612 CABLE BARRIER SYSTEM

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612.01 DESCRIPTION
Furnish and install a high-tension cable barrier system using pre-stretched cables, cable barrier transition to W-beam, and end-anchor terminal sections.
612.02 MATERIALS
Refer to 605.02, 701.02, 705.02, 708.02, 709.02 and the following:
Cable Barrier System       As approved
Barricades for Maintenance of Traffic       104.13
Concrete Mix 2 and 6       902.10
Common Borrow       916.01
Traffic Barriers       Section 918
Reflective Delineator Sheeting, Type IV       950.03
Line Post and End-Anchor Terminal Footings        As specified by the manufacturer
612.03 CONSTRUCTION
612.03.01 Site Information. Supply the cable barrier manufacturer with soil information and investigation needed to design the cable system line post and end-anchor footings, including any soil borings that have been provided for the project.
612.03.02 Cable Barrier System. Provide a cable barrier system that has a maximum dynamic deflection upon vehicular impact not to exceed 9 ft, and which does not encroach on the opposing traffic shoulder or place a roadside obstruction in the deflection zone. At locations where the dynamic deflection distance is not achievable, decrease the post spacing according to the manufacturer’s engineered calculations to not exceed the required deflection.
612.03.03 Working drawings and calculations. Provide working drawings and calculations for the design of line post and end-anchor footings, based on the site-specific soil conditions. Calculate the deflection and post spacing according to the manufacturer’s recommendations, signed by a licensed engineer in the State of Maryland, and submit for Administration’s review as specified in TC-4.01.
612.03.04 Site Preparation. Provide construction stakeout for the line posts and end-anchor terminals. Notify the Engineer of any potential conflicts with underground utilities or drainage before construction. Complete clearing, grubbing, and final grading before installation of each section of cable barrier line post footings, transitions, or end-anchor terminal systems. If indicated on the Plans, perform excavation, grading, and paving for cable barrier maintenance pavement prior to excavation or drilling for post footings.
612.03.05 Grading Adjustment. When grading adjustment is required for installation of cable barriers, adjust the grading using topsoil, crusher run aggregate CR-6, asphalt millings or grindings, subsoil, common borrow, or other approved material as specified in 605.03.04(a), (b), and (c).
612.03.06 Post Installation. Excavate for and install cast-in-place, reinforced concrete footings for line posts at the manufacturer’s recommended location, spacing, and elevation. Install footing reinforcing steel as required in the approved shop drawings. Place the concrete and install sockets as required by the manufacturer, keeping the top of the footing flush with the final grade. Install line posts. Space the specified posts according to the manufacturer’s recommendations. Set posts plumb and in a straight line.
612.03.07 Cable Installation. Install cable barrier system cables according to the manufacturer’s details and specifications. Position rigging screws such that there is no interference with posts or other rigging screws, unless recommended by the manufacturer. The strength at the splice must be equal to or greater than the strength of the cable itself. If required by the manufacturer, install post caps according to the manufacturer’s recommendations.
612.03.08 Cable Tension. Tension each cable according to the manufacturer’s specifications. Provide a calibrated tension meter with a serial number and a current Certificate of Calibration from a National Institute of Standards and Testing accredited laboratory to remain with the Engineer at project completion.
Provide a recommended tension chart from the manufacturer for their system with the base condition temperature. The chart shall be indexed using cable temperature, in degrees Fahrenheit, as the independent variable and tension, in pounds, as the dependent variable.
Provide a certified tester to perform tension tests on the system. Retest the cable tension according to the manufacturer’s specifications 14 to 21 calendar days after the first test. Re-tension the cable when the test reading is less than the manufacturer’s recommendations for the given temperature. Re-tension the cables to the manufacturer’s specifications by successively reading tension measurements at every rigging screw or turnbuckle. Repeat the testing and re-tension the cables according to the manufacturer’s specifications until the manufacturer certifies the full cable system.
Maintain a tension log showing project name, time and date, weather conditions, segment, cable temperature, test location, and tension reading. Deliver the log, along with the manufacturer's recommended tension chart, to the Engineer prior to acceptance of the cable barrier system.
612.03.09 End-Anchor Terminals. Excavate for the end-anchor terminals in natural, undisturbed ground, to the size and shape required by the manufacturer, based on soil types and ground conditions. If over excavation is unavoidable, as verified by the Engineer prior to installation of the concrete, the sides of the excavation must be vertical and use additional concrete to fill the excavated area completely at no additional cost to the Administration.
Install cast-in-place, reinforced concrete end-anchor terminals according to the manufacturer’s recommendations and approved shop drawings. Complete the installation by the end of the same working day. Do not leave any incomplete end-anchor terminal overnight or unprotected when the roadway is under traffic.
612.03.10 Transition to W-beam. Install cable barrier to W-beam transition according to the manufacturer’s recommendations. Install W-beam barrier as specified in 605.03.
612.03.11 Reflective Delineators. Install reflective delineator sheeting every 50 ft of installed cable barrier, every 20 ft on horizontal curves with a radius less than 1300 ft, and on posts installed as part of an end anchor terminal or cable barrier transition to W-beam. Ensure that the delineator sheeting is visible from both directions of traffic unless otherwise shown on the Plans. Attach the delineator reflective sheeting to the post cap, if provided, or near the top of the post according to the manufacturer’s recommendations.
612.04 MEASUREMENT AND PAYMENT
The payment will be full compensation for stakeout; utility coordination; installation of all line posts, concrete footings, sockets, wire rope, fittings, and reflective delineators; excavation, backfill, compaction, and shoulder build-up; tensioning; tension meter; restoration of grass, shoulder, or paved areas and other repairs; and for all materials, labor, equipment, tools, working drawings and calculations, additional soil investigation, and incidentals necessary to complete the work.
612.04.01 Any additional soil information gathering (including, but not limited to, test pits, borings, or laboratory testing) are incidental to construction of the cable barrier system.
612.04.02 Cable Barrier System will be measured and paid for at the Contract unit price per linear foot along the centerline of the system.
612.04.03 Grading adjustment using topsoil and subsoil will be measured and paid for at the Contract unit price as specified in 701.04.
612.04.04 Type A Soil Stabilization Matting or Type E Soil Stabilization Matting will be measured and paid for at the Contract unit price per square yard.
612.04.05 Grading adjustment using CR-6 crusher run aggregate, or asphalt millings or grindings, will be measured and paid for at the Contract unit price per square yard, per ton, or as specified for the pertinent items. The payment will also include full compensation for furnishing, adjusting, and compacting embankment or aggregate material.
612.04.06 Grading adjustment using common borrow will be measured and paid for at the Contract unit price per cubic yard as specified in 203.04.
612.04.07 Grading adjustment using other approved materials will be measured and paid for as pertinent items.
612.04.08 Turfgrass Sod Establishment or Turfgrass Establishment will be measured and paid for at the Contract unit price per square yard.
612.04.09 Cable Barrier Transition to W-beam will be measured and paid for at the Contract unit price per each.
612.04.10 Cable Barrier End-Anchor Terminal Section Assembly will be measured and paid for at the Contract unit price per each.
612.04.11 Any damage to paved areas due to construction activities will be repaired at no cost to the Administration.