THE STANDARD SPECIFICATIONS, SERIES 2001, ARE AMENDED BY THE FOLLOWING MODIFICATIONS AND ADDITIONS. THESE ARE SUPPLEMENTAL SPECIFICATIONS AND THEY SHALL PREVAIL OVER THOSE PUBLISHED IN THE STANDARD SPECIFICATIONS.

01048.01  Description.
This work shall consist of constructing high tension cable guardrail by furnishing and installing posts, cables, end anchors, and any special connections and fittings which may be required in the contract documents.

High tension cable guardrail shall:

1. Meet the requirements of NCHRP Report 350, Test Level 4 criteria.
2. Be accepted as a crashworthy device by the FHWA.
3. Exhibit a dynamic deflection for NCHRP Report 350 Test 3-11 of 8 feet (2.4 m) or less.

Approved products are listed in Materials I.M. 455.01.

01048.02 Materials.
The materials used for construction of high tension cable guardrail shall meet the manufacturer’s requirements. Concrete for concrete foundations for posts and end anchorages shall be Class C mix in accordance with Section 2403 of the Standard Specifications.

Spare parts kits for high tension cable guardrail shall consist of:

• An extra supply of TL-4 line posts (socketed-type), including post hardware and accessories (caps, reflective sheeting, straps, spacers, and socket covers). This supply shall include enough materials to complete a 300 foot installation.
• An extra supply of anchor posts (socketed-type), including post hardware and accessories (caps, reflective sheeting, straps, fittings, spacers, and socket covers). This supply shall include enough materials to complete one end anchor installation.
• Specialized tools necessary to maintain the guardrail, such as a spreader tool.

Spare parts kits shall not include a tension meter. The spare parts kit shall be delivered to the Contracting Authority’s nearest maintenance office.

01048.03 Construction.

A.  Installation of High Tension Cable Guardrail.
The Contractor shall install high tension cable guardrail according to the manufacturer's recommendations. Prior to construction, the Contractor shall provide the Engineer with three copies of the manufacturer’s most current product manuals covering installation and maintenance of the installation and signed certification statements for all materials to be incorporated into the installation in accordance with Materials I.M. 455.01.

The Contractor shall tension the cables according to the manufacturer's recommendations at the time of installation, then check and adjust the tension approximately three weeks after installation.

B.  Posts.
The posts shall be plumb and at the manufacturer’s recommended location, spacing, and elevation.

All posts shall be the “socketed” type and shall be installed in concrete foundations. Foundations shall be cast in place and constructed in accordance with Article 2505.03, B, 4 of the Standard Specifications. Dimensions and reinforcement shall be according to manufacturer’s recommendations except that foundation depth shall be at least 42 inches (1.1 m).

C.  End Anchors.
High tension cable guardrail installations shall incorporate one of the approved end anchors listed in Materials I.M. 455.01. Within each installation, end anchors and high tension cable guardrail shall be produced by the same manufacturer.

End anchors shall be constructed according to the manufacturer's recommendations for the site specific soil conditions. Soils testing required shall be incidental to the cable installation.

D.  Delineating High Tension Cable Guardrail.
High tension cable guardrail installations shall be delineated with retroreflective sheeting. The sheeting shall be applied to the last five posts at each end of an installation and throughout the remainder of the installation at a maximum spacing of 50 feet (15 m). The sheeting shall be Type III or IV retroreflective sheeting meeting the requirements of Article 4186.03 of the Standard Specifications. The sheeting shall provide at least 7 square inches (4500 mm²) of surface area when viewed from a line parallel to the roadway centerline and shall be attached near the top of the post in a manner recommended by the manufacturer. The sheeting shall be applied to that side of the post from which vehicle impacts are most likely. For installations where impacts are likely to occur from either side, the sheeting shall be applied to both sides of the post. The sheeting shall be yellow or white and shall be the same color as the adjacent edge line.

01048.04 Limitations.
In case of a discrepancy between these Specifications and the manufacturer's recommendations, these Specifications shall govern.

Concrete foundations for posts and end anchors may be subject to cable tensioning after 3 calendar days. This time requirement may be lengthened by the Engineer during cool weather.

Grading work, if required, shall be completed prior to installation of new guardrail.

When a roadway is open to traffic during construction, high tension cable guardrail installations shall be completed within 5 working days from the day the structure, barrier rail, pavement, shoulder, or whichever is the controlling item of work, is sufficiently completed to allow high tension cable guardrail installation. At locations where the proposed high tension cable guardrail installation does not interfere with the functioning of the existing guardrail, the existing guardrail shall not be removed until the high tension cable guardrail system is fully functional. High tension cable guardrail end anchors shall be delineated with a temporary traffic drum until the final end anchor is completed and the cables properly tensioned. Each installation exceeding the 5 calendar working day completion requirement will be subject to a contract price adjustment of $500 per working day. This price adjustment will be waived when the installation is designated as crossover protection only and no guardrail or concrete barrier has been removed.

When a roadway is closed to public traffic for construction, all high tension cable guardrail installations shall be completed before opening the road to traffic.

01048.05 Method of Measurement.

A.  High Tension Cable Guardrail.
The quantity of high tension cable guardrail will be the length shown in the contract documents.  The length will be calculated as the protection length, not including lengths of high tension cable guardrail end anchors.

B. High Tension Cable Guardrail End Anchors.
The Engineer will count the quantity of high tension cable guardrail end anchors constructed.

C. High Tension Cable Guardrail Spare Parts Kit.
The Engineer will count the number of spare parts kits delivered.

01048.06 BASIS OF PAYMENT.
Payment for high tension cable guardrail will include the furnishing of all materials, equipment, tools, and labor necessary to provide a complete installation of the high tension cable guardrail, including excavation and backfilling. However, excavation in unexpected rock will be paid for as extra work in accordance with Article 1109.03 of the Standard Specifications. Unexpected rock will be considered as rock encountered during excavation that was not visible from the roadway and was not indicated in the contract documents. The Engineer may adjust the payment for high tension cable guardrail in accordance with Article 2505.06, B of the Standard Specifications.

A. High Tension Cable Guardrail.
The Contractor will be paid the contract unit price per linear foot (meter) for the installation of high tension cable guardrail. All posts and accessories required by the manufacturer, as well as additional hardware and concrete, will be incidental to the item.

B. High Tension Cable Guardrail End Anchor.
The Contractor will be paid the contract unit price for each high tension cable guardrail end anchor. Grading required to meet the manufacturer's recommendations will be considered incidental to the high tension cable guardrail anchor.

C. High Tension Cable Guardrail Spare Parts Kit.
The Contractor will be paid the contract unit price for each spare parts kit delivered. Payment will be full compensation for delivering spare parts kits to the location identified in the contract documents.