605 METAL TRAFFIC BARRIERS

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605.01 DESCRIPTION.
Construct metal traffic barriers.
605.02 MATERIALS.
Refer to Sections 606, 609, 701, 705, 708, 709 and the following:
Brown Polyester Coating       465.03.02 (b)
Crusher Run Aggregate CR-6       901.01
Common Borrow       916.01.04
W Beam/Thrie Beam       918.01
Metal Posts       918.02
Traffic Barrier Hardware       918.03
Timber Posts       918.04
Wood Offset Blocks       918.04 grooved or routed
Wire Rope       918.05
Topsoil       920.01.01, 920.01.02
Subsoil       920.01.03, 920.01.04
Asphalt Millings or Grindings       Size of individual particles shall be less than 2 in. as determined visually
Rub Rail       A 36, Galvanized, A 123
Galvanizing Repair       465.03.05
Recycled Composite Offset Blocks       Grooved or routed
Reflective Delineators       As approved by Office of Traffic and Safety
605.03 CONSTRUCTION.
605.03.01 Post Installation.
(a) Install posts plumb to the specified depth. Drive posts unless directed otherwise, using a method that will not batter or distort the posts.
(b) If posts are not driven, dig holes of sufficient diameter to allow tamping of the backfill, and install the posts as follows.
When rock is encountered, drill a 12 in. diameter hole to the specified footing depth, or drill into the rock at least 20 in. depth, whichever is less.
When the 20 in. depth is reached prior to the specified footing depth, discontinue drilling and cut post to the appropriate length and paint the cut edge with galvanizing repair paint.
Backfill with approved common borrow, CR-6, or other material as directed. Place backfill in horizontal layers not exceeding 6 in. depth and thoroughly compact. Do not use concrete or grout material.
(c) When posts are installed into pavement, remove loose material and replace the pavement.
(d) When posts are installed into non-paved areas, remove unsuitable materials and restore areas to match adjacent turfgrass, asphalt millings or grindings, or crusher run aggregate CR-6.
(e) Align posts to within 1/4 in. of line and grade before installing rail or cable elements.
605.03.02 Rail Assembly. Install rail elements as specified. Ensure a smooth and continuous installation, with laps in the direction of traffic flow. Ensure that all bolts are tight.
605.03.03 Offset Blocks. When installing new traffic barrier W beam, use either wood or recycled composite offset blocks with grooves or router lines which prevent the blocks from rotating.
Do not mix different types of recycled composite blocks. Do not mix composite and wood blocks.
When an existing steel offset bracket is damaged, replace it with a steel bracket.
605.03.04 Brown Polyester Coated Traffic Barrier W Beam Using 6 Foot Post or 8 Foot Post. Ensure that components are padded and handled with fiber or cloth slings during loading, unloading, and installation.
Preserve the integrity of the polyester coating. If the polyester coating is chipped, scratched, blistered, or otherwise separated from the base metal, repair the damaged areas using the manufacturer's repair kit. Complete repairs or replace the damaged material.
605.03.05 W Beam Barrier Reflective Delineators. Install reflective delineators as specified.
605.03.06 Remove and Reset Existing Traffic Barrier. Replace severely corroded or damaged individual w-beam panels as directed.
When removing and resetting an entire run or a portion of a run of traffic barrier, replace the metal offset bracket with either wood or recycled composite offset blocks.
When removing and resetting an entire run, use 8 in. offset blocks. When removing and resetting only a portion of a run, use 6 in. offset blocks or match the offset blocks of the run as directed.
Ensure that the holes in the blocks match the holes in the existing posts. Move the posts at least 1 ft in either direction from the existing location.
When resetting the rail, measure the height of the rail to ensure that it conforms to the current height shown on the StandardsThe official Standards for Highway and Incidental Structures, maintained on the Administration website. The latest incorporated revisions issued on or before the date of advertisement of the Contract.. Unless otherwise directed, maintain the existing offset distance from the edge of the roadway.
After replacing w-beam panels, backfill disturbed areas with topsoil per Section 701, or crusher run aggregate CR-6, or asphalt millings or grindings, to restore grades in designated areas as specified or as directed.
In areas where more than 8 in. depth of topsoil is required, place subsoil per Section 701 and place 2 in. or 4 in. topsoil over the subsoil as specified or as directed. Immediately after placing topsoil, either perform Turfgrass Sod Establishment per Section 708, or perform Turfgrass Establishment and install Type A or Type E Soil Stabilization Matting per Section 709 over the seeded areas.
605.03.07 Remove and Reset Existing MedianThe portion of a divided highway separating the traveled ways for traffic in opposite directions. Traffic Barrier W Beam. Refer to 605.03.06.
605.03.08 End Treatments. Section 606.
605.03.09 Remove and Dispose of Existing Traffic Barrier. Assume all responsibility and make every effort to recycle or stockpile for noncontract use, all existing metal components of traffic barrier. Submit written certification, including date, time, materials, measurement and other pertinent information to the AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02. upon completion.
605.03.10 Removal and Disposal of Traffic Barrier W-Beam. After removal and disposal of traffic barrier, backfill disturbed areas with topsoil per Section 701, or crusher run aggregate CR-6, or asphalt millings or grindings, to restore grades in designated areas as specified or as directed.
In areas where more than 8 in. depth of topsoil is required, place subsoil per Section 701 and place 2 in. or 4 in. topsoil over the subsoil as specified or as directed. Immediately after placing topsoil, either perform Turfgrass Sod Establishment per Section 708, or perform Turfgrass Establishment per Section 705 and install Type A or Type E Soil Stabilization Matting per Section 709 over the seeded areas.
605.04 MEASUREMENT AND PAYMENT.
The payment will be full compensation for all driving, digging, drilling, offset blocks, restoration of grass, shoulder or paved areas, and for all material, labor, equipment, tools, incidentals, and fees necessary to complete the work.
Restoration of grassed and non-grassed areas with materials specified in Sections 606, 609, 701, 705, 708 and 709 will be incidental to the pertinent metal traffic barrier item, and will not be separately measured and paid for unless the aggregate or landscaping materials are included in the Schedule of Prices and plans indicate the locations and quantities of materials to be installed.
The cost of additional W beam panels which may be required for stiffening in locations where posts cannot be installed will be incidental to the pertinent W beam item.
605.04.01 Traffic Barrier W Beam Using 6 Foot Post or 8 Foot Post will be measured and paid for at the Contract unit price per linear foot.
605.04.02 Traffic Barrier W Beam Panel. When a bottom W beam panel is specified for the Traffic Barrier W Beam item it will be measured and paid for at the Contract unit price per linear foot.
605.04.03 Traffic Barrier W Beam MedianThe portion of a divided highway separating the traveled ways for traffic in opposite directions. Barrier will be measured and paid for at the Contract unit price per linear foot.
605.04.04 Traffic Barrier Thrie Beam will be measured and paid for at the Contract unit price per linear foot.
605.04.05 Replacing6 or 8 foot posts, installing additional 6 or 8 foot posts, splice joints, and replacing W beam panels will be measured and paid for at the pertinent Contract unit price.
605.04.06 Removal and Disposal of Existing Traffic Barrier W Beam will be measured and paid for at the Contract unit price per linear foot, including all costs required for disposal and certification. CertificationA document which verifies that the material and work complies with the applicable specifications and includes the actual test results to confirm the statement. The contents of the certification shall be on the Contractor's/vendor's/manufacturer's letterhead or approved document and shall be duly signed by a company officer. Certifications for metal products, when required, shall include a statement that the material was melted and manufactured in the United States except as provided in Section 165 of the Surface Transportation Assistance Act of 1982, as amended by Section 1041(a) and 1048(a) of the Intermodal Surface Transportation Efficiency Act of 1991 with regard to the furnishing and coating of iron and steel products. A nationwide waiver for this provision has been granted for pig iron and processed, pelletized, and reduced iron ore. of material recycled or stockpiled will be required prior to payment.
605.04.07 Remove and Reset Existing Traffic Barrier will be measured and paid for at the Contract unit price per linear foot.
605.04.08 Remove and Reset Existing MedianThe portion of a divided highway separating the traveled ways for traffic in opposite directions. Traffic Barrier W Beam will be measured and paid for at the Contract unit price per linear foot.
605.04.09  Traffic Barrier W Beam MedianThe portion of a divided highway separating the traveled ways for traffic in opposite directions. Barrier with Bottom Panel will be measured and paid for at the Contract unit price per linear foot.
605.04.10 Remove and Reset Existing MedianThe portion of a divided highway separating the traveled ways for traffic in opposite directions. Traffic Barrier W Beam with Bottom Panel will be measured and paid for at the Contract unit price per linear foot.
605.04.11 W Beam Barrier Reflective Delineators will be measured and paid for at the Contract unit price per each.
605.04.12 The application of fusion bonded brown polyester coating to traffic barrier W beam, and any special handling and touch up will not be measured but the cost will be incidental to the item to which the coating is applied.