Applicable Notes: Corrosion was observed in multiple locations. See Executive Summary for details and recommendations.

B.3. FAA or ICAO color marking conditions

Okay Possible Improvement Needs Repair Not Applicable Notes:

B.4. Water collection in members (to be remedied, e.g., unplug drain holes, etc.)

Okay Possible Improvement Needs Repair Not Applicable Notes:

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

C. LIGHTING (external portions of components only) C.1. Conduit, junction boxes, and fasteners (weather tight and secure)

Okay Possible Improvement Needs Repair Not Applicable Notes: A junction box was observed missing a cover. See Executive Summary for details and recommendations.

C.2. Drains and vents openings (unobstructed)

Okay Possible Improvement Needs Repair Not Applicable Notes:

C.3. Wiring Condition

Okay Possible Improvement Needs Repair Not Applicable Notes:

C.4. Light lenses

Okay Possible Improvement Needs Repair Not Applicable Notes:

C.5. Bulb condition

Okay Possible Improvement Needs Repair Not Applicable Notes:

C.6.a. Controllers (Flasher)

Okay Possible Improvement Needs Repair Not Applicable Notes:

C.6.b. Controllers (Photo control)

Okay Possible Improvement Needs Repair Not Applicable Notes:

C.6.c. Controllers (Alarms)

Okay Possible Improvement Needs Repair Not Applicable Notes:

C.7. Obstructions to lighting system.

Okay Possible Improvement Needs Repair Not Applicable Notes:

D. GROUNDING

D.1. Grounding (Connections)

Okay Possible Improvement Needs Repair Not Applicable Notes: Mechanical grounding connections observed at the base of the tower legs. See Executive Summary for details and recommendations.

D.2. Grounding (Corrosion)

Okay Possible Improvement Needs Repair Not Applicable Notes:

D.3. Grounding (Lightning protection)*

Okay Possible Improvement Needs Repair Not Applicable Notes: No Lightning rod is installed to the top of tower. See Executive Summar for details and recommendations.

*Lightning rods are not required for the protection of the structure in accordance with this Standard but may be required at or near the top of the structure for the protection of equipment or lighting systems.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

E. APPURTENANCES SUCH AS MOUNTS, ANTENNAS, AND LINES

E.1.a. Antenna and Mounts (Proper tie-back of microwave dishes)

Okay Possible Improvement Needs Repair Not Applicable Notes:

E.1.b. Antenna and Mounts (Damage to supporting structure at connections)

Okay Possible Improvement Needs Repair Not Applicable Notes:

E.1.c. Antenna and Mounts (Defects, deformations, loose, missing members, etc.)

Okay Possible Improvement Needs Repair Not Applicable Notes:

E.1.d. Antenna and Mounts (Loose or missing hardware)

Okay Possible Improvement Needs Repair Not Applicable Notes:

E.1.e. Antenna and Mounts (Condition of antenna covers)

Okay Possible Improvement Needs Repair Not Applicable Notes:

E.2.a. Feed Lines (Flanges, seals, dents, jacket damage, grounding, etc.)

Okay Possible Improvement Needs Repair Not Applicable Notes: Multiple cut/abandoned coax were observed. See Executive Summary for details and recommendations.

E.2.b. Feed Lines (Properly secured/supported on the structure and mount)

Okay Possible Improvement Needs Repair Not Applicable Notes:

E.2.c. Feed Lines (Hanger condition (snap-ins, bolt on, kellum grips, etc.))

Okay Possible Improvement Needs Repair Not Applicable Notes: Surface corrosion was observed on the waveguide hanger hardware. See Executive Summary for details and recommendations.

E.2.d. Feed Lines (Secured to structure (waveguide ladder))

Okay Possible Improvement Needs Repair Not Applicable Notes:

F. OTHER APPURTENANCES (ICE SHIELDS, WALKWAYS, PLATFORMS, CLIMBING

FACILITIES, SENSORS, FLOODLIGHTS, ETC.)

F.1. Other Appurtenances (Condition) Okay Possible Improvement Needs Repair Not Applicable

Notes:

F.2. Obstructions to climbing path or safety climb systems

Okay Possible Improvement Needs Repair Not Applicable Notes:

F.3. Other Appurtenances (Defects, deformations, loose, or missing members, etc.)

Okay Possible Improvement Needs Repair Not Applicable Notes:

F.4. Other Appurtenances (Loose or missing hardware)

Okay Possible Improvement Needs Repair Not Applicable Notes:

F.5. Other Appurtenances (Secured to Structure)

Okay Possible Improvement Needs Repair Not Applicable Notes: Unused hardware, improper connections and abandoned equipment were observed. See Executive Summary for details and recommendations.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

G. INSULATORS (BASE INSULATOR, AM DETUNING KITS, FIBERGLASS RODS,

PROCELAIN INSULATOR, NON-METALLIC GUYS, ETC.)

G.1. Insulators (Cracking and chipping) Okay Possible Improvement Needs Repair Not Applicable

Notes:

G.2. Insulators (Cleanliness)

Okay Possible Improvement Needs Repair Not Applicable Notes:

G.3. Insulators (Spark gaps)

Okay Possible Improvement Needs Repair Not Applicable Notes:

G.4. Isolation transformer

Okay Possible Improvement Needs Repair Not Applicable Notes:

G.5. Insulators (Bolts and connection secure)

Okay Possible Improvement Needs Repair Not Applicable Notes:

G.6. Insulators (Delamination, UV degradation, rod slippage)

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

H. GUYS

H.1. Guy strand condition (corrosion, breaks, nicks, kinks, etc.)

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.a.i. Guy Hardware Conditions (Turnbuckles or equivalent (threaded extended past body))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.a.ii. Guy Hardware Conditions (Turnbuckles or equivalent (secure and safety properly applied))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.a.iii. Guy Hardware Conditions (Turnbuckles or equivalent (cracks, defects, damage, etc.))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.b. Guy Hardware Conditions (Cable thimbles)

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.c. Guy Hardware Conditions (Ice clips)

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.d.i. Guy Hardware Conditions (Cable connectors (Cable clamps applied properly and bolts tight)

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.d.ii. Guy Hardware Conditions (Cable connectors (Wire serving))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.d.iii. Guy Hardware Conditions (Cable connectors (Slippage or damaged strands))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.d.iv. Guy Hardware Conditions (Cable connectors (Deadend grips fully wrapped, end sleeve/ice clips (on anchor end)))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.d.v. Guy Hardware Conditions (Cable connectors (Poured sockets secure and showing no separation or twisting))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.d.vi. Guy Hardware Conditions (Cable connectors (Shackles, bolts, pins, and cotter pins))

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.2.e. Guy Hardware Conditions (Inspect tension rods/anchor rods welded to fan plates for fatigue cracks)

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.3.a. Measure guy tensions

Okay Possible Improvement Needs Repair Not Applicable Notes:

H.3.b. Record temperature, wind speed and wind direction

Notes: See A.7. for temperature and wind.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

I. CONCRETE FOUNDATIONS

I.1.a. Ground condition (Settlement, movement or earth cracks)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.1.b. Ground condition (Erosion)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.1.c. Ground condition (Site condition (standing water, drainage, trees, etc.))

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.2.a. Anchorage condition (Top and bottom base plate nuts tight)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.2.b. Anchorage condition (Nut locking device)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.2.c. Anchorage condition (Grout condition)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.2.d. Anchorage condition (Anchorages)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.2.e. Anchorage condition (Anchor rods)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.3.a. Concrete condition (Cracking, spalling, or splitting)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.3.b. Concrete condition (Chipped or broken concrete)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.3.c. Concrete condition (Honeycombing)

Okay Possible Improvement Needs Repair Not Applicable Notes:

I.3.d. Concrete condition (Low spots to collect moisture)

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

J. GUYED MAST ANCHORS

J.1. Guy Mast Anchors (Settlement, movement or earth cracks)

Okay Possible Improvement Needs Repair Not Applicable Notes:

J.2. Guy Mast Anchors (Grade sloped away from anchors)

Okay Possible Improvement Needs Repair Not Applicable Notes:

J.3. Guy Mast Anchors (Anchor shaft condition below grade)

Okay Possible Improvement Needs Repair Not Applicable Notes:

J.4. Guy Mast Anchors (Corrosion control measures (galvanizing, coating, concrete encasement, cathodic protection systems, etc.))

Okay Possible Improvement Needs Repair Not Applicable Notes:

J.5. Anchor heads above grade (clear of vegetation, obstructions, etc. and turnbuckles free to articulate)

Okay Possible Improvement Needs Repair Not Applicable Notes:

K. STRUCTURE ALIGNMENT

K.1. Structure Plumb and Twist

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

A.4. Loose and/or missing bolts and/or nut locking devices

Observation:

(2) Loose 9/16"Ø x 2" diagonal bolt were observed on the A-leg and C-legs at 41-ft.

Recommendation:

Replace the entire A325 bolt assembly and tighten in accordance with manufacturer specifications.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

A.4. Loose and/or missing bolts and/or nut locking devices

Observation:

Missing nut locking device were observed on flange/bracing bolts throughout the tower including the following:

The lowest horizontal on the AB and DA face.

The base of the C and D leg.

The center gusset plate on all faces at 10-ft.

The C and D leg flanges at approximately 20-ft.

Recommendation:

Install a pal nut on the flange bolt or install a monitor line on the nut. Ensure all bolts are installed with a nut locking device.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

B.1. Paint and/or galvanizing condition

Observation:

The galvanized coating and paint on the tower legs and bracing is nearing the end of its service lifespan.

Recommendation:

Monitor the coating condition during the next inspection cycle. If the condition worsens, clean and coat the members with a cold galvanizing compound containing at least 95% zinc.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

B.2. Rust and/or corrosion condition including mounts and accessories

Observation:

Corrosion was observed on (flange/bracing) hardware throughout the tower.

Recommendation:

All areas of corrosion should be thoroughly cleaned and treated with two coats of a brush-on cold galvanizing compound containing at least 95% zinc. If during this process any section loss is observed, the hardware should be replaced with one of equal size and grade.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

B.2. Rust and/or corrosion condition including mounts and accessories

Observation:

Surface corrosion was observed:

The lighting system conduit and hardware at all locations.

On the climbing ladder.

Recommendation:

Thoroughly clean all areas of corrosion and apply two coats of a brush-on cold galvanizing compound containing at least 95% zinc. If during this process any material loss is observed, replace the conduit and ensure proper function.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

B.2. Rust and/or corrosion condition including mounts and accessories

Observation:

Corrosion was observed on multiple mounts at 160-ft.

Recommendation:

Notify the equipment owner. All areas of corrosion should be thoroughly cleaned and treated with two coats of a brush-on cold galvanizing compound containing at least 95% zinc. If during this process any section loss is observed, the appurtenance or hardware should be replaced with one of equal size and grade.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

C.1. Conduit, junction boxes, and fasteners (weather tight and secure)

Observation:

A junction box is missing the cover at the top of the tower.

Wires are tied together using electrical tape and no wire nuts.

Recommendation:

Properly join wires and install missing junction box cover to ensure all connections are adequate and weather tight.

D.1. Connections

Observation:

Mechanical grounding connections were observed at the base of the A, B, and C legs. No grounding was observed at the base of the D leg.

Recommendation:

Repair or replace the grounding conductor with an exothermic connection to the tower base. Ensure it is properly bonded to the tower ground ring in accordance with Motorola R56 standards.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

D.3. Lightning protection (secured to structure)

Observation:

No Lightning rod is installed to the top of tower.

Recommendation:

If required by FAA, install a lightning rod at the top of the tower and ensure it is the highest appurtenance.

E.2.a. Feed Lines (Flanges, seals, dents, jacket damage, grounding, etc.)

Observation:

Cut/Abandoned coax was observed at the following:

(1) FH 1/2" at the base of the tower and extend up the tower to 46-ft on the CD face.

(1) SM 7/8"ø cut/abandoned at the base of the tower and extend up the tower to 160-ft on the C-leg.

Recommendation:

Confirm there are no future plans for the abandoned coax and remove the coax from the tower to eliminate unnecessary loading.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

E.2.c. Feed Lines (Hanger condition (snap-ins, bolt on, kellum grips, etc.))

Observation:

Surface corrosion was observed on the waveguide hanger hardware throughout the tower.

Recommendation:

All areas of corrosion should be thoroughly cleaned and treated with two coats of a brush-on cold galvanizing compound containing at least 95% zinc. If during this process any section loss is observed, the appurtenance or hardware should be replaced with one of equal size and grade.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

EXECUTIVE SUMMARY

Photographs Observations and Recommendations

F.5. Other Appurtenances (Secured to Structure)

Observation:

Improperly secured equipment was observed in the following areas:

Unused hardware was observed at 23-ft on the CD face, 25-ft on the C leg, and 68-ft on the C leg.

The stabilizer arm connection brackets for the antenna mounts at 180-ft-ft are installed incorrectly, typical of all mounts at the top of tower.

An abandoned Omni was observed on the AB face at the top of the tower.

Recommendation:

Confirm there are no future plans for the hardware and then remove it from the tower to eliminate unnecessary loading.

Replace stabilizer arm connections with a manufacturer-approved connection.

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

APPENDIX A: TOWER PLUMB AND TWIST MEASUREMENTS

Table A-1: Lateral Deflection Measurements

Reference Elevation

(above conc.)

Resultant Deflection (in)

Allowable Resultant

Deflection (in) per TIA

Resultant Deflection Between Reference

Elevations (in)

Allowable Deflection Between Reference

Elevations (in) per TIA

T ow er P lu m b

161-ft 1.37 OK ±4.83

0.65 NG ±0.36

149-ft 0.73 OK ±4.47

0.37 OK ±0.54

131-ft 1.08 OK ±3.93

0.21 OK ±0.54

113-ft 0.91 OK ±3.39

0.21 OK ±0.54

95-ft 0.75 OK ±2.85

0.36 OK ±0.54

77-ft 0.43 OK ±2.31

0.00 OK ±0.54

59-ft 0.43 OK ±1.77

0.30 OK ±0.54

41-ft 0.17 OK ±1.23

0.17 OK ±0.54

23-ft 0.00 OK ±0.69

0.00 OK ±0.69

0-ft 0.00 OK ±0.00

Tower Engineering Professionals. Inc.

326 Tryon Road, Raleigh, NC 27603 (o) 919-661-6351 (f) 919-661-6350 www.tepgroup.net

Table A-2: Tower Twist Measurements

Reference Elevation

(above conc.)

Twist with Respect

To Base ()

Allowable Twist with

Respect To Base ()

Relative Twist Between Reference

Elevations ()

Allowable Twist Between Reference

Elevations ()

T ow er T w is t

161-ft 0.71 OK ±5

-0.02 OK ±0.60

149-ft 0.74 OK ±5

0.28 OK ±0.90

131-ft 0.46 OK ±5

0.14 OK ±0.90

113-ft 0.32 OK ±5

0.11 OK ±0.90

95-ft 0.21 OK ±4.75

0.07 OK ±0.90

77-ft 0.13 OK ±3.85

0.01 OK ±0.90

59-ft 0.12 OK ±2.95

0.02 OK ±0.90

41-ft 0.10 OK ±2.05

0.10 OK ±0.90

23-ft 0.00 OK ±1.15

0.00 OK ±1.15

0-ft 0.00 OK ±0

Method:

A transit was used at a distance approximately the tower height away to record the twist and plumb data. The base of the tower was used as the reference point. The relative displacement was measured at each section flange. The transit sight was inverted and the displacement was measured again to eliminate possible discrepancies. This process was repeated at the A, B, C, and D legs. Overall displacement was calculated and compared to tolerances per: ANSI/TIA-222-H.

File details come from the government source that posted it. Updated .