627-r-546 cable barrier system




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10-01-12

627-R-546 CABLE BARRIER SYSTEM



(Revised 06-21-12)
The Standard Specifications are revised as follows:
SECTION 627, BEGIN LINE 1, DELETE AND INSERT AS FOLLOWS:

SECTION 627 – BLANKCABLE BARRIER SYSTEM
627.01 Description

This work shall consist of furnishing and installing a high-tension cable barrier system in accordance with 105.03.
627.02 General Requirements

The cable barrier system shall consist of 4 pre-stretched, individual wire ropes in tension between safety terminals and held in position by intermediate line posts. The system may incorporate single or multiple anchor foundations for the safety terminals to terminate the 4 wire ropes. The system shall be selected from the Department’s list of approved Cable Barrier Systems. The Contractor shall use the selected system for the entire contract. The selected system shall be installed in accordance with the manufacturer’s recommendations except as modified by these specifications.
The Department will make geotechnical information available for the approximate locations of the safety terminals and representative locations of the intermediate line posts. The Contractor shall be responsible for obtaining any additional geotechnical information required by the cable barrier system manufacturer to complete design of line post and safety terminal foundations or other components of the system.
The Contractor shall provide the following to the Engineer a minimum of 14 days prior to installation of the system:
(a) A copy of the FHWA acceptance letter for the cable barrier system.
(b) Two copies of the manufacturer’s product brochure, specifications and installation and maintenance manuals.
(c) Documentation that the Contractor’s work force on the project has received training by the manufacturer in the proper installation of the system, including safety terminals, intermediate line posts, cables and tensioning of cables.
(d) Four copies of erection drawings clearly depicting installation details, including safety terminals, terminal transitions, intermediate line posts and cables.
(e) A copy of the design drawings and calculations for safety terminal and intermediate line post foundations for all soil conditions on the project. Design drawings and calculations shall be stamped by a professional engineer. The calculations shall include a geotechnical and structural analysis for each soil condition encountered.
(f) The geotechnical analysis shall verify adequate uplift capacity, as well as check for horizontal deflection, shear capacity and bending moment capacity. When cables are to be anchored in multiple foundations to the analysis shall check the deflection and capacity as a group. The structural analysis will include a check of the structural capacity of each foundation and the anchorage system used to transfer the forces from the cables to the foundations.
Safety terminal foundations shall at a minimum be designed to resist movement in the soil due to system tensioning and impacts to the system at the NCHRP 350 test level specified. Design of the safety terminal foundations shall include a factor of safety of 1.5 for overturning and pullout.
If all cables are to be anchored to a single foundation, the design of safety terminal foundations and cable connections shall be based on a minimum total equivalent horizontal static load of 50,000 lbf and the commensurate vertical component associated with the net cable angle from horizontal.
If cables are to be anchored in multiple foundations, the design of safety terminal foundations and cable connections shall be based on a minimum equivalent horizontal static load of 15,000 lbf per cable and the commensurate vertical component associated with this force and each cable’s angle from horizontal.
All wire rope terminations shall be made with swaged type threaded terminals. Only 1 field-installed swaged terminal will be allowed per cable per run. All other swaged terminals shall be factory installed.
Intermediate line post spacing shall be such that the maximum reported NCHRP crash test dynamic deflection is no greater than 10 ft, but in no case shall the post spacing be greater than 16 ft. Post spacing may be adjusted, as allowed by the manufacturer, to avoid conflicts with utilities, drainage structures, underdrain outlets and other permanent obstructions.
Intermediate line posts shall be of a socket tube and post design where the socket is part of the line post foundation and line posts are inserted into the socket. Posts shall have a means of holding the wire ropes at the design height. The post and socket design shall include a means of excluding debris from entering the socket.
Foundations for intermediate line post sockets shall be cast-in-place concrete a minimum of 3 ft 6 in. deep and a minimum of 14 in. in diameter centered about the socket. Concrete foundations shall be reinforced as recommended by the manufacturer, but in no case shall the reinforcement be less than shown in the plans.
A minimum of 8 sq in. of retroreflective sheeting shall be applied on the side facing approaching traffic of each line post in cable height transition sections and to every 4th intermediate line post in full height cable sections. The color of the sheeting shall match the color of the nearest adjacent traffic pavement marking.
MATERIALS
627.03 Materials

Materials shall be in accordance with the following:
Concrete, Class A 702

Reinforcing Bars 703
Cables shall meet the manufacturer’s specifications. In addition, cables shall be 3/4 in. 3 x 7 zinc-coated wire rope in accordance with AASHTO M 30-02 (2006) Type 1, Class A and shall have a minimum breaking strength of 39,000 lbf. Wire rope shall be pre-stretched to exhibit a minimum modulus of elasticity of 11,805,000 psi.
Intermediate line posts shall meet the manufacturer’s specifications. In addition, posts shall be zinc-coated steel meeting the requirements of ASTM A 36 and AASHTO M 111M / M 111-04 after fabrication.
Swaged type threaded terminals, turnbuckles and anchor fittings shall meet the requirements of ANSI B1.13M and be zinc-coated in accordance with AASHTO M 232-06 after fabrication and shall develop a minimum breaking strength of 36,800 lbf. Turnbuckles may be either the open or closed body type and shall allow for a minimum of 6 in. of penetration from each end. Anchor fittings at the termination of each cable barrier run shall be of the same size and type used in connection to the turnbuckles.
Concrete for safety terminal and intermediate line post foundations shall be Class A.
Retroreflective sheeting shall be in accordance with ASTM D 4956 Type IV for adhesive sheeting.
A Type A certification in accordance with 916 shall be provided with each spool of wire rope cable prior to installation. The certification shall include the thickness of zinc coating, the minimum breaking strength, the modulus of elasticity and the force applied to pre-stretch the wire rope.
A Type C certification in accordance with 916 shall be provided for intermediate line posts, threaded terminals, turnbuckles, anchor fittings and retroreflective sheeting prior to installation.
CONSTRUCTION REQUIREMENTS
627.04 Construction

All site work, including grading and placing of fill shall be completed and approved by the Engineer prior to installation of the cable barrier system.
Installation of the cable barrier system shall be in accordance with the manufacturer’s recommendations and these specifications.
The top of cast-in-place concrete safety terminal foundations and intermediate line post foundations shall be finished no lower than flush with final grade and no higher than 1 in. above final grade. Intermediate line post foundations shall be installed such that line posts will be plumb when installed in the socket. Safety terminal foundation concrete shall be cured for a minimum of 168 h in accordance with 702.22 prior to tensioning of wire ropes.
A D2 delineator with post shall be placed in accordance with 804 in front of each safety terminal foundation.
Turnbuckles and other fittings shall be placed so as not to interfere with each other or with the intermediate line posts.
A manufacturer’s representative shall be present during tensioning of the system. Tensioning shall be done in accordance with the manufacturer’s specifications and using a tension chart provided by the manufacturer. The tension testing device shall be calibrated no more than 1 month prior to beginning tensioning and a copy of the calibration shall be provided to the Engineer. The temperature of the bottom wire rope shall be measured and recorded and used to determine the required tension values for the wire ropes from the manufacturer’s chart. A copy of the chart shall be provided to the Engineer prior to tensioning.
The Contractor shall maintain a tensioning log in a format acceptable to the Engineer to record, at a minimum, the following:
(a) The date tensioning is performed

(b) The ambient air temperature at the time of tensioning

(c) The temperature of the bottom wire rope at the time of tensioning

(d) The model and serial number of the tension testing device used

(e) The location of each safety terminal in the run being tensioned

(f) The location where tensioning is being performed

(g) A diagram showing the number assigned to each of the 4 wire ropes

(h) The wire rope number being tensioned

(i) The maximum stress applied to each wire rope

(j) The final stress applied to each wire rope
The tensioning log shall be signed by the person overseeing the tensioning and submitted to the Engineer upon completion of each day’s tensioning.
The tension in the cable barrier system shall be tested and retensioned as necessary no sooner than 15 days after initial tensioning. Retensioning shall be performed when the test indicates that tension is less than 90% of the manufacturer’s recommended tension for the given cable temperature.
A tensioning log for all runs retensioned shall be completed and signed by the person overseeing the tensioning and submitted to the Engineer upon completion of each day’s retensioning.
The Contractor shall provide for the manufacturer’s representative to be on-site to instruct Department personnel in the proper installation and repair procedures for the system.
The Contractor shall repair any portion of a cable barrier system, including wire ropes, intermediate line posts, safety terminals, retroreflective sheeting and hardware that is damaged as a direct result of traffic during the life of the contract. Damage shall be repaired within 7 days of notification by the Engineer. Responsibility for repairs will be in accordance with 107.18.
The Contractor may request final inspection and final acceptance of completed runs of cable barrier in accordance with 105.15(a).
The Contractor shall provide a spare parts package for the selected cable barrier system as defined below:
Qty Description
      Intermediate line posts and all associated hardware.
      Intermediate line post sockets and all associated hardware.

.

      Retroreflective sheeting.
      Manufacturer’s tools required to replace intermediate line posts.
      Tension testing device as produced by or recommended by the manufacturer.
      Tensioning device as produced by or recommended by the manufacturer.
      Complete set of manufacturer’s installation and repair manuals.
Prior to final acceptance of the contract, the spare parts package shall be delivered to a location within the District to be determined by the Engineer.
627.05 Method of Measurement

Cable barrier system will be measured by the linear foot for the type specified, complete in place. Measurement will be made between the centers of the 2 safety terminal foundations at the extreme ends of each run.
Safety terminals will be measured per each for the type specified, complete in place. One safety terminal will include all foundations and hardware necessary to anchor all 4 wire ropes at 1 end of a cable barrier run.
Safety terminal foundations, intermediate line posts, line post foundations, cable tensioning and retroreflective sheeting will not be measured separately for payment.
D2 delineators will be measured in accordance with 804.06.
Spare parts package will be measured per lump sum, complete and delivered to the Department.
627.06 Basis of Payment

Cable barrier system will be paid for at the contract unit price per linear foot for the type specified.
Safety terminals will be paid for at the contract unit price per each for the type specified.
D2 delineators will be paid in accordance with 804.07.
Spare parts package will be paid for at the contract unit price per lump sum.
Payment will be made under:
Pay Item Pay Unit Symbol
Cable Barrier System, Type TL- _____ LFT

(test level)
Cable Barrier System, Type TL- _____, Spare Parts LS

(test level)

Safety Terminal, Type TL-_____ EACH

(test level)
The cost of wire rope cables, intermediate line posts, line post foundations, cable tensioning, retroreflective sheeting and all equipment, parts and labor, including the cost of the manufacturer’s representative, necessary to furnish and install the cable barrier system shall be included in the cost of the pay item for cable barrier system.
The cost of safety terminal foundations, including reinforcing steel and all necessary cable anchor hardware, shall be included in the cost of the pay item for safety terminal.
The cost of obtaining any necessary additional geotechnical information and the cost of designing the safety terminal foundations shall be included in the cost of the pay item for safety terminal.
The cost of spare parts package shall include all costs necessary to deliver the spare parts to the designated location in the District.



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