SECTION 629 - VEHICULAR IMPACT ATTENUATORS
629.01 Description. This work consists of furnishing all materials, components and
accessories and installing impact attenuator systems meeting all of the requirements specified on the plans or in the contract documents, and assembled and constructed at the location(s) indicated on the plans or as established by the Engineer. This work shall also include the installation of median barrier end sections in accordance with the plans, specifications, and the manufacturer's recommendations.
629.02 Materials. Materials used in the construction of the vehicular impact attenuator
system shall all be new and shall conform to the applicable requirements of the respective section(s) of Section 700, as may be supplemented by requirements in other contract documents for the particular system installation. Approved impact attenuator systems shall meet standardized testing defined in NCHRP Report 350 or MASH. In addition, documentation from FHWA must accompany the devices, indicating that the devices meet the appropriate crash test criteria and can be used on the National Highway System (NHS). Prior to installation, the Contractor shall provide two copies of the manufacturer’s installation details to the Project Engineer. The Project Engineer shall keep one copy in project file and provide one copy to District Maintenance Engineer. The installation details shall be engineering drawings, a minimum of 11"x17" in size. Reflective adhesive sheeting with alternating black and yellow stripes (sloping downward at an angle of 45 degrees in the direction traffic is to pass) shall be required on the end of the attenuator section. The type of system installed shall be written on the device with a Permanent Marking Stick or some other means of permanent identification. The impact attenuators used must be as shown on the Department's APL. Replacement packages shall consist of spare parts of the expected type and number needed to repair one hit for each attenuator unit installed.
629.03 Construction Requirements . The system assembly shall be constructed in
accordance with the requirements for the fabrication and cons truction of the attenuator system as detailed on the plans and in the contract documents. For manufactured products specified, unless otherwise indicated in the co ntract, the system shall be fabricated and installed in accordance with the manufactur er's recommendation. In such case, the Contractor shall obtain the manufacturer's recommended installation instructions, including erection diagrams, and shall furnish the Engineer with a complete copy of such recommended installations and instructions. In the fabrication and construction of any vehicular impact attenuator system, sharp edges, projections, and any misfits of fabrication or construction shall be avoided. Installation of impact attenuators shall be accomplished by experienced workmen in accordance with the recommendations of the manufacturer. As a replacement supply, the Contractor shall furnish a spare parts package. The quantity and materials of this package will be that necessary to repair one hit for each attenuator unit installed. The Contractor shall use these parts to maintain the attenuator until release of maintenance. Upon completion of the work the replacement pack ages shall become the property of the Contractor. The median barrier end section and vehicular attenuator back-up wall shall be constructed in accordance with the plans, the manufacturer's recommendations, applicable provisions of Section 615 and other applicable provisions of the Standard Specifications.
629.04 Method of Measurement . Vehicular impact attenuators will be measured as a
unit for each complete attenuator installed and accepted. One replacement package shall be included in the bid price for each attenuator. Median barrier end sections and vehicular attenuator back-up wall will be measured as a unit for each complete and accepted section. Foundations for attenuators and median barrier end sections are considered parts of the respective units and will not be measured for separate payment.
629.05 Basis of Payment. Vehicular impact attenuators, median barrier end sections and
vehicular attenuator back-up wall will be paid for at the contract unit price per each. In the event an additional replacement package is required during the life of the contract, 25% of the lump sum price will be allowed to place the unit back in operation. Payment for the above listed units shall be full compensation for the work and materials required under this Section.
Vehicular Impact Attenuators in other states
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