614ELECTRICAL CONDUIT

New Hampshire Department of Transportation Standard Specifications – 2016 Description

1.1This work shall consist of furnishing, installing and testing conduit of the size and type specified, including sweeps, bends ,

joints, hangers, pull boxes, special fittings, plastic warning tape and other appurtenances, as shown on the plans or ordered. Sawed pavement, common structure excavation to the depth specified in 206. 4.1, bedding if required, and backf ill shall be included in this work. This work shall also include the disposal of discarded materials and the restoration of disturbed surfaces when not otherwise included under other items in the Contract. Materials

2.1Steel conduit and steel conduit for sleeves shall conform to ASTM A 53 Standard Weight and shall be galvanized unless

otherwise specified.

2.2Plastic Conduit.

2.2.1 Electrical plastic tubing (EPT) and electrical plastic conduit (EPC) including fittings and joint shall be made from polyvinyl-chloride (NEC 352) or polyethylene (NEC 353) and shall conform to NEMA TC 2 or NEMA TC 7. Conduit shall be marked in accordance with NEMA TC 2-6.1. 2.2.2 Only water tight fittings supplied or recommended by the manufacturer shall be used. 2.2.3 When the item description calls for Plastic Conduit (material is not specified) either PVC or polyethylene shall be furnished and shall meet the requirements of 2.2.1.

2.3Concrete for cast in place conduit encasement shall conform to Section 520, Class B. Precast concrete encased conduit will

not be permitted.

2.4Plastic warning tape shall be American Public Works Association standard 6” wide polyethylene color coded and marked in

accordance with the utility industry standards for marking underground utility lines.

2.5Concrete pull boxes, either precast or cast in place, shall be constructed using concrete conforming to Section 520, Class A

and designed for AASHTO H20 loading. Frame and cover castings shall be gray iron conforming to AASHTO M 105. Unless otherwise specified, all gray iron castings shall be Class 30. Covers shall be secured to the frame with two stainless steel hex head bolts conforming to ASTM A 240 Type 304. Pull boxes and covers shall be constructed as detailed on the plans.

2.6Molded pull boxes shall be either fiberglass -filled high density polyethylene (HDPE), fiber reinforced polyester mortar, or

fiberglass cloth reinforced polymer concrete, all with high impact resistance, ultraviolet stabilization tested per ASTM G53 and Chemical resistant tested per ASTM 543 section 7. The box and cover shall be designed for off roadway applications subject t o incidental, non-deliberate heavy vehicular traffic in accordance with the Western Underground Committee Guide 3.6 for non- concrete enclosures (WUC Guide 3.6). Boxes and covers shall be tested with the cover in place. 2.6.1 The cover shall withstand a vertical test load of 20,800 lb. applied at the center of the cover, by a 10” x 10” plate, with less than 1/2” deflection over 10 test cycles. The boxes shall withstand a vertical box wall test load of 20,800 lb. applied by a 10” x 10” plate with a 5” x 10” area centered on the long wall with no mo re than 1/4” deflection per foot of length of enclosure over 10 test cy cles. Boxes shall also withstand a lateral sidewall test load of 1,200 lb. per square foot applied by a plate 24 ” by the depth of the box, with no more than 1/4” deflection per foot of length of enclosure over 10 test cycles. Tested in accordance with Section 4.1 of WUC Guide 3.6. Permanent deflection of any surface shall not exceed 10 percent of the maximum allowable static test load deflection. 2.6.2 Enclosures shall be designed and suitable for installation and use through a temperature range -40º F to 195º F 2.6.3 Covers, boxes and extensions shall meet the acceptance criteria in accordance with Section 5.3 of WUC Guide 3.6. A spray or paint covering shall not be used to achieve the required nonflamability. 2.6.4 Boxes and extensions shall have adequate soil bearing surface to prevent settling in any soil, when tested in accordance with Section 4.1 of WUC Guide 3.6. 2.6.5 Covers and extensions shall be interchangeable with other boxes of the same material type an d size manufactured to WUC Guide 3.6. 2.6.6 Any point on the covers shall withstand a 70 lb(f)-ft. impact administered with a 12 lb. weight using a “ C” TUP (ASTM D-2444) without puncturing or splitting. The test shall be performed with the cover resting upon a flat, rigid surface such as concrete or a 1” steel plate. 2.6.7 Cover surface shall provide a minimum coefficient of friction of 0.50. Covers shall be secured to box with two hex- head stainless steel bolts conforming to ASTM A 240 Type 304. Bolts shall be self -retaining and shall withs tand a minimum of

New Hampshire Department of Transportation Standard Specifications – 2016 70 lb(f)-ft. torque and have a minimum of 750 lbs straight pull out strength. Nuts shall be floating, replaceable and in a nut cavity which is free draining and shall provide a minimum of 1/2” movement from the center of the nut. 2.6.8 A Certificate of Compliance that the enclosure meets the above requirements when tested in accordance the Western Underground Committee Guide 3.6 testing procedures by a nationally recognized independent testing laboratory shall be provided. Construction Requirements

3.1General.

3.1.1 Installations within the limits of the traveled way and shoulders, whether paved or unpaved, shall be constructed with Schedule 80 plastic conduit (EPC), rigid steel conduit, or concrete encased Schedule 40 plastic conduit (EPC). 3.1.2 Installations beyond the limits of the traveled way and shoulders shall be constructed with Schedule 80 plastic conduit (EPC), Schedule 40 plastic conduit (EPC), or rigid steel conduit. These materials may also be used under sidewalks and parking lots subject to incidental heavy vehicular activity. 3.1.3 Sawed pavement shall conform to 628.3.4.

3.2Bedding.

When conduit is installed within traveled ways, shoulders, sidewalks and parking areas, the backfill shall be placed to 6” above the conduit or encasement and compacted by pneumatic tampers, vibratory compactors, or other approved means. Additional backfill shall be placed in layers not greater than 6”.

3.3Laying.

3.3.1 Conduit shall be laid to a pitch of not less than 3” per 100 feet. 3.3.2 All conduit lines located under pavement shall be installed in a straight line. Field bends required in other areas shall be made with an approved conduit bender. N ot more than four 90 degree bends or equivalent (360 degree total) shall be used on a continuous conduit line. Bending radius shall not be less than 30 ft. unless otherwise directed. Bends in conduit entering pull boxes, light pole bases, signal and meter pedestal bases, transformer pads, signal controller bases and at risers shall be made with manufactured electrical standard elbows. 3.3.3 All conduit connections shall be waterproof and conform to NEMA TC 2- 3.4. When conduit of one material is to be joined to an existing conduit of another material, weatherproof adapters manufactured for the purpose shall be used. Waterproofing and sealing compounds containing bituminous material shall not be used. 3.3.4 When conduits are encased in concrete, concrete cover around ducts shall be a minimum of 3” with a minimum separation of 1-1/2” between ducts unless otherwise specified or ordered. After the initial set, the concrete shall be protected from the air and sun. Fill shall not be placed over the conduit until authorized by the Engineer. 3.3.5 Conduit risers installed on poles or other structures shall extend a minimum of 10 ft. above the elbow and be of a type and total height to meet utility company requirements. Conduits shall be attached with an approved support strap. A suitable plug shall be installed in the end of the conduit riser. 3.3.6 When ordered, conduit shall be placed under existing pavement by approved jacking or drilling methods which do not disturb the pavement. Pavement shall not be distu rbed without the written permission of the Engineer. Jacking and drilling pits shall be kept 2 ft. clear of the edge of pavement. 3.3.7 When so directed, and whenever a continuous traffic signal conduit line is greater than 90 ft., additional pull boxes shall be installed. Cable splices shall not be made in these boxes without permission. 3.3.8 A minimum of 3 ft. of space shall be left between the ends of conduit runs where there may be a future junction. When conduit is installed which does not terminate in a pull box, equipment base or similar type foundation, a witness marker consisting of a No. 5 re-bar of sufficient length to allow for the top of the marker to be set flush with the final grade shall be placed vertically at each end of such buried conduit. 3.3.9 Unless otherwise directed, a 14 gauge galvanized steel pull wire or plastic/nylon rope having a minimum tensile strength of 200 lb, shall be placed in all conduit runs. At least 24” of wire or rope shall be left coiled at each end of the conduit. 3.3.10 Brackets or spacers/separators for hanging and/or bundling ducts shall be as shown in the plans or approved by the Engineer. 3.3.11 Various Size Duct Conduit. The configuration of the multiple sized conduits shall be in accordance with the details shown in the plans.

New Hampshire Department of Transportation Standard Specifications – 2016

3.4Backfilling.

3.4.1 All backfill material adjacent to conduit shall be approved material. Backfill material shall be free from hard lumps or clods larger than 3” in diameter and free from rocks and stumps. Backfill within the pavement structure shall be of the same type material and match the depths encountered. 3.4.2 When conduit is installed beyond traveled ways and shoulders, and outside of areas such as sidewalks and parking lots, the backfill shall be placed to 6” above the conduit and compacted by pneumatic tampers, vibratory compactors, or other approved means. The remainder of the backfill material shall then be placed and compacted by an approved method. 3.4.3 When conduit is installed within traveled ways, shoulders, s idewalks and parking areas, the backfill shall be placed to 6” above the conduit or encasement and compacted by pneumatic tampers, vibratory compactors, or other approved means. Additional backfill shall be placed in layers not greater than 6”. 3.4.4 Bituminous or Portland cement concrete pavement removed to excavate the trench shall be replaced with hot bituminous pavement conforming to the requirements of Section 401 unless otherwise directed. Pavement shall be placed in thoroughly compacted layers of not more than 2” to give a total thickness equal to that of the existing pavement. All backfill shall be compacted to not less than 95 percent of maximum density as determined by AASHTO T 99. 3.4.5 Conduits provided for f uture use shall have suitable plugs installed at each end. Conduit ends shall not be backfilled until reference measurements are made by the Engineer. 3.4.6 A plastic warning tape shall be installed over all conduits at approximately 12” below final grade.

3.5Testing.

3.5.1 After the trench has been backfilled, excluding pavement if applicable, the Contractor, in the presence of the Engineer, shall test the installation by pushing through the entire length of the conduit line a device with a diameter not smaller than 1/4 ” less than the inside diameter of the conduit. All obstructions including stones, dirt, and the like, shall be removed. Broken or other unsatisfactory conduits shall be replaced at no expense to the Department. 3.5.2 When ordered, existing conduit to be incorporated into a new system shall be cleaned with a mandrel and blown out with compressed air.

3.6Pull Boxes.

3.6.1 Pull boxes within the limits of the traveled way, shoulders, whether paved or unpaved, parking lots, adjacent to slope curb, and within 10 ft. of the edge of pavement shall be concrete and installed as shown on the plans and specified herein. 3.6.2 Pull boxes outside the limits of 3.6.1 shall be concrete or molded and installed as shown on the plans and specified herein. 3.6.3 All pull boxes shall be placed on a minimum of 6” of Granular Backfill conforming to 209 .2.1 extending at least 4 ” beyond the outside of the pull box compacted to not less than 95 percent of maximum density as determined by AASHTO T 99. With the cover installed, soil shall be backfilled and compacted around the box. At final installation the box and cover sha ll be flush with finished grade. 3.6.4 Pullbox covers shall have a recessed logo indicating the type of service enclosed. 3.6.5 An approved 2” galvanized “ J” hook shall be installed as directed in pull boxes designated to be used for traffic signal circuits. Method of Measurement

4.1Conduit will be measured by the linear foot of the specified type, size and number of ducts of the size required, to the nearest

0.1 of a foot. Multiduct conduit will be measured as a single run down the centerline of the conduit bundle. 4.1.1 When a conduit is connected to a foundation for a signal pole, control cabinet pole, or l ight pole, measurement will be made only to 3 ft . from the center of the base, measured horizontally. The limit of measurement where conduit is joined to previously existing conduit will be at the junction of the two conduits.

4.2Pull boxes will be measured by each, but will not be deducted from the length of the conduit.

Basis of Payment

5.1The accepted quantities of conduit will be paid for at the Contract unit price per linear foot of the type, size and number o f

ducts specified complete in place, including brackets/spacers, sawed pavement, common structure excavation to the depth specified in 206.4.1, bedding if required, and backfill, with the following exceptions:

New Hampshire Department of Transportation Standard Specifications – 2016 5.1.1 All rock structure excavation, any common str ucture excavation below the depth specified in 206. 4.1, and any excavation of unsuitable material required below the conduit will be paid for under Section 2 06. 5.1.2 New material ordered for use as backfill below the subgrade to replace rock structure or unsuitable excavation will be paid for under Section 209. 5.1.3 Hot bituminous pavement required in 3.4.4 will be pa id under Section 403 . If the item of 403 is not included in the Contract, this work will be paid as provided in 109.04.

5.2The accepted quantities of pull boxes of the type specified will be paid for at the Contract unit price per each.

5.2.1 No extra payment will be made for material specified in 3.6.3. Pay items and units: . A B C D E Linear Foot A Conduit Type 1 Concrete Encased 2 Open 3 Steel Conduit 8 Relaying Conduit B Size (round up to nearest whole number) 9 9” and over Duct 0 Various Sizes in Multi Duct C Number of Ducts . 5 Pull Boxes Each B Box Type 1 Concrete 1 14” 2 18” 2 Molded 2 13 by 24” 3 17 by 30” . 7 Plastic Conduit Linear Foot B Size (round to nearest whole number) 0 Various Sizes in Multi Duct C Number of Ducts (10 and over use 0) D Schedule 4 Schedule 40 8 Schedule 80 E Plastic Conduit Material 1 PVC 2 Polyethylene

New Hampshire Department of Transportation Standard Specifications – 2016

Description

This work shall consist of furnishing, erecting, relocating or removing traffic signs and sign supports as shown on the plans or

as ordered.

1.2Sign Types.

1.2.1 Traffic Signs Type A and Type AA shall be extruded aluminum plank traffic signs with retroreflective sheeting background and retroreflectorized demountable cut -out copy. Type A shall include W -beam mounts and hard ware as shown on the plans. 1.2.2 Traffic Signs Type B and Type BB shall be flat sheet aluminum signs with retroreflective sheeting background and retroreflectorized cut-out copy or overlay film. Type B shall include aluminum tube mounts or steel “ U” post mounts or as shown on the plans. 1.2.3 Traffic Signs Type C and Type CC shall be flat sheet aluminum signs with retroreflective sheeting background and non-embossed copy unless otherwise shown on plans. Type C signs shall include aluminum tube mounts or steel “ U” post mounts or as shown on the plans. Materials

All parts used in constructing signs shall be designed to withstand a wind loading of 35 pounds per square foot on the sign

surface, unless otherwise noted on the plans.

Plank Signs.

2.2.1 Extruded aluminum planks shall be of the butt type, 6 or 12” wide and of the lengths indicated on the plans. Edge moldings are optional and if furnished shall match the panels and shall have a natural aluminum finish. Aluminum panels shal l conform to the requirements of ASTM B 221, Alloy 6061-T6. Aluminum molding may be of T5 or T6 temper.

Sheet Signs.

2.3.1 Flat aluminum sheets for sheet signs shall be one piece and con form to ASTM B 209 , Alloy 6061-T6 or Alloy 5052- H38. The minimum thickness of the sheets up to 36” wide shall be 0.080” Signs greater than 36” shall be a minimum of 0.100”. 2.3.2 Plywood sheet signs shall be standard form (BB grade or better), minimum 0.5”, exterior type with both faces of medium density overlay (MDO) as described in Voluntary Product Standard “ PS-1-95 Construction and Industrial Plywood”, National Institute of Standards & Technology. The edges of the plywood signs shall be sealed by painting them with a sealer.

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Vertical Supports.

2.5.1 Steel posts shall conform to ASTM A 36 or ASTM A 572 and unless otherwise shown on the plans, shall be galvanized in accordance with AASHTO M 111 (ASTM A 123). 2.5.1.1 The total maximum weight of steel posts below the hinges of a breakaway support system shall not exceed 45 pounds per foot when 2 posts are to be placed within 7 ft. of each other. 2.5.1.2 Overhead traffic sign structures shall be galvanized steel designed in accordance with 3.4.1. 2.5.2 Aluminum posts for non- breakaway supports shall be of a standard shape aluminum tubing confor ming to ASTM B 221, Alloy 6061-T6 or 6063-T6, as shown on the plans. The wall thickness shall be a minimum of 1/8” and a maximum of 3/16”. 2.5.2.1 Aluminum posts for use with breakaway support systems shall conform to ASTM B 429, Alloy 6061- T6 or 6063- T6, Schedule 40, as shown on the plans. 2.5.3 Steel “ U” posts shall be rail steel conforming to the requirements of ASTM A 499, Grade 60 or ASTM A 576, Grade 1070-1080, minimum yields trength of 60,000 psi. Posts shall be galvani zed in accordance with AASHTO M 111. The weight per foot shall be a minimum of 2 -1/2 lb. and a maximum of 3 lb. The posts shall have 3/8 ” holes drilled or punched, before painting, along the center line of the web. The holes shall begin 1 ” from the top of post and continue at 1” centers for the entire length of the post.

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2.7Hardware.

2.7.1 Hardware for signs shall conform to the NHDOT Standard Plans.