664Impact Attenuators

664.1-DESCRIPTION: This work shall consist of the furnishing, assembly, and installation of Impact Attenuators in accordance with these Specifications, Plans, device manufacturer specifications and Installation Drawings, or as established by the Engineer. All work shall be done in a uniform, workmanlike manner. All details not specified or not shown on the Plans shall conform to the details and requirements set forth in the following specifications and publications:

Roadside Design Guide, latest issue including revisions, hereinafter referred to in this Section as the RDG 664.2-MATERIALS: Materials furnished shall be of new stock, shall be the product of reputable manufacturers, shall conform to the Specifications, and shall meet the approval of the Engineer. Materials shall conform to the general requirements of subsection 715.41 and the requirements of the following subsections: MATERIALS SUBSECTION Class 1 Impact Attenuator 715.41.1 Class 2 Impact Attenuator 715.41.2 Approved devices are listed on the Division Approved Products List (APL) for Impact Attenuators – MASH. The design width and tapered or non -tapered characteristics of each device are noted on the APL. In cases where a device with tapered sides would normally be required to properly shield an object, the Contractor may at their option choose to provide and install a Class 1 device with non-tapered sides and a rigid tapered transition from the device to the obstacle being shielded, provided specific criteria are met. Criteria to be met and additional drawings to be included with the Contractor’s Installation Drawing submittal are provided in Appendix A of WVDOH Design Directive 666, Impact Attenuators. In addition, the transition shall be MASH compliant at the same Test Level as is required for the Impact Attenuator. The Contractor shall provide documentation sufficient in the WVDOH’s determination to support this upon request. 664.3-INSTALLATION DRAWINGS: The Contractor shall submit eight (8) sets of installation drawings for all permanent Class 1 and 2 Impact Attenuators for approval prior to installation. Drawings shall be site specific providing an accurate representation of the obstacle being shi elded, approach area, concrete pads and backups to be installed, as well as any required transitions. The drawings shall clearly specify required concrete strength, reinforcement requirements, anchoring requirements, connection to existing barrier requirements, as well as the device brand name and model number. The drawings shall include assembly details. The installation drawings shall also include all applicable details previously described for any rigid transition to be used to achieve a greater width as allowed for in Section 664.2. Installation drawings will be reviewed and, if approved, stamped and returned to the Contractor. Multiple devices of the same design to be installed under identical conditions may be represented by one (1) set of drawings. 699 664.4-CONSTRUCTION METHODS: All Impact Attenuators shall be placed, assembled, and installed in accordance with the manufacturer specifications and Installation Drawings. Class 1 devices shall be in stalled on a concrete foundation, this being a bridge deck or concrete pad fully designed and specified by the manufacturer. If the manufacturer Installation Drawings require a concrete block backup separate from any concrete backup structure constructed under other provisions of the Specifications, the backup shall be constructed by the Contractor in accordance with the Installation Drawing requirements. If adhesive type anchors are required to anchor the device, the Contractor shall not fully tighten the device anchors until after the adhesive has fully cured. When installing a Class 2 Impact Attenuator, the Contractor shall assess the need for soil plates in accordance with the recommendations of the manufacturer and utilize such if recommended. Soil plates shall be utilized regardless of manufacturer recommendations if directed by the Engineer. The nose or impact head of all devices shall be delineated with a striped, retroreflective panel or decal. The retroreflective material shall meet the requirements for fluorescent yellow Type ASTM-XI retroreflective sheeting, as provided elsewhere within the Specifications. The design of the panel or decal shall be in substantial conformance with the XS -15 design provided in the WVDOH Sign Fabrication Details manual, except all right shoulder mounted devices shall have all stripes sloping down and to the left, and all left shoulder mounted devices shall have all stripes sloping down and to the right. 664.5-METHOD OF MEASUREMENT: Attenuators will be measured as a unit, complete and in place. 664.6-BASIS OF PAYMENT: The quantities, determined as provided above, shall be paid for at the contract unit price for the items listed below, which prices and payment shall be full compensation for furnishing all the materials and doing all work prescribed in a workmanlike and a cceptable manner, including all tools, equipment, supplies, and incidentals necessary to complete. All incidental work and materials for which no basis of payment is provided will be considered as completely covered by the prices bid for the items included in the contract. 664.7-PAY ITEMS: ITEM DESCRIPTION UNIT 664015-* Impact Attenuator, C-1, TL-2, “Design Width in Inches” Each 664016-* Impact Attenuator, C-1, TL-2, 36+” Each 664020-* Impact Attenuator, C-1, TL-3, “Design Width in Inches” Each 664021-* Impact Attenuator, C-1, TL-3, 36+” Each 664025-* Impact Attenuator, C-2, TL-3, 24” Each * Sequence number C = Class Number shall be designated as C-1 or C-2 TL = MASH Test Level shall be designated as TL-2 or TL-3 “Design Width in Inches” shall be 24”, 30”, or 36” 700