6-328 SECTIO N 677 – OVERHEA D TRAFFI C SIGN SUPPORTS 677.0 1 DESCRIPTION . This work shall consist of furnishing and installing overhead traffic sign supports and removing and disposing of existing overhead traffic sign supports, including the concrete footings. 677.0 2 MATERIALS . Materials shall meet the req uirements of the following subsection s: Mortar, Type IV ................................ ................................ ................................ ......... 707.0 1(e) Aluminum Filled Silicone Sealant ................................ ................................ ............. 707.1 1 Bar Reinforcement ................................ ................................ ................................ .....713.01 Carbon Steel Bolts , Nuts, and Washers ................................ ................................ .....714.04 High -Strength Structural Bolts and Assemblies, 120 ksi ................................ ........... 714.05 Anchor Bolts for Traffic Signals, Lighting, and Overhead Signs .............................. 714.09 Steel Tubing ................................ ................................ ................................ ............... 714.11 Grounding Electrodes ................................ ................................ ................................ 752.1 1 The sign support shall be constructed of the material s shown on the Plans. The sign support design may be a cantilever structure or a multi -support structure (tubular beam, tri -chord, or box truss). All design details, quality of work , procedure, material s, etc., shall be in accordance with the AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals . Concrete shall conform to the requirements of Section 541 for Concrete, Class B. All welding shall be performed in accordance with the provisions of Section 506 . 677.0 3 GENERAL REQUIREMENTS . Overhead traffic sign supports shall be constructed in accordance with the details shown on the Plans. The design of mast arm and overhead sign support foundations shall be performed in accordance with MREI 10 -01. Prior to installation, the Contractor shall submit fabrication drawing s in accordance with Subsection
105.06 , which shall include a complete list of material s.
6-329 High -strength bolts, nuts, and washers shall be tensioned in accordance with Subsection 506.1 8. Field verification testing for direct tension indicators is not required. Anchor bolts shall be pre -tensioned in accordance with the followin g procedure:
a.Verify that the nuts can be turned onto the bolts past the elevation corresponding to the bottom of each in -place leveling nut and be backed off by the effort of one person on a 12 -inch long wrench or equivalent (i.e. without employing a p ipe extension on the wrench handle).
b.Clean and lubricate the exposed threads of all anchor bolts. Clean and lubricate the threads and bearing surfaces of all leveling nuts. Re -lubricate the exposed threads of the anchor bolts and the threads of the lev eling nuts if more than 24 hours have elapsed since earlier lubrication, or if the anchor bolts and leveling nuts have become wet since they were first lubricated.
c.Turn the leveling nuts onto the anchor bolts and align the nuts to the same elevation.
d.Place structural washers on top of the leveling nuts, with one washer corresponding to each anchor bolt. Install the base plate atop the leveling nuts and place structural washers on top of the base plate with one washer corresponding to eac h anchor bolt. Turn the top nuts onto the anchor bolts.
e.Tighten the top nuts to a snug -tight condition in a star pattern . Snug -tight is defined as the maximum nut rotation resulting from the full effort of one person on a 12 -inch long wrench or equival ent. A star tightening pattern is one in which the nuts on opposite or near -opposite sides of the bolt circle are successively tightened in a pattern resembling a star. For example, for an 8 -bolt circle with bolts sequentially numbered 1 to 8, tighten the nuts in the following bolt order: 1, 5, 7, 3, 8, 4, 6, 2.
f.Tighten leveling nuts to a snug -tight condition in a star pattern.
g.Before final tightening of the top nuts, mark the reference position of each top nut in a snug -tight condition with suitab le marking on one flat with a corresponding reference mark on the base plate at each bolt . Then incrementally turn the top nuts using a star pattern until achieving the required nut rotation specified below . Turn the nuts in at least two full tightening cy cles (passes) . After tightening, verify the nut rotation.
h.Top nuts for ASTM F1554 , Grade 55 anchor bolts shall be tightened to 1/3 turn beyond snug -tight condition for bolts less than or equal to 1 -1/2 inch diameter and 1/6 turn beyond snug -tight condi tion for bolts greater than 1 -1/2 inch diameter. The tolerance for nut rotation is + 20°. A beveled washer shall be used if the nut is not in firm contact with the base plate or if the outer face of the base plate is slope d steeper than 1:40 (V:H) . 6-330 Tightening requirements for all other bolted connections shall be specified on the fabrication drawing s. Concrete footings shall be backfilled by placing and compacting uniform layers of approved material not exceeding 6 inches in depth. Where aluminum allo ys come in contact with other material s, the contacting surfaces shall be separated with a fabric pad 1/8 inch in thickness or cleaned and thoroughly coated with an aluminum filled silicone sealant . The space between the top of the concrete footing and met al base of the support shall be sealed with a stainless steel wire cloth. The wire cloth shall be stainless steel standard grade, with a 1/4 inch maximum opening and a minimum wire diameter of No. 16 AWG with a 2 -inch lap. It shall be secured with 3/4 inch stainless steel banding after anchor bolts are fully tightened. Where existing overhead traffic sign supports are to be removed, the Contractor shall remove and dispose of the entire sign assembly, including concrete footings, to a depth of 18 inches below existing grade. Areas of ground disturbance shall be restored to the satisfaction of the Engineer. 677.0 4 GROUNDING . All posts used in overhead sign supports shall be grounded in accordance with Section 678 . 677.0 5 METHO D OF MEASUREMENT . The quantity of Overhead Traffic Sign Support, of the type specified, to be measured for payment will be the number of each installe d in the complete and accepted work . The quantity of Remove and Reset Overhead Traffic Sign Support to be measured for payment will be the number of each removed and reset in the complete and accepted work . The quantity of R emove Existing Overhead Sign Assembly of the type specified to be measured for payment will be the number of each assembly removed in the complete and accepted work . 677.0 6 BASIS OF PAYMENT . The accepted quantity of Overhead Traffic Sign Support, of the type specified, will be paid for at the Contract unit price for each . Payment will be full compensation for furnishing, transporting, handling, and installing the material s specified, including the concrete footings, excavation, and backfilling and for furnishing all labor, tools, equipment , and incidentals necessary to complete the work . 6-331 The accepted quantity of Remove and Reset Overhead Traffic Sign Support will be pai d for at the Contract unit price for each . Payment will be full compensation for removing the existing sign support, including all excavation, removal of the existing base as required, furnishing, placing, and compacting all necessary backfill, all necessa ry disconnections and modifications to existing wiring, construction of a new base as required, grading all areas disturbed by the work , turf establishment in those areas if turf establishment is not otherwise included in the Contract and for furnishing al l labor, tools, equipment , and incidentals necessary to complete the work . The accepted quantity of Remove Existing Overhead Sign Assembly of the type specified will be paid for at the Contract unit price per each . Payment will be full compensation for rem oving and disposing of assembly components, including concrete footings; for performing any excavation necessary; for restoring areas of ground disturbance; and for furnishing all labor, tools, equipment , and incidentals necessary to complete the work . Costs associated with providing traffic control or Flaggers for performing the work will be paid under the appropriate Contract item s. Payment will be made under: Pay Item Pay Unit
677.12 00 Overhead Traffic Sign Support, Cantilever ................................ .............. Each
677.13 00 Overhead Traffic Sign Support, Multi -Support ................................ ........ Each
677.22 00 Overhead Traffic Sign Support, Cantilever with Lighting ....................... Each
677.23 00 Overhead Traffic Sign Support, Multi -Support with Lighting ................. Each
677.25 00 Remove and Reset Overhead Traffic Sign Support ................................ ..Each
677.30 00 Remove Existing Overhead Sign Assembly, Cantilever .......................... Each
677.35 00 Remove Existing Overhead Sign Assembly, Multi -Support .................... Each
6-332 SECTION 678 – TRAFFIC SIGNALS
678.01 DESCRIPTION . This work shall consist of furnishing, installing, or modifying a traffic signal,
including all items necessary to provide a complete and operational system.
678.02 MATERIALS . Material s shall meet the requirements of the following subsections:
Granular Backfill for Structures ................................ ................................ ................. 704.08 Mortar, Type IV ................................ ................................ ................................ ......... 707.0 1(e) Aluminum Filled Silicone Sealant ................................ ................................ ............. 707.1 1 Paint for Traffic Control Signals ................................ ................................ ................ 708.06 Bar Reinforcement ................................ ................................ ................................ .....713.01 Carbon Steel Bolts, Nuts, and Washers ................................ ................................ .....714.04 High Strength Structural Bolts and Assemblies, 120 ksi ................................ ........... 714.05 Anchor Bolts for Signals, Lighting, and Overhead Signs ................................ .......... 714.09 Galvanizing ................................ ................................ ................................ ................ 726.0 6 Retroreflective Sheeting ................................ ................................ ............................. 750.0 4 Pedestal Posts and Bases ................................ ................................ ............................ 752.01 Traffic Signal As sembly ................................ ................................ ............................ 752.02 Traffic Signal Heads ................................ ................................ ................................ ..752.03 Traffic Signal Controllers and Cabinets ................................ ................................ ....752.04 Aerial Flashing Beacons ................................ ................................ ............................ 752.05 Electrical Conduit ................................ ................................ ................................ ......752.06 Traffic Signal Conductor Cable ................................ ................................ ................. 752.07 Vehicle Detectors ................................ ................................ ................................ .......752.08 Junction Boxes and Pull Boxes ................................ ................................ .................. 752.09 Accessible Pedestrian Signals ................................ ................................ .................... 752.10 Grounding Electrodes ................................ ................................ ................................ 752.11 Pan-Tilt-Zoom Camera ................................ ................................ .............................. 752.12 Emergency Vehicle Preemption System ................................ ................................ ....752.13 Concrete shall conform to the requirements of Section 541 for Concrete, Class HPA. Steel reinforcement shall conform to the requi rements of Section 507 .
678.03 GENERAL REQUIREMENTS . Traffic signals shall be installed as shown on the Plans and as
specified in the Contract. All design details, submittals, materials, installation, and wiring shall be performed in accordance with the applicable documents listed below, and other industry standards as appropriate.
Source: Vermont Standard Specifications for Construction, 2024 Edition. Pages 1102–1105 of 1,380.