Specifications.pdf

RW 23 ALS Catwalk and Tower Inspection Yeager Airport, Charleston, WV

Request For Quotation for the Inspection and Testing of the Steel Catwalk, Supporting Towers and Guyed Connections Serving the Runway 23 Approach Lighting System at the Yeager Airport in

Charleston, WV

1.1 SCOPE OF WORK

A. Scope: The project addresses the inspection and testing of the catwalk structure, supporting towers and guy wires serving the Approach Lighting System for Runway 23 at the Yeager Airport in Charleston, WV.

B. Description of Existing System: The structure consists of 15 tower masts and 15 sections of catwalk. Mast heights range from 71’ AGL to 283’ AGL. Catwalk spans vary between 130’ to 210’. Catwalk access is from the area near the approach end of runway 23. There is a transverse catwalk at the 1000’ distance onto the catwalk. A total of 112 guy wires have lengths ranging from 40’ to 350’ and diameters between 5/8” and 1-1/8”. Wire is galvanized steel bridge strand.

1.2 REQUIREMENTS

A. The project consists of the following requirements:

1. Visual inspections of:

a. Towers

b. Catwalk structure and grating

c. Guy wires

d. Guy anchors and turnbuckles

e. Climbing devices

2. Measurement of vertical alignment of towers.

3. Measurement of tension in guy wires.

4. Preparation of report documenting findings and recommended corrective actions.

5. Contractor shall refer to FAA order 6930.25A for specific guidance on test procedures

1.3 SPECIFICATIONS

A. Visual Inspection

1. Perform visual inspection of all components to determine physical condition:

a. Identification of damaged, deformed and corroded members (ie, beams, columns, braces, rails)

b. Identification of faulty, failing and corroded structural connections

1) Bolted connection (missing or loose bolts)

2) Welded connections (cracked welds)

c. Identification of loose or displaced grating – not secure to structure

d. Identification of loose or displaced grating – broken welds in grating

e. Identification of corroded grating

f. Identification of faulty or failing climbing/fall protection systems

g. Identification of frayed, faulty, failing or corroded guy wire.

h. Identification of faulty, failing and corroded guy connections

1) At/to tower structure

2) At guy anchor

a) All components at anchors (thimble, turnbuckles, clamps, shackles, safety wire, insulators)

3) Identification of faulty, failing or corroded anchor components

a) Eye bolts and concrete

B. Measurement of Vertical Alignment

1. Measure the vertical alignment of each tower by utilization of precision land surveying equipment.

C. Measurement of Guy Tension

1. Measure and record the tension in each guy wire, noting the wire size, number of strands and grade of steel (if possible). Method of testing shall be

2. Method of testing shall be shunt –type where the test can be conducted without breaking in on the guy to be tested.

3. The tensiometer or dynamometer used shall hold calibrations specifically for the size and strand configuration being tested and shall have a capability of measuring tensions up to 25kips.

4. Measure tension a minimum of three times in each wire and average results.

5. Measurements shall be corrected for temperature from a basis of 60 degrees Fahrenheit.

6. Operation of the testing device shall be in strict accordance with the manufacturers operating instructions.

D. Final Report

1. The report shall document all of the results of visual inspections and measurements.

2. Create a section in the report for each catwalk section and each tower mast.

a. Each CATWALK section of the report shall document the results of the visual inspections as described in section 1.3.A.1. The first catwalk closest to runway shall be identified as “Catwalk Span #3” and the catwalk farthest from runway shall be identified as “Catwalk Span #17”. Subparts of the CATWALK section shall include:

1) Condition

a) Damaged members

b) Structural Connections

c) Grating

d) Climbing Devices

e) Guy Connections (if applicable)

2) Corrective action required.

b. Each TOWER MAST section of the report shall document the results of visual inspections, vertical alignment measurements and guy wire tensions as described in sections 1.3.A.1, 1.3.B and 1.3.C. The first tower mast closest to runway shall be identified as “Tower Mast #4” and the tower mast farthest from runway shall be identified as “Tower Mast #18”. Subparts of TOWER SECTION shall include:

1) Condition

a) Damaged members

b) Structural Connections

c) Climbing Devices (if applicable)

d) Guy Wires

e) Guy Connections

f) Guy Anchors

2) Vertical Alignment

3) Guy Wire Tension

a) Guy wires shall be identified with tower mast # and as right/left, front/back.

b) Measurements shall be compared to Erection Tension listed in attachment.

4) Corrective action required.

E. Safety

1. Contractor shall provide safe working conditions for employees.

2. Contractor is responsible for full compliance with federal OSHA standards and requirements.

3. Contractor is responsible for full compliance with state OSHA standards and requirements.

4. Contractor shall use OSHA compliant fall arrest systems when required.

F. Work Schedule

1. Work shall be completed with 30 days of Notice to Proceed

2. Acceptable work hours are Monday through Friday, 600am – 530pm.

G. Coordination With Facility

1. Contractor shall closely coordinate all activities with FAA at the site.

H. Impact to FAA Facilities

1. Contractor shall not impact existing FAA facilities in any way that would cause disruption to the operation of the ALS or other systems on or near the structure.

I. Temporary Facilities

1. Contractor shall be permitted to utilize 120V power at site after close coordination with

FAA site personnel.

2. Contractor is advised that running water and sanitary facilities are not available at this site.

3. Contractor is responsible for all temporary facilities need to complete the project including, but not limited to lighting, shoring, scaffolding and traffic control, where necessary.

J. Drawings

1. DR.NO.1-E-9405, 1/2 Original Plan and Profile (Attached for Reference)

2. DR.NO.1-E-9405, 2/2 Original Plan and Profile (Attached for Reference)

3. E-5298, 11/11 ALS Misc Steel and Guy Details (Attached for Reference)

END OF STATEMENT OF WORK

DISTRIBUTION: Web Release Only INITIATED BY: AJW-223

U.S. DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION

Air Traffic Organization Policy

ORDER

JO 6930.25A

Formerly 6930.25A

Effective Date:

12/15/2006

SUBJ: MAINTENANCE OF STRUCTURES AND BUILDINGS

1. This maintenance handbook cover page is updated to:

a. Comply with Order 1700.6C, FAA Branding Policy, Use of the FAA Logo, FAA Signature, and DOT Seal.

b. Comply with Order JO 1320.1, Air Traffic Organization (ATO) Prefixes for Directives.

c. To identify new Office of Primary Responsibility (OPR) within the ATO organizational structure.

2. A hardcopy cover page will be issued when a handbook revision is performed and may be issued with the next page change if deemed appropriate by the office of primary responsibility.

for Mary Golia Director, Air Traffic Control Facilities

ORDER

Distribution: ZAF-657; ZAF-607; Initiated By: APM-154

6930.25A

MAINTENANCE OF STRUCTURES AND BUILDINGS

August 8, 1985

DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION

FAA FORM 1320-5 (6-80) USE PREVIOUS EDITION

02/26/2002 JO 6930.25A

CHG 4

RECORD OF CHANGES DIRECTIVE NO. JO 6930.25A CHG 4

CHANGE

TO

BASIC

SUPPLEMENTS

OPTIONAL

CHANGE

TO

BASIC

SUPPLEMENTS

OPTIONAL

1 Signed: 12/30/1986 Released: 03/17/1987

2 Signed: 01/26/1995 Released: 04/04/1995

3 Signed: 11/02/1995 Released: 01/05/1996

4 Signed: 02/26/2002 Released: 10/03/2002

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

Signed:

Released:

8/8/85

FOREWORD

6930.25A

I. PURPOSE.

This handbook provides guidance and prescribes tech-nical stanclads, tolerances, and procedures applicable to the maintenance and inspection of structures and builcl-ings. It also provides infonnation on special methods and techniques that will enable personnel to achieve the main-tenance required. Resources available at the local level may require regional or sector engineering and contractor support for corrections, inspection, or repair in some cases. This information augments information available in instruction books and other directives, and complements Order 60.15A, General Maintenance Handbook for Air-way Facilities.

2. DISTRIBUTION.

This directive is distributed to selected. offices and ser-vices within Washington headquarters, the FAA Techni-cal Center, and the Mike Monroney Aeronautical Center;

and to regional Airway Facilities divisions and field offi-ces having requirements for this directive.

:I. CANCELLATION.

Order 6930.25, Maintenance of Structures and Build-ings, dated December 6, 1976, is canceled.

4. hlAJOR CHANGES.

This revision provides condensed infonnation, reduced periodic maintenance schedules, and other changes as a result of field comments.

5. MAINTENANCE AND MODIFICATION POLICY.

a. Order 6OQ0.15A., this handbook, and the applicable equipment instruction books shall lx c~nsultecl ant1 used together by the maintenance technician in all duties and activities for the maintenance of structures ant1 lmilclings.

These documents shall be considered collectively as the single official source of maintenance policy and direction authorized by the Director, Program Engineering and Maintenance Service. References located in the chapters of this handbook entitled Standards and Tolerances, Peri-odic Maintenance, and Maintenance Procedures shall in-dicate to the user whether this handbook and/or the equipment instruction book shall be consulted for a par-ticular standard, key inspection element or performance parameter, performance check, maintenance task, or maintenance procedure.

b. Order 6032.1A, Modifications to Ground Facilities, Systems, and Equipment in the National Airspace Sys-tem, contains comprehensive policy and direction con-cerning the development, authorization, implementation, and recording of modifications to facilities, systems, and equipment in commissioned status. It supersedes all in-structions published in earlier editions of maintenance technical handbooks and related directives.

6. RECOMMENDATIONS FOR CHANGES.

Preaddressed comment sheets are provided at the back of this order in accordance with Order 1320.40B, Exped-ited Clearance Procedures for Airway Facilities Mainte-nance Directives. Users are encouraged to submit recom-mendations for improvement.

Page i (and ii)

THIS PAGE INTENTIONALLY LEFT BLANK

11/2/95 6930.25A CHG 3

Page iii

TABLE OF CONTENTS

Paragraph Page

Chapter 1. GENERAL INFORMATION AND REQUIREMENTS

1. Objective

2. Scope

3. Inspection and Maintenance Program

4. Safety

5.-9. Reserved.

Chapter 2. TECHNICAL CHARACTERISTICS

10. General

Section 1. STRUCTURES

11. Towers

12. Wood Poles

13. Wood Structures

14. Concrete Structures

15. Metal Structures

16.-20. Reserved.

Section 2. BUILDINGS

21. General

22. Construction Types

23. Foundations

24. Floor Systems

25. Walls

26. Ceilings

27. Roof Systems

Section 3. RADOMES

28. Foam Cored Fiberglass Radomes 29.-39. Reserved.

Chapter 3. STANDARDS AND TOLERANCES

40. General

41. Self-Supporting Towers

42. Guyed Towers

43. Wood Poles

44. Safety Climbing Equipment

45. Pole Steps

46.-50. Reserved.

6930.25A CHG 4 2/26/2002

Page iv

Paragraph Page

Chapter 4. PERIODIC MAINTENANCE

Section 1. STRUCTURES

51. With Use

52. Special Conditions

53. Annual

54.-60. Reserved.

Section 2. BUILDINGS

61. Semi-Annual

62. Annual

63. Biennial

Section 3. RADOMES TYPE FA-10800/A, FA-10321, AND FA-10354

64. Every Three Years.......................................................................................... 20-1 65.-70. Reserved.

Chapter 6. MAINTENANCE PROCEDURES

71. General

Section 1. STRUCTURES

72. Safety Climbing Device

73. Turnbuckles

74. Towers

75. Self-Supporting Towers

76. Guyed Towers

77.-80. Reserved.

Section 2. BUILDINGS

81. General

82. Grading

83. Foundations

84. Floor Systems

85. Crawl Space

86. Walls

87. Ceiling Condensation

88. Roofs

89.-101. Reserved.

Section 3. GENERAL MAINTENANCE

102. Concrete

103. Paint

104. Paint Failures

105. Repainting

106. Caulking

2/26/2002 6930.25A CHG 4

Page v (and vi)

Appendix 1. TOWER INSPECTION CHECKLIST Appendix 2. BUILDING CHECKLIST Appendix 3. HISTORICAL RECORD OF ROOF Appendix 4. ROOF MAINTENANCE INSPECTION LIST

LIST OF TABLES

Table Page

5-1. Withdrawn--CHG 4 5-2. Wire Rope Clips 5-3. Caulking Reference Guide

LIST OF ILLUSTRATIONS

Figure Page

2-1. Raised Floor System 2-2. Fiberglass Modular Buildings -Typical Wall Cross Sections 2-3. Built-Up Roof 2-4. Flashing Types 5-1. Transit Arrangement - Self-Supporting Tower 5-2. Vertical Alignment Problem 5-3. Withdrawn--CHG 4 5-4. Withdrawn--CHG 4 5-5. Transit Arrangement - Guyed Towers 5-6. Vertical Linearity Problem 5-7. Guy Tower Alignment - Setup 5-8. Guy Tower Alignment -Adjustment 5-9. Polyester Resin Gel Time

5-10. Structural Crack Undercutting

8/8/85 6930.25A

CHAPTER 1. GENERAL INFORMATION AND REQUIREMENTS

1. OBJECTIVE.

This handbook provides the necessary guidance, to be used in conjunction with information available in instruc-tion books and other handbooks, for the proper mainte-

. nance of FAA structures and buildings.

2. SCOPE.

c This handbook establishes standards and procedures for maintenance, repairs, and replacement of component parts for all structures and buildings used throughout the National Airspace System.

3. INSPECTION AND MAINTENANCE PROGRAM.

An adequate inspection and maintenance program shall be established to permit the timely detection and correc-tion of deficiencies in order to eliminate major repairs.

The intent of a well-organized maintenance program is to achieve maximum life and serviceability. It is not inten-ded that this life and serviceability be achieved through costly overmaintenance. Planning and sound judgment must be exercised to maintain proper structure and build-ing standards. The success of this program depends upon the individual observation and information feedback ef-forts of all technicians that visit the facility.

4. SAFETY.

The possibility of electrical shock, falIs from elevated structures, and other hazards are ever present while per-forming maintenance. Therefore, personnel shall be par-ticularly mindful of these dangers and shall observe the safe practice recommendations listed in chapter 6 of Order 6000.15A, General Maintenance Handbook for Air-way Facilities.

5.-9. RESERVED.

Chap. 1 Par. 1 Page 1 (and 2)

CHAPTER 2. TECHNICAL CHARACTERISTICS

10. GENERAL.

The structures and buildings covered by this order in- support radar, navigational aids, communications systems, elude all structures and buildings maintained by FAA that and airport runway lighting systems.

c Section 1. STRUCTURES

11. TOWERS. 12. WOOD POLES.

e Towers are open framework structures, commonly con-structed of steel, used to elevate and support radar and communications antennas. Towers are generally self-sup-porting or guyed.

a. Self-Supporting Towers. Self-supporting towers are usually less than 150 feet (46 m) in height and are support platforms for rotating radar antennas, beacon lights, com-munications antennas, other electronic equipment, or runway approach light system hardware supports. Sup-port of the towers is derived from the mechanical strength

a. Wood poles are used to support power and tel-ephone lines, transformers, antennas, and as pile founda-tions for buildings, docks, bridges, and other facilities constructed on water or unstable soils. Critical parameters of poles are of its members and a concrete foundation.

b. Adcock Towers. Adcock towers are insulated, self-supporting towers that were first used for the low-fre-quency ranges that provided four electronically derived courses. Due to advanced methods of electronic air navi-gation, the low-frequency ranges were phased out; how-ever, Adcock towers, types 1 through 10, are still used.

C. Guyed Towers. Guyed towers are tall towers (usu-ally over 150 feet (46 m)), supported or braced laterally with steel cables attached at the top and several inter-mediate points of the tower. These cables are secured to three or more guy anchors located on 120” radials from the base of the tower. These towers may extend up to 459 feet (137 m) above the base and are normally used to sup-port electronic antenna systems for microwave or commu-nications equipment. Current data and construction drawings for each guyed tower structure are usually avail-able at the site and in the sector office and must be refer-enced before making a major repair or tower adjustment.

d. Low Impact Resistance (LIR) Towers. JJR towers are fiberglass structures used to support approach lighting systems which are specially designed and constructed to collapse upon impact with aircraft. Maintenance instruc-tions for these towers are not provided herein as they are included in instruction books.

Chap. 2 Par. 10

(1) Kind of wood.

(2) Circumference at ground line.

(3) Height of pole.

(4) Chemical treatment of pole.

b. Inspection techniques and maintenance procedures for wood poles are contained in Order 6950.18A, Mainte-nance of Electrical Distribution Systems.

13. WOOD STRUCTURES.

Because of its affordability and availability, wood is commonly used on such structures as boat docks, bridges, maintenance platforms, approach lighting system masts, and various accessions such as ladders and stairways.

14. CONCRETE STRUCTURES.

Because of its permanence, concrete is commonly used for structure foundations such as piers, footings, walls, pe-destals, grade beams, piling caps, and slabs. Other con-crete and masonry structures are prefabricated manholes and handholes, retaining walls, curbs, and sidewalks.

15. METAL STRUCTURIES.

Aluminum and steel structures include towers, water tanks, ladders and stairways, and ground counterpoise.

Metal is generally used when strength and ease of erec-tion are prime considerations.

16.-u). RESERVED.

21. GENERAL.

FAA facilities normally include a building to house equipment and personnel. Buildings include all sheds, shelters, and trailers, that enclose or protect the installed FAA equipment. The buildings vary in size and shape;

construction type varies from wood frame to conventional concrete block industrial design to prefabricated, relo-catable fiberglass modular units.

22. CONSTRUCTION TYPES.

The construction methods used for FAA buildings var-ies with the age of the building, its use, and environmen-tal and economic factors.

a. Masonry. Masonry buildings may be constructed of reinforced concrete, concrete blocks, brick, structural clay tile, or rubblestone. This type of construction is used for administrative buildings and other facilities where perma-nence is the primary consideration.

b. Wood Frame. Many older FAA buildings are con-structed of wood and are used for a variety of applica-tions. Although site-constructed buildings now seldom use a wood frame, wood is still used in some prefabricated building designs.

c. Preengineered Steel. Preengineered steel buildings are available in standard sizes and configurations from many manufacturers. The components of these buildings (framing, joists, and wall and roof panels) are fabricated in the manufacturer’s plant and are shipped to the site for erection. These buildings were originally used only for equipment storage, vehicle shelters, and shop space. How-ever, with advances in design and interior finish, they now provide an economical alternative to masonry con-struction for electronic equipment buildings and office buildings.

d. Steel Tank. Steel tank type buildings are being used for new Vortac facilities. These buildings consist of cur-ved galvanized steel panels, bolted together and to a bot-tom flange and top panel, to form what resembles a tin can. The joints between panels are caulked while the in-tersections with the bottom flange and top panel are gas-keted.

e. Prefabricated. Prefabricated buildings are used to house electronic equipment and engine generators, and for storage. These buildings consist of wall, roof, and sometimes floor panels, which are manufactured at the contractor’s plant and shipped to the site. Wood or metal

Chap. 2 Par. 21

6930.25A a/a/a5

Section 2. BUILDINGS framing is built into the panels. Once onsite, the panels e are rigidly interconnected to provide structural integrity and a weathertight seal. Type S buildings are examples of this construction.

f. Fiberglass Modular. This type of building is used when numerous relocations of a facility are anticipated.

Walls, floors, and roofs of the building modules are con-structed of sandwiched material of varying types depend-ing on the building manufacturer. All types of construe-tion offer a high strength-to-weight ratio for ease of trans-portation. Materials are treated to be fire retardant and have good insulating properties. These buildings are pres-ently being used to house engine generators and the air-port surveillance radar, ASR-8.

g. Trailers and Vans. These items are used to house en-gine generators and small, unmanned facilities when a high degree of mobility is required.

23. FOUNDATIONS.

FAA buildings are normally provided with conven-tional concrete foundations unless site conditions require a special design. Conventional foundations consist of rein-forced concrete footings below frost line and reinforced concrete or concrete block foundation walls up to grade. e Concrete slab foundations are normally provided for pre-fabricated buildings or trailer/vans. Most relocatable modular buildings, such as the ASR-8, two module com-plex, are anchored to a special concrete foundation desig-ned by the manufacturer. Poor soil conditions require spe-cial foundation designs such as pier/grade beams or spread footings.

24. FLOOR SYSTEMS.

The floor systems used in FAA buildings generally cor-respond to the construction type used.

I

a. Masonry. Most masonry buildings are designed with concrete slab floors with vinyl or carpet floor covering in the equipment and administrative areas. Where equip-ment requirements dictate, a raised floor system may be provided. (See subparagraph e.)

b. Wood Frame. These buildings are typically provided with wood floor decks with a crawl space be-neath. The floor decks are supported by wood beams and wood floor joists. The floor deck of older buildings usually consists of a wood subfloor covered with a tongue-and-groove flooring surface. Newer buildings are provided with a M- or 34~inch plywood floor deck with vinyl tile or carpet floor covering. l a/am5

c. Preengineered Steel. The floor systems used in ma-sonry buildings also apply to most preengineered steel buildings. At some type S buildings, the floor frame cons-ists of galvanized steel channels to which wood nailers are bolted. This frame is then covered with tongue-and-groove boards and is finished with asphalt tiles or maso-nite panels.

d. Steel Tank. Steel tank type buildings utilize the bare concrete slab as a floor. Simplicity is the key as these buildings are used for unmanned facilities.

.J

e. Prefabricated and Modular. Prefabricated units, modular buildings, and trailers/vans are provided with special floor systems normally constructed of materials used in the walls and roofs of the building and finished with a suitable flooring surface. The floor systems are de-signed to support the building as well as the equipment installed. Modular buildings and trailers will additionally resist forces and shock loads encountered during transport of the building.

f. Raised Floor. The use of raised floor systems is in-creasing as packaging of electronic equipment increases in density. These floor systems consist of a concrete sub-a floor, pedestals, stringer system, and panel modules. (See figure 2-l.) The pedestals are adjustable to provide level-ing of the floor and are anchored to the concrete subfloor to resist seismic as well as live and dead loads. The strin-ger system is an open framework of steel channel, which supports the panel modules. The panel modules are typi-cally 2 by i feet (61 cm) metal or metal-clad wood panels with a vinyl or carpet top surface. The area betwen the subfloor and raised floor is used as a supply air plenum to provide cooled air to electronic equipment.

6930.25A

25. Walls.

a. Masonry. Masonry buildings built in the 1959-66 pe-riod were typically constructed of painted, uninsulated, 8-inch (26 cm) thick concrete block exterior walls and 6-inch (15 cm) thick concrete block interior load-bearing and fire walls. Present construction leans toward steel-reinforced concrete over concrete block.

b. Wood Frame. The walls of these buildings are con-structed of 2- by 4-inch or 2- by 6-inch wood studs. Wall-board is used on the interior of the wall; while the exterior may be finished with wood, vinyl, or aluminum siding, stucco, or brick facing.

c. Preengineered Steel. Preengineered steel buildings have a steel building frame which is bolted to the con-crete foundation walls or concrete slab. Steel wall panels are attached to the exterior of the frame with the steel framework exposed inside. If insulated, fiberglass batt in-sulation usually is exposed and secured inside the wall,

d. Steel Tank. The walls of steel tank type buildings consist of panels made of heavy gauge galvanized steel.

Exterior of panels is unpainted and interior is unfinished.

e. Prefabricated. These walls consist of prefabricated panels, which are framed with wood or steel channels, are covered on both sides with masonite, and contain insula-tion material, Panels may be plain or contain .louvered openings, windows, or doors. These panels are bolted to-gether and are caulked to form a tight structure.

f. Fiberglass Modular. Fiberglass modular building walls are constructed of various materials depending on f-

PANEL MODULES 7

Figure 2-1. Raised Floor System

Chap. 2 Par. 24 Page 5

6930.25A 8/8/85 the building contractor. Sample cross sections of walls are shown in figure 2-2.

I

CHOPPED FIBERGLASS

SKIN WITH GELCOAT

FINISH

PLY ‘v$‘OOD /

SKIN BONDED

TO INNER CORE

\ POLYURETHANE CORE

f

CHOPPED FIBERGLASS

SKIN WITH GELCOAT

FINISH

PLYWOOD

SKIN BONDED

TO INNER CORE

, r RIDGID POLYURETHANE FOAM CORE I

’ L CHOPPED FIBERGLASS SKINS

Figure 2-2. Fiberglass Modular Buidings - Typical Wall Cross Sections

26. CEILINGS.

Ceilings may consist of only the exposed steel or wood framing members; however, they more likely will include some finishing treatment. Types of ceilings include pain-ted hardboard, acoustic tiles glued to hardboard, and drop ceilings. Drop ceilings consist of a stringer system suspen-ded from framing members with removable panels in-stalled on the stringers.

27. ROOF SYSTEMS.

There are many types of roof systems in use on FAA buildings. The type of roof system used depends on the type of construction and the size and location of the building. A complete roof system consists of the roof deck, insulation, waterproof membrane, raceways and roof penetrations, flashing and counterflashing, and the roof drainage system. The integrity of all components must be assured for the success of the total roof system.

a. Built-Up Roofs. One of the most common roof sys-tems found on larger, flat-top buildings is the built-up roof. Built-up roof (BUR) systems consist of an assembly of interacting components; i.e., the structural deck, ther-mal insulation, and bituminous membrane, all designed to protect the building from the elements. (See figure 2-3.) If the system is properly designed, all components support each other.

(1) Deck. The steel, wood, or concrete deck is struc-turally designed to withstand all expected loads and stres-ses caused by wind, snow, and rain, and also to support roof-mounted equipment. The total deflection of the deck with all loads must be compatible with the flexibility limits of the thermal insulation and the built-up mem-brane to avoid separation of one from the other.

OVERLAPPING FIBERGLASS OR FELT

STRIPS, ASPHALT OR TAR SATURATED

I

Figure 2-3. Built-Up Roof

Par. 25 c 818185

(2) Insulation. The thermal insulation is one or more layers of rigid organic or inorganic boards glued or me-chanically attached to the deck. It must be resistant to burning, have good tensile and compressive strength, and contain excellent insulative properties. In addition, it must be structurally capable of supporting the loads im-posed by the several roofing materials stored and equip-ment used by the roofing contractor. It also anchors the roof membrane to the deck.

(3) Bituminous Membrane. The bituminous mem-brane consists of alternate layers of asphalt or coal-tar-sa-turated material (fiberglass or felt) and pure bitumen (as-phalt or coal tar pitch). The exposed surface of the bi-tuminous membrane is protected by a flood coat of bitu-men that is normally covered with select roof gravel to protect the membrane and to limit oxidation from solar action. The gravel also provides dead weight to prevent the roof membrane from lifting.

NOTE: Asphalt is not compatible with coal tar, and the two must not be mixed or placed in con-tact with one another.

b. Asphalt Shingle Roofs. Asphalt shingle roofs are common on wood frame buildings with sloped roofs. This roof system consists of a plywood roof deck, roofing felt underlayment, and asphalt shingles. Asphalt shingles are manufactured of single or multiple units of roofing felt sa-turated and coated on both sides with asphalt and sur-faced on the weather side with mineral granules. Shingles are available in a wide range of colors and shapes, the most common shape being the square-butt, strip type.

c. Asphalt Roll Roofs. Asphalt roll roof systems are similar to the asphalt shingle roofs except that the roofing material comes in long strips rather than separate shing-les. Roll roofing is attached to the deck with nails and as-phalt cement.

d. Metal Roofing. Metal roofing may be encountered on wood frame, masonry, and preengineered steel build-ings. The roofs of preengineered steel buildings are con-structed similar to the walls with steel-ribbed roof panels supported by steel purlins. The two common metal roof systems used on wood and masonry buildings are temepl-ate and corrugated metal.

(1) Temeplate. Temeplate is sheet steel with a lead-tin coating to provide a surface that can be painted. It may be obtained in SO-foot (15 m) rolls, 14 to 28 inches (36 to 71 cm) wide, or as 3-by 6-foot (1 by 2 m) flat sheets. Installation of temeplate roofs is accomplished using cleats to join sections and soldering all seams.

Chap. 2 Par. 27

6930.25A

(2) Corrugated Metal. Corrugated metal roofing is generally made of galvanized iron; however, aluminum, stainless steel, and copper are also used. Installation of these roofs is performed by overlapping the corrugated sheets and nailing to the roof deck, then caulking all seams.

e. Elastomeric Roof Systems. The increased cost of pe-troleum and coal tar products has prompted the develop-ment and use of synthetic compounds for roofs on build-ings that previously would have had built-up roofs. These systems are referred to in the roofing industry as “single-ply” membrane roof systems. They consist of synthetic chemical compounds that produce a material that resists weathering, is easily handled, is impervious to water, and can be economically installed as a roofing system. Four categories of this material are: liquid-applied elastomerics, plastics, synthetic rubber, and modified bitumen.

(1) Liquid-applied materials include Gaco Neopre-ne-Hypalon, Kobacoat, urathane/neoprene/hypalon, and many others that are brushed, rolled, or sprayed onto a roof surface. When cured, it forms a 20- to 40-mil- (0.5- to lmm) thick sheet of elastomeric material. This material can be applied to any shape and type of material that is suitably primed to provide an adequate bond. When cured, it provides a one-piece roof surface with no breaks.

(2) Plastics include polyvinyl chloride (PVC), polyiso-butylene (pib), and chlorinated polyethylene (cpe). This mate&l is produced in sheets of various thicknesses and is marketed under many brand names. The sheets are wel-ded together with cement to prevent leaks.

(3) Synthetic rubber includes EPDM (ethylene-propylene-diene-monomer), neoprene rubber (polychroprene), and butyl rubber (isoprene isobutylene).

This material is also manufactured in sheets that may be lapped and cemented together with a suitable liquid ad-hesive, solvent, or heat weld.

(4) Modified bitumen is asphalt or coal tar that is combined with mineral fillers, fibers, polymers, thermo-plastics, or elastomeric materials to produce a material with improved physical/chemical characteristics. There are many different products available from manufacturers claiming many advantages. All are produced in sheets of various widths and thicknesses. They can be heat welded, hot mopped, or asphalt/coal-tar cemented. Because they are heat weldable, lap joints are easily sealed and difficult roof penetration flashing, edge flashing, and interior drains are easily installed.

6930.25A CHG 3

f. Fiberglass Modular. Fiberglass modular building roofs are composed of roof panels that are constructed of the same materials as the wall panels. The panels are joined to form a weathertight seal.

g. Flashings. Flashings deserve special attention be-cause they are the most common source of roof leaks.

Flashing provides a watertight junction between the roof-ing material and other parts of the structure, and between roof sections. Flashings may be divided into two basic types: base flashings and cap or counter flashings. (See figure 2-4.)

(1) Base Flashing. The base flashing is the actual junction between the roofing material and the.vertical wall, projection, etc., and should be considered as a com-

11/2/95 ponent part of the roof construction. Metal base &.shing is generally used with shingled roofs. The base flashing for built-up roofing should be of a bituminous nature. Metal base flashing is not recommended for built-up roofs.

(2) Cap or Counter Flashing. The cap or counter flashing is usually constructed of metal. This flashing should extend a minimum of 8 inches (20 cm) and a maxi-mum of 16 inches (41 cm) above the roof line and should be set into a reglet extending into the wall at least 1 l/8 inches (29 mm). Through-wall flashings are preferred to reglets, which extend only part way into the wall. The cap or counter flashing protects the base flashing so that all flashing strips and nails are completely covered.

COUNTER

FLASHING 1

-PARAPET

WALL

- REGLET

JOINT

Figure 2-4. Flashing Types

Section 3. RADOMEX

28. FOAM CORED FIDERGLASS RADOIMES.

a. Foam cored fiberglass radomes are built-up curved panels as shown in figure 2-2. The outside skin has a hydrophobic coating which prohibits water absorption.

The panels are bolted together to form a spherical dome.

The radome is equipped with hatches to permit access to lightning protection and obstruction lights. Panel joints are sealed with caulk.

29.39. RESERVED. *

Par. 27

Chap. 3 Par. 40 Page 9 (and 10)

CHAPTER 3. STANDARDS AND TOLERANCES

40. GENERAL.

This chapter prescribes the standards and tolerances for maintenance of structures and buildings, as defined and described in Order 6000.15A, General Maintenance

Handbook for Airway Facilities. All key performance parameters and/or key inspection elements are clearly defined by an arrow placed to the left of the applicable item.

Parameter Ref.

Par. Standard Tolerance

→ 41. SELF-SUPPORTING TOWERS.

a. Withdrawn--CHG 4

b. Towers ≥ 100 feet tall --alignment error

75b One part in 250 NA

→ 42. GUYED TOWERS.

a. All towers-Guy tension 76b Per facility drawings

±300 lbs. (136kg) (temperature corrected to 60°F) (15°C) of specified initial tension

b. Towers ≥ 50 feet tall

(1) Alignment error 76b One part in 400 NA

(2) Linearity 76b One part in 1000 NA

→ 43. WOOD POLES ............................. Order 6950.18A Order 6950.18A

→ 44. SAFETY CLIMBING

EQUIPMENT.

72 As installed As installed

→ 45. POLE STEPS ................................ Order 6950.18A Order 6950.18A

46.-50. RESERVED

Chap 4 Par. 51 Page 11

CHAPTER 4. PERIODIC MAINTENANCE

Section 1. STRUCTURES

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

51. WITH USE. Check the following items each time they are used.

a. Safety Climbing Device. Inspect, repair and replace device as necessary.

44 72

b. Ladders. Inspect for loose, missing, or deteriorated parts. Repair or replace ladder before using.

NA NA

c. Turnbuckles. Inspect and replace turnbuckles as required.

NA 73

d. Elevated Maintenance Platforms. Inspect to ensure that the platform is level with no loose or projecting boards, grating, nails, bolts, etc., which may cause tripping or stumbling.

Inspect handrails for correct placement, security, and absence of sharp edges or splinters. Report unsafe conditions immediately and insure that repairs are made.

NA NA

52. SPECIAL CONDITIONS. Perform the following actions after all storms, high winds, or heavy ice loads.

a. All Towers.

(1) Grounds. Inspect ground area around tower base for hardware (nuts, bolts, washers) that may have come loose from the tower structure. Replace items in their proper position on the tower.

NA NA

(2) Concrete Foundation. Inspect foundation for cracks. Repair concrete cracks with cement, grout, mortar, or elastomer/plastic patching cement.

NA 102

Chap. 4 Page 12 Par. 52

Section 1. STRUCTURES (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

(3) Structural Members. Using binoculars, visually inspect the tower for broken, bent, loose, or missing parts.

Repair damaged or bent parts, and replace parts where necessary.

Secure loose parts and arrange for replacement of remaining damaged parts.

NA NA

(4) Grounding System. Inspect ground straps, cables, and connections for evidence of lightning damage.

Repair and replace parts as necessary.

NA NA

(5) Tower Lighting. Illuminate tower maintenance and obstruction lights to verify that they are in good working order. Repair and replace parts as necessary.

NA NA

(6) Bends and Twists. Observe tower from a distance for vertical bends, curves, or twists.

If any of these conditions exist or are suspect, repair areas.

NA 75a and 76

b. Self-Supporting Towers Observe tower from a distance for vertical alignment. If it is suspected that the tower is leaning, determine amount of leaning using transits, and align tower.

NA 75b

c. Guyed Towers.

(1) Guys. Inspect guy anchors, cables clamps, and hardware for damage. Inspect cable run for unusual sag. Repair and replace parts as necessary. If sag is noted, determine guy tension and adjust guys and align tower if necessary.

NA 76b and c

(2) Vertical Alignment. Observe tower from a distance for vertical alignment.

If it is suspected that the tower is leaning, determine amount of leaning using transits and align tower.

NA 76b and c

Par. 53 Page 13

Section 1. STRUCTURES (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

53. ANNUAL.

a. All Towers.

(1) Grounds. Inspect ground area around tower base for hardware (nuts, bolts, washers) that may have come loose from the tower structure.

Replace items in their proper position on the tower.

NA NA

(2) Concrete Foundation. Inspect tower foundation for dusting, spalling, cracking, settling, and tilting.

Inspect grout pads under base plates to insure they are sound. Repair as required.

NA 102

(3) Structural Members. Climb entire length of tower, examining all structural members, antennas, mounts, hardware, and welds for loose or missing hardware, stress cracks, broken or bent members, rust, and corrosion. Tighten loose hardware and replace missing hardware as soon as possible. Replace bent or broken members. Note locations of stress cracks and request regional office assistance to repair. If rust and corrosion damage is extensive, notify sector office to schedule repaint of entire tower. If rust and corrosion damage is limited, clean, prime, and repaint.

NA 105

(4) Grounding System. Inspect ground straps cables, and connections for evidence of lightning damage. Repair and replace parts as required.

NA NA

(5) Tower Lighting. Illuminate tower maintenance and obstruction lights to verify that they are in good working order. Repair and replace parts as necessary.

NA NA

Page 14 Chap. 4 Par. 53

Section 1. STRUCTURES (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

b. Self-Supporting Towers

(1) Bends and Twists. Observe tower from a distance for vertical bends, curves, or twists. If any of these conditions exist or are suspect, repair areas.

NA 75a

(2) Vertical Alignment.

(a) Towers < 100 feet tall. Observe tower from a distance. If leaning is suspected, verify plumb of tower using transit. Align tower if needed.

NA 75b

(b) Towers ≥ 100 feet tall. Verify plumb of tower using transit. Align tower if needed.

41b 75b

c. Withdrawn--CHG 4

d. Guyed Towers

(1) Guy Cables. Inspect guy cables, attachment points, and hardware. Repair and replace parts as needed.

NA 76b

(2) Guy Cable Clearance. Inspect area around guy cables to insure clearance from vegetation. Prune back or remove any trees that may damage guy cables.

NA NA

(3) Vertical Alignment.

(a) Towers ≤ 50 feet tall. Verify plumb using level. If problem is indicated, use transit and align tower.

NA 76b

(b) Towers > 50 feet tall. Verify plumb of tower using transit. Align tower if required.

42b 76b

(4) Vertical Linearity.

(a) Towers ≤ 50 feet tall. Observe tower from a distance. If problem is indicated, use transit and adjust.

NA 76b

(b) Towers > 50 feet tall. Verify linearity of tower using transit. Adjust tower if required.

42b 76b

(5) Guy Tension. Determine guy tension, using shunt dynamometers.

42a 76b

e. Wood Poles. See inspection and maintenance procedures of Order 6950.18A.

6950.18A 6950.18A

Par. 53 Page 15

Section 1. STRUCTURES (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

f. Wood Structures.

(1) Members. Visually inspect all members for cracks and surface decay.

Sound all members for internal rot. Replace any members showing decay, rot, or extensive cracks.

NA NA

(2) Pole Tops. Visually inspect the tops of support poles. If signs of weathering or cracks are present, seal top of pole with preservative and install a suitable metal pole cap.

NA NA

(3) Joints. Probe all joints with a blunt tool or pocket knife to assure that sound wood exists in all members.

Replace members that show decay or rot at the joints.

NA NA

(4) Fastening Hardware. Inspect all bolts, nuts, and lag bolts for rust and tightness. Replace rusted hardware.

Saturate bolt and hole with preservative before tightening hardware. Where lag bolts will not tighten, use the next larger diameter lag bolt. Inspect bolt holes for elongation and replace members so affected.

NA NA

(5) Paint. Inspect condition of painted surfaces for chipping, peeling, cracking, or separation. Where these conditions exist, probe or drill the wood beneath the paint to ensure that the wood is sound.

Spot paint or repaint structure as required.

NA 105

g. Concrete Structures. Inspect for cracks chipping, spalling, or dusting. Repair areas as required. Note location, length, and width of cracks for comparison during next inspection.

Repeated or increasing cracks indicate problems that require regional engineering assistance.

NA 102

Page 16 Chap. 4 Par. 53

Section 1. STRUCTURES (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

h. Metal Structures

(1) Structural Members. Visually inspect members for cracks, breaks, and bending.

Inspect all welds for cracks.

Straighten bent members. Weld or replace cracked members.

Replace broken members.

NA NA

(2) Fastening Hardware. Inspect all fastening hardware (bolts, nuts, screws) for rust and tightness. Inspect bolt locations for elongated holes.

Replace rusted hardware and members with elongated holes.

Tighten all hardware as required.

NA NA

(3) Rust and Corrosion. Inspect structural members for rust and corrosion. Replace severely corroded members. Remove rust, using a wire brush and chemical rust remover. Repaint as required.

NA 105

(4) Paint. Inspect paint for peeling, flaking, or separation.

Spot paint or repaint entire structure if required.

NA 105

54.-60. RESERVED.

Section 2. BUILDINGS

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

61. SEMI-ANNUAL. Coincidentlly with other PM's, visually inspect entire facility/site to assure integrity and security of all buildings, structures, antennas, etc. In environments where rapid deterioration is possible, visits should be at least quarterly.

NOTE: We believe a facility/site unvisited for a year represents high risk.

1/26/95 6930.25A CHG 2

Par. 62 Page 17

Section 2. BUILDINGS (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

62. ANNUAL

a. Roofs of Large Buildings (ARTCC) flight service stations (FSS), terminal radar approach control (TRACON), etc.).

NA 88b

b. Roofs (Small/Medium Buildings).

(1) Built-Up ........................................................................................... NA 88c

(2) Elastomeric ...................................................................................... NA 88d

(3) Asphalt Shingle................................................................................ NA 88e

(4) Asphalt Roll ..................................................................................... NA 88f

(5) Terneplate ........................................................................................ NA 88g

(6) Corrugated Metal ............................................................................. NA 88h

(7) Preengineered Steel and Steel Tank................................................. NA 88i

(8) Prefabricated .................................................................................... NA 88i

(9) Fiberglass Modular .......................................................................... NA 88i

63. BIENNIAL.

a. Grading. Inspect exterior of foundation building for proper drainage of water away from building. Note evidence of standing water against or under building and schedule corrective grading if necessary.

NA 82

b. Foundation. Inspect exterior of foundation for cracks, vertical or horizontal displacement, alignment, sags, and uplift.

Insure that supporting piers and walls line up and are plumb, and that all tops are level. Record location and extent of all cracks and repair. Measure and record amount of foundation movement. Record which walls and piers are out of plumb and amount and direction of leaning. File data for comparison with subsequent inspections.

NA 83 and 102

c. Floor Systems.

Page 18 Chap. 4 Par. 63

Section 2. BUILDINGS (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

(1) Concrete. Inspect concrete floors for cracks and dusting. Repair areas. If concrete floor is covered with vinyl tile, replace any broken, chipped or loose tiles.

NA 84a and 102

(2) Wood. Inspect and repair where needed ......................................... NA 84b

(3) Raised. Inspect raised floor surface to insure that it is level with no dips or mounds.

Inspect panel modules for damage and insure that they mate properly to form a smooth surface.

Raise panels in various areas of the room and inspect subfloor for moisture and cleanliness.

Relevel floor, using pedestal adjustment. Replace damaged panel modules. Clean subfloor area and seal if moisture is present.

NA 84c

d. Crawl Space. Inspect area to insure that crawl space is clean and dry.

NA 85

e. Walls.

(1) Wood Frame .................................................................................... NA 86

(a) Inspect exterior of walls for cracks or openings that would compromise weathertightness.

Inspect the caulking at the wall/roof interface for breaks. Inspect caulking around windows, conduits, vents, ducts, and all other wall openings.

Check door threshold and weatherstripping.

Inspect protective surface (paint, siding, etc.)

for damage.

(b) Inspect interior of walls for cracks and water stains. Pay particular attention to the area around wall openings.

(2) Concrete/Masonry............................................................................ NA 86

(a) Inspect exterior of walls for cracks in blocks or mortar joints.

(b) Inspect caulking at the wall/roof interface for breaks. Recaulk as necessary.

Par. 63 Page 19

Section 2. BUILDINGS (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

(c) Inspect caulking around all wall openings.

Recaulk as necessary.

(d) Check door weatherstripping and threshold to insure weathertightness. Replace weatherstripping if required.

(e) On parapet walls, check the parapet wall caps to insure that they are in place, weathertight, and sloped to dispel water.

(f) Inspect paint on exterior and interior surfaces for chipping, peeling, fading, etc. and repaint if necessary.

(g) Inspect interior of walls, top to bottom, for cracks and water stains.

(3) Preengineered Steel and Steel Tank................................................. NA 86

(a) Inspect exterior walls for loose, broken, or bent panels. Tighten, straighten, or replace panels as needed.

(b) Inspect caulking between panels for cracks, pliancy, and breaks. Recaulk as necessary after removing old caulking.

(c) Inspect caulking around wall openings.

Recaulk as necessary.

(d) Inspect panels for rust and paint condition (if painted).

Remove rust and repaint as necessary.

(e) Inspect interior walls for any signs of water leakage. If found, determine source of water and seal using caulk.

(4) Prefabricated .................................................................................... NA 86d

(a) Inspect prefabricated wall panels for bulges, gashes, and frame/hardboard separation.

(b) Inspect caulking between panels for pliancy, cracks, and breaks. If required, remove existing caulk and recaulk panels.

6930.25A CHG 3 11/2/95

Page 20 Chap. 4 Par. 63

Section 2. BUILDINGS (Continued)

Reference Paragraph Maintenance Activities Standards &

Tolerances Maintenance Procedures

(c) Inspect…