717OVERHEAD ROADWAY SIGN STRUCTURE

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715.03Construction Requirements

The overhead roadway sign structures shall be installed in accordance with the requirements given in Section 718, STRUCTURES FOR TRAFFIC CONTROL DEVICES AND HIGHWAY LIGHTING. The special brackets, braces, etc. which support the auxiliary equipment and to which the sign panels are affixed are classified as an integral part of the structure and shall be installed as noted in this Article or detailed on the plans or approved drawings.

715.04Method of Measurement

Overhead Roadway Sign Structures will be measured separately by individual structures, complete in place and fully operational. Sign panels will be measured and paid for under Section 710, with the installation, mounting, etc. performed as provided therein.

715.05Basis of Payment

Complete and accepted overhead roadway sign structures, measured as noted above, will be paid for at the contract lump sum price bid for each structure. This payment shall be full compensation for all work and materials (except sign panels) necessary for an operational sign, complete in place on its supports at the designated locations. The contract lump sum price shall also include all costs for designing the sign structure, constructing foundations and furnishing and installing all other materials for the completion of the sign.

715-A Overhead Roadway Sign Structure No. ___ - per lump sum OVERHEAD ROADWAY SIGN STRUCTURE RENOVATION AND RELOCATION

717.01Description

This Section shall cover the work of renovating designated existing overhead roadway sign structures. The renovation may include, but not be limited to, refurbishing the sign panels, reworking or replacing the electrical system, and reworking the support system. The plans will show the extent of work to be performed under this item. This Section shall also cover the work of relocating, or partially relocating, designated existing overhead roadway sign structures. The relocation may include, but not be limited to, removal or relocation of the existing signs, their supports, and foundations, and the reinstallation of the sign assemblies on their supports with new foundations as detailed on the plans. The plans will show the extent of work to be performed under this item. If new supports or foundations are required, the Contractor shall be responsible for the same design requirements as specified in Article 715.01.

717.02Materials

Materials involved in the work under this Section will be basically the reuse of existing signs and their supports. No bolts, nuts, or washers which are removed shall be reused; new materials shall be equal to or better in design than the old materials. Any replacement or new materials required shall comply with the appropriate requirements of Article 715.02.

717.03Construction Requirements

The renovation of existing overhead roadway sign structures may include work to the existing sign, sign structure, or sign appurtenances. The plans will show the work to be done under the renovation item. OVERHEAD ROADWAY SIGN STRUCTURE RENOVATION AND RELOCATION 615

After completion of the renovation, the sign panels shall be cleaned with approved cleaning material.

The relocation of existing overhead roadway sign structures shall, in general, require the removal of a complete sign assembly (panels, lights, walkway, and supports), the construction of a new foundation, and the reinstallation of the assembly at a new designated location. The Contractor shall notify the Project Manager by letter, with a copy to the Bridge Engineer, of the date of the relocation of a sign structure. This notification shall be given no later than two weeks before the removal of the structure. The Contractor shall arrange for the welds of relocated structures to be inspected and tested by an AWS Certified Welding Inspector in accordance with the requirements given in Section 891. The inspection and testing of the welds shall be done after the installation of the sign structure. The method of removal shall be that of the Contractor, however, any damage to the sign structure caused by improper removal procedures shall be repaired by the Contractor without additional compensation. Damaged members or parts shall be repaired using materials complying with the provisions of Article 715.02 or as directed. Any dismantling of the sign assembly as well as reassembly shall be performed in such a manner as to preclude damaging the assembly materials. Structure foundations being abandoned shall be removed to a depth of not less than one foot below the existing ground surface and the area backfilled as directed with suitable material. The installation of the relocated overhead sign structures shall be as prescribed in Article 715.03 for new structures. After completion of the reinstallation, the sign panels shall be cleaned with approved cleaning material.

717.04Method of Measurement

Measurement of renovated overhead roadway sign structures will be on a lump sum basis for each individual structure renovated, complete in place and fully operational. Measurement of relocated overhead roadway sign structures will be on a lump sum basis for each individual structure relocated, complete in place and fully operational. Any new sign panels needed will be measured and paid for under Section 710, with the installation, mounting, etc. performed as outlined therein.

717.05Basis of Payment

Complete and accepted renovated overhead roadway sign structures, measured as noted above, will be paid for at the contract lump sum bid for each sign structure, which shall be full compensation for renovating the sign structure according to plan details and for all materials, except sign panel, equipment, tools, labor, and incidentals necessary to complete this item of work. Complete and accepted relocated overhead roadway sign structures, measured as noted above, will be paid for at the contract lump sum price bid for each sign structure, which shall be full compensation for all work and materials, except sign panels, necessary for the removal and relocation of the sign structure (panel, lights, walkway, and supports) complete in place on its supports at the designated locations, for the cleaning of the panels, for furnishing all hardware or other material necessary for the reinstallation of the sign structure, for the satisfactory removal of the existing footings, if necessary, including the excavation and backfill of the areas (old area and new area of the installation), disposal of excess materials, for new foundations for supports, for inspection and testing of welds, and for all other materials, equipment, tools, labor, and incidentals necessary to complete this item of work.

717-A Overhead Roadway Sign Structure No. _____ Renovation - per lump sum 717-B Overhead Roadway Sign Structure No. _____ Relocation - per lump sum STRUCTURES FOR TRAFFIC CONTROL DEVICES AND HIGHWAY LIGHTING 616

STRUCTURES FOR TRAFFIC CONTROL DEVICES AND HIGHWAY LIGHTING

718.01Description

This Section shall cover the design, fabrication, and construction of overhead roadway signs, luminaires, traffic signals, intelligent transportation systems, and traffic surveillance support structures. All designs and details shall be approved before actual fabrication of a structure is started. Within 30 days after the award of the contract, the Contractor shall notify the Project Manager by letter of the names, addresses and telephone numbers of all structural fabricators along with the fabricator's proposed fabrication schedule. The notification shall be furnished for all structural fabricators that are subcontractors to a structural fabricator.

718.02Materials

Materials shall comply in general with the requirements given in the applicable Sections of Division 800, MATERIALS. Particular structural material and fabrication requirements are given in Section 891,. Materials shall also comply with requirements that may be given on the plans. Concrete for foundations shall comply with the requirements of Section 501 for Class A concrete . Reinforcing steel shall meet the requirements of Section 502, Steel Reinforcement, and shall be Grade 60 {400} billet steel.

Overhead sign structures shall be constructed of steel only.

Unless otherwise shown on the plans, traffic signal poles shall be steel poles.

Unless otherwise shown on the plans, luminaire and surveillance poles may be constructed of steel, concrete, or aluminum.

Unless otherwise shown on the plans, Intelligent Transportation Systems (ITS) poles may be constructed of concrete, steel, or aluminum.

718.03Design

The details of pole foundations for Intelligent Transportation Systems (Section 729), Traffic Signals (Section 730) and Roadway Lighting (Section 750) are shown on the plans. When details of a structure or foundation are not shown on the Plans, or if the Contractor proposes alternate structure or foundation details, the Contractor shall submit complete designs and details. Geotechnical borings may be shown on the plans. These borings may not be representative of the actual conditions encountered throughout the project. The Contractor shall be responsible for any assumptions made from these borings. The Contractor shall obtain any additional geotechnical data that is necessary for determining the actual subsurface conditions.

All structures shall be designed in accordance with the requirements given in the AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals, 2009 Edition, and the requirements given in this Section. Fatigue importance factors shall be as follows:

STRUCTURES FOR TRAFFIC CONTROL DEVICES AND HIGHWAY LIGHTING 617

STRUCTURE FATIGUE IMPORTANCE FACTOR CATEGORY Strain Poles No Fatigue Mast Arm Poles/Lighting Poles/ITS Poles less than 45 ft. in height Category II with 25-year service life High Mast Poles/Sign Structures/Overhead Sign Bridges/Lighting Poles/ITS Poles 45 ft. or greater in height Category I Wind pressures shall be calculated in accordance with “Appendix C: Alternate Method for Wind Pressures”. Minimum design wind speed shall be 100 miles per hour {165 km/hr} for Mobile and Baldwin Counties and 80 miles per hour {130 km/hr} elsewhere in the State. The Combined Stress Ratio (CSR), shall be less than or equal to 0.9, for all load cases.

Foundations shall be located to avoid damaging existing underground installations and avoid conflicting with known future installations such as pipes, conduits, guardrail posts, lighting standards, etc. The design shall be sufficient to provide a minimum factor of safety of 2.0 against overturning and torsion induced displacement.

Drilled shaft foundations shall be placed only in undisturbed material or in fill made by controlled compaction. Drilled shaft foundations for cantilever structures shall be designed to resist the torsional effects of the wind loads.

Footings shall be placed only in undisturbed material or in fill areas constructed by controlled compaction. Footings for cantilever structures shall be designed to resist the torsional effects of the wind loads.

Prestressed concrete poles shall be installed by direct embedment in the ground. GFRP poles may be installed by direct embedment in the ground. The design and details of the direct embedment shall be submitted as Working Drawings for Structures. The required embedment is the responsibility of the contractor, however the minimum depth of embedment shall not be less than L/6, where L is the above ground length of the upright member or pole.

Pile foundations may be required in areas where the upper soil layers will not support a drilled shaft or spread footing. The foundations may be designed with steel piles or prestressed concrete piles. However, steel piles shall not be used in brackish or salt water locations in Mobile or Baldwin counties, or other locations with corrosive environments. Piles shall meet the requirements of Section 505, Piling.

Foundation anchor bolts for overhead highway sign structures and high mast lighting assemblies shall be Charpy V-Notch tested in accordance with the requirement provided in Section 891. Anchor bolts shall be a minimum one inch in diameter. Overhead sign structures with single pole uprights shall be anchored with at least eight anchor bolts in each base plate. Overhead sign structures with double pole (truss type) uprights shall be anchored with at least four anchor bolts in each base plate. Traffic signal poles and luminaire poles shall be anchored with at least four anchor bolts. High mast lighting assembly poles shall be anchored with at least eight anchor bolts. STRUCTURES FOR TRAFFIC CONTROL DEVICES AND HIGHWAY LIGHTING 618

All base plates shall be designed by calculating the bending moment about a line that is taken at the edge of the upright and is the shortest diagonal across the plate. The required thickness of the plate shall be based on the section modulus at the diagonal line using 60 % of the width of that line. The allowable stresses for a base plate shall be:  90 % of the yield strength of the base plate for plates that are designed for the yield moment of the upright or;  90 % of the allowable stresses for the Group loading for plates that are designed for the actual upright service load moment.

All overhead sign structures shall be supported by a reinforced concrete footing. The overhead portion of the structure shall be attached to the footing by means of base plates and anchor bolts. The vertical dead load deflection of cantilever sign structures shall not exceed L/120, where "L" is the cantilever length in inches {millimeters}. The vertical support for a cantilever structure shall be a round uniform diameter tube which has adequate moment of inertia, without additional reinforcement, to limit the dead load deflection of the arm, including the deflection caused by bending in the vertical support, to L/120 and to a maximum angular deflection of the centerline of the upright, at the top, in relation to the centerline at its base, of 1°40'. Horizontal trusses (span type) shall be limited to a vertical dead plus ice load deflection of L/240, where "L" is the total truss length center to center of supports in inches {millimeters}. A uniform camber, in accordance with the requirements of Section 9 of the AASHTO Sign Specifications , shall be provided for all horizontal portions of a structure. The use of full penetration circumferential welds on upright poles is not allowed. Horizontal trusses of triangular cross-section are not allowed. Flange plates that are used for splicing overhead truss chords and uprights shall be designed using the requirements given for BASE PLATES. Design and basic member shape once selected shall be used throughout the project. The detail drawings shall list all ASTM or AASHTO material specifications to be used for all the structural elements. Brackets shall be provided for the mounting of the required flat panel signs. These brackets shall permit mounting the sign faces at an angle of five (5) degrees from vertical except for louvered panels which shall be mounted vertically. This five degree angle shall be obtained by rotating the front top edge of the sign away from the vertical position. All brackets shall be of lengths sufficient for the heights of the signs being supported. Where required by the contract plans, tubular structures shall have electrical outlets provided on a front chord member and shall have hand holes within twelve inches of the base of vertical supports. If necessary, in order to comply with design requirements, compensation for loss in section shall be accomplished by reinforcement. Maintenance walkways, when required by the plans, shall be provided in front of the lower front chord. No part of the walkway shall be located so as to obstruct normal viewing of the lower portion of the sign.

The structural analysis of a pole shall be made at the base of the pole, and at every tenth point interval up the pole. The maximum deflection of the centerline at the top of the pole in relation to the centerline at its base, due to the moment load of the signal and support bracket, shall not exceed two and one half percent of the pole height. Calculations shall be submitted to verify this deflection. At intersections involving four traffic signal poles, each pole shall be designed equally for the most severe loading condition at the intersection. The pole base design shall conform to the following table of standard parameters if the maximum bending moment in the pole is less than or equal to 300 kip-ft.

STRUCTURES FOR TRAFFIC CONTROL DEVICES AND HIGHWAY LIGHTING 619

TRAFFIC SIGNAL POLE BASE STANDARD PARAMETERS Pole Type Moment Range (kip-ft.) Bolt Circle (Diameter) (inches) Bolt Diameter (inches) Bolt Quantity Base Plate Thickness (inches) P-120 Up to 120 20 2 4 2 P-170 121 – 170 20 2 6 2 P-225 171 – 225 22 2 6 2 P-300 226 – 300 26 2 8 2 If the bending moment is greater than 300 kip-ft, the bolt circle or bolt quantity, or both, shall be different from that given in the table for the standard parameters. If the proposed difference is in the diameter of the bolt circle, the diameter shall be a minimum of 27 inches.

High mast lighting assembly poles shall be supported by a reinforced concrete footing. A luminaire pole shall be analyzed at the base of the pole, at every tenth point interval up the pole, at section changes and at the points above and below each slip joint splice. Design calculations shall be submitted to verify that the maximum allowable deflections will not be exceeded.

Poles used for mounting Intelligent Transportation Systems, traffic surveillance devices, or other similar devices, shall be designed in accordance with the requirements given for luminaire poles and any additional criteria (i.e., more stringent deflection, vibration damping, etc.) provided on the contract plans.

718.04Construction Requirements

The overhead roadway sign structures, luminaire supports and traffic signal supports shall be constructed in accordance with the plans, specifications, foundation design calculations and approved shop drawings. All parts of a structure unit shall be assembled on the project and the Engineer shall be provided with adequate field erection details before permission will be given to erect the structure. Once the installation of structure is started, the work shall be diligently prosecuted until its completion.

Excavation for foundations shall conform to the neat lines shown on the plans. The Contractor shall inform the Project Manager when the excavation is complete, and no concrete shall be poured until the Project Manager has approved the excavation for each individual footing. The foundations may be cast directly against earth or cast with forms. When forms are used they shall be true to line and grade and securely braced in place. Both forms and ground, which will be in contact with the concrete, shall be thoroughly moistened before placing concrete. Forms shall not be removed until the concrete has thoroughly set. Tops of foundations shall be finished to the elevations shown on the plans. Ordinary surface finish shall be applied to the exposed surfaces of concrete. Exposed edges shall be chamfered. All concrete foundations and bases shall reach a compressive strength of 2400 psi {17 MPa} before any structures are installed thereon. All embedded items shall be installed securely and inspected by the Project Manager before concrete is poured.

Excavation shall be to the depth and diameter determined from the design calculations. The pole shall be placed in position and temporarily braced, prior to backfilling. The backfill material shall be limestone screenings or washed sand. The backfill shall be saturated with water to consolidate the backfill material during placement.

A temporary template shall be installed approximately 6 inches {155 mm} from the top and a permanent steel template shall be installed 6 inches {155 mm} from the bottom of anchor bolts so that the anchor bolts remain plumb after the placement of concrete. The template shall be fabricated with openings to facilitate the placement of concrete above and below the template. Care shall be taken to STRUCTURES FOR TRAFFIC CONTROL DEVICES AND HIGHWAY LIGHTING 620

ensure that the anchor bolt threads are not damaged prior to installation of the support structure. Out-of-position anchor bolts and anchor bolts greater than 1:40 out-of-plumb are cause for rejection of the base. Bending of the anchor bolts to straighten or move into position will not be permitted. The number and configuration of the nuts and washers required for anchor bolts shall be in accordance with the details shown on the plans. Anchor bolts for slip bases shall have the nuts installed in accordance with the requirements given in Section 710. Anchor bolts for non-slip bases shall have their top nuts tightened by the turn of the nut method as follows:

the base plate. The bottom of a leveling nut must be kept as close to the concrete base as practical and shall not be greater than 1 inch {25 mm} away from the top of the concrete base. A leveling nut shall be adjusted on the anchor bolt so that, after the installation of all plates and nuts, there is at least a 1/4 inch {6 mm} projection of the anchor bolt above the top or lock nut (when in its final position).

of the joint are in firm contact. This may be attained by a few impacts of an impact wrench or the full effort of a man using an ordinary spud wrench.

in full bearing on the base plate. If any gap exists between the nuts, washers and the base plate, a beveled washer shall be added to eliminate the gap. The beveled washer shall be stainless steel type 304, shall be the same diameter as the other washers, and shall be beveled as required to eliminate the gap between the nuts, washers and the base plate.

turn. There shall be no rotation of the leveling nut during top nut tightening.

of forty-eight hours after the nuts have been rotated the additional one third turn. Any nuts found loose shall be tightened in accordance with the above procedure.

Attention is directed to the fact that the structure design as well as shop drawings for the fabrication of the structure must be approved before actual fabrication of a structure is started. All parts of a structural unit shall be assembled on the project and the Engineer provided with adequate field erection details before permission will be given to erect the structure. The Contractor shall temporarily brace the structure as needed.

Strain and mast arm poles shall be installed with the proper vertical offset (or rake), as recommended by the manufacturers so as to assure a substantially vertical set when the load is applied. Threaded adjusting nuts shall be used to establish the "rake" in accordance with the requirements for the installation of leveling nuts on anchor bolts. The use of shims or other leveling devices will not be permitted. Hardware and fittings shall be installed as shown on the contract plans and approved shop drawings. Messenger cable supporting traffic signal heads shall not be sagged to a vertical distance greater than five percent of the length of the span between strain poles. Messenger cable supporting signal control cable only shall be sagged to a vertical distance not greater than two percent of the length of the span between strain poles. Tether cables shall not be sagged to a vertical distance greater than five percent of the length of the span between strain poles.

Extreme care shall be taken during installation of the luminaire assembly, Intelligent Transportation Systems equipment and surveillance devices to ensure that no damage occurs to these devices. Double nuts and washers shall be used to plumb the pole about its center axis if a twin bracket is used. When a single arm type is used, the back side of the pole shall be plumbed after the luminaire and surveillance devices and hardware have been installed, thus providing a slight rake from the traveled way.