Practices for High-Tension Cable Barriers (2016)

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40 Brifen Wire Rope Safety Fence (WRSF) Brifen was the first high-tension cable barrier system used in the U.S., installed in Oklahoma City in 2000. As reported in the survey, there are currently 40 states that use this WRSF system, comprising 95.2 percent of all the states that use high-tension cable systems (42). This system uses S- or Z-shaped posts and interweaves the cables between adjacent posts, resulting in a design that absorbs the energy of an impacting vehicle at each post. Each cable is placed on the opposite side of the posts from the cable below it, except for the top cable which is set into the slot at the top of each post. The lower cables are not attached to the posts, but rest on a small nylon “locating pegs” to position the cables at their proper heights. Cables are securely anchored to a single end terminal located at each end of the run. System Configurations It has been crash tested with both three- and four-cable con- figurations as shown below and is considered eligible by FHWA as either a NCHRP Report 350 TL-3 and TL-4 system. APPENDIX C Manufacturers Summary TL-3 – Three Cable FHWA Eligibility Letter – B-82C (May 26, 2005) TL-3 – Four Cable FHWA Eligibility Letter – B-82 (April 10, 2001) TL-4 – Four Cable* FHWA Eligibility Letter – B-82B (March 27, 2005) Cable Heights above ground Top Cable at 720 mm (28.3 in.) Middle Cable at 600 mm (23.6 in.) Bottom Cable at 460 mm (18.1 in.) • • • Cable Heights above ground Top Cable at 720 mm (28.3 in.) Two Middle Cables at 675 mm (26.6 in.) Bottom Cable at 510 mm (20 in.) • • • Cable Heights above ground Top Cable at 930 mm (36.6 in.) Two Middle Cables at 780 mm (30.7 in.) and 630 mm (24.8 in.) Bottom Cable 480 mm (18.9 in.) • • • *TL-4 WRSF, four-cable system is acceptable as a TL-3 barrier when placed no further than 1.2 m (4 feet) down a 1V:4H slope (for adjacent traffic impacts) and no closer than 3 m (10 feet) from the ditch bottom for opposite-side impacts (FHWA B-82-B).

41 System Components • Cable The Brifen WRSF is made up of 21-wire, 3/4 in. (19 mm) diameter galvanized wire rope and has a minimum break- ing strength of = 17.7 tonnes (39,000 pounds). To reduce stretching during impact, the cables are prestretched during manufacturing to exhibit a minimum modulus of elasticity of 11,805,090 pounds/in2 (8300 kg/mm2) after prestretch- ing. Cables are tensioned based on the ambient tempera- ture and this tension varies from 5700 pounds at 0°F to 2700 pounds at 100°F. It is important that cables be placed at the design height above the ground with a maximum deviation of ± 1 in. (25.4 mm). Generally, the cable heights are measured from the ground level beneath the line of WRSF, but when the horizontal distance from the WRSF is 2 feet (609.6 mm) or less from the edge of pavement, the cable heights are measured from the edge of the pavement. • Line Posts Posts have rounded edges on the traffic approach side and can be installed in a concrete socketed foundation, directly driven, set in driven socket foundations or surface mounted. Posts in concrete socketed foundations are the most commonly used option, as shown in this picture. The foun- dation has a 355.6 mm (14 in.) minimum diameter and its depth is determined by a geotechnical analysis. Post spacings are typically 3.2 m (10.5 ft), but the sys- tem has also been tested and is FHWA accepted with 2.4 m (7.87 ft) and 6.4 m (21 ft) spacings. Rope connection hard- ware (turnbuckles) are also tested and accepted for place- ment at a line post in the length of need. • End Anchor Terminal The Wire Rope Gating Terminal (WRGT) is a crash- worthy terminal (NCHRP Report 350, TL-3) and can be placed anywhere within the clear zone. It anchors all the ropes to one large reinforced concrete foundation offset 2 feet (609.6 mm) away from the line of barrier. There are two NCHRP Report 350 versions of this terminal: WRGT-FL and WRGT-RD. The WRGT-FL uses 4 special posts (Posts 1 thru 4) placed in socketed foundations. The Post 1 socket is placed at an angle towards the anchor. Each of the four posts has a weakening cut just above the ground line, which must be placed towards the anchor. Posts 2 and 3 do not have a slot at the top of the post. The WRGT-RD uses the standard line posts (with top slots) for posts 2 thru 4. This terminal met all the NCHRP Report 350 requirements except for the head-on impacts. It is typically placed near departing ends of bridges (or other shielded locations) and on downstream ends if out- side the clear zone for opposite-direction traffic. For all these terminals it is preferred that the concrete foundation be placed in excavations of natural undisturbed ground. The foundation sizes vary and depend on the soil type and condition, water table depth, temperature extremes, etc. Soil testing should be performed based on state policy or Brifen requirements.

42 BRIFEN Tension Cable Barrier System Specification (04/23/04)

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46 Gibraltar High-Tension Cable As shown from the survey, currently 35 states use this system, comprising 83.3 percent of all the states that use high-tension cable barrier (42). The system uses a distinctive steel hairpin and lockplate design that connects the cables to the C-channel posts. Posts are placed so the adjacent posts are on the opposite sides of the cables, in an alternating pattern. System Design It is available in both three- and four-cable configurations as shown below and is considered eligible by FHWA as a NCHRP Report 350 TL-3 or TL-4 system. System Components • Cable The cable is made up of 21 strands (3 × 7 configuration), ¾ in. (19 mm) diameter galvanized wire rope and has a minimum breaking strength of 18 tonnes (39,900 pounds). The cables are available prestretched and non-prestretched. • Line Posts The posts for the Gibraltar system alternate on the sides of the cable; therefore, post holes are augured 2 inches off the center line, on alternating sides with the “open” seam of the C-Section post, facing the center line. Line posts can be socketed or directly driven. TL-3 – Three Cable FHWA Eligibility Letter – B-137 (June 13. 2005) TL-4 – Three Cable FHWA Eligibility Letter – B-137A (September 9, 2005) TL-4 – Four Cable FHWA Eligibility Letter – B-137B (April 3, 2006) Cable Heights above ground Top Cable at 762 mm (30 in.) Middle Cable at 635 mm (25 in.) Bottom Cable at 508 mm (20 in.) • • • • • • • • • Cable Heights above ground Top Cable at 990 mm (39 in.) Middle Cables at 762 mm (30 in.) Bottom Cable at 508 mm (20 in.) Cable Heights above ground Top Cable at 990 mm (39 in.) Two Middle Cables at 762 mm (30 in.) and 635 mm (25 in.) Bottom Cable 508 mm (20 in.) Test Level 3 when placed on 6(H):1(V) or flatter Test Level 4 when placed on slopes of 6(H):1(V) or flatter; Rated TL-3 when placed on 4(H):1(V) slope Test Level 4 when placed on slopes of 6(H):1(V) or flatter; Rated TL-3 when placed on 4(H):1(V) slope

47 When solid rock is encountered: For a socketed post—continue digging hole, 15-in. deep into the rock or to the required depth shown on plans, whichever comes first. For driven post—drill a 4-in. diameter hole 18-in. deep into the rock or to the required depth shown on the plans, whichever comes first. For an anchor post, continue digging hole, 30-in. deep into rock or to the required plan depth shown on the plans, whichever comes first. Post spacing can be varied between 3 m (10 ft) and 9 m (30 ft) with this system. • End Anchor Terminal Gibraltar’s end anchor terminal section NCHRP Report 350 approved. It is crashworthy and can be installed in the clear zone. The end anchor consists of an in-ground anchor post, a cable release post and four terminal posts. The end terminal section is 27.5’ in length. End anchors should be installed in AASHTO standard soils and be well drained. If soils do not meet these criteria, then soil testing should be done by the DOT or contractor, as per the state’s specifications. Gibraltar High Tension Cable Barrier System Specification (02/12/2014) 1.0 Description. This work shall consist of all labor, equip- ment, and materials to install a 3-strand high-tension cable barrier system by furnishing and installing posts, cables, end anchors, and any special connections and fittings which may be required in the contract documents and per the manufacturer’s recommen- dations. The high-tension cable barrier system shall be approved by the U.S.DOT Federal Highway Administration for installation on slopes no steeper than 4(H):1(V) and also in accordance with the criteria contained in NCHRP Report 350, Test Level 4 when placed on slopes of 6(H):1(V) or flatter and Test Level 3 when placed on 4(H):1(V) or flatter. Acceptable systems and products shall include either a concrete socketed line post system, direct driven post system, or a driven socketed system design. All steel items are to be hot dipped galvanized. The high-tension cable barrier system shall be constructed as shown on the plans, with a maximum deflection of 9 ft 3 in. 2.0 Construction Requirements. Line posts shall be provided in accordance with the manufacturer’s shop drawings and shall be placed plumb. Spacing of the posts, sockets, and/or concrete footings shall be according to the manufacturer’s recommenda- tions based on deflection requirements. 3.0 Anchor Assemblies. An anchor assembly as specified in the manufacturer’s shop drawing shall be constructed at each end termination of the cable barrier run. The anchor assembly shall be approved by the U.S.DOT FHWA and also be in accor- dance with NCHRP Report 350, Test Level 3 criteria. Anchors shall be constructed in firm, stable, undisturbed soil to the mini- mum dimension shown on the shop drawings. Each end anchor shall be constructed according to the manufacturer’s recommen- dations for the site specific soil conditions. 4.0 Cable Tensioning. The cable height above finish grade shall be in accordance with the manufacturer’s shop drawings. The cable shall be tensioned immediately after initial installa- tion. Tension shall be rechecked and adjusted, if necessary, three to five days after initial tensioning. A tension log form shall be completed showing the time, date, location, cable and ambient temperatures, and final tension reading, signed by the person performing tensioning, and furnishing to the engineer upon completion of the work. 5.0 Delineators. High-tension cable barrier systems shall be delineated with retro-reflective sheeting. The sheeting shall provide a minimum of (10) square inches of area and shall be applied to the last five posts at each anchor section and to the line posts throughout the remainder of the installation at a maximum spacing of 60 feet. The delineation shall be attached near the top and side of the posts as recommended by the manufacturer. The sheeting shall be type III or IV, yellow or white, and shall be the same color as the adjacent pavement edge line markings. 6.0 Installation Training. Provide training by the manufac- turer prior to construction of the high-tension cable barrier for

48 the contractor, sub-contractor, and DOT personnel involved in the work. A supervisor, certified by the manufacturer, shall be on site during all phases of installation of the high-tension cable barrier. Additionally, after the system has been completed, train- ing shall be provided to any maintenance personnel, emergency response persons (police, fire, ambulance), as well as towing companies in the area. The training sessions shall be scheduled by the contractor in cooperation with the DOT on a date and location approved by the engineer. 7.0 Tensioning Tools and Repair Tools. One set of any spe- cial tools necessary for the tensioning of the cable system as recommended by the manufacturer or as necessary to repair and re-tension after damage to the system shall be provided to the engineer and retained by the DOT maintenance personnel at the completion of the contract. 8.0 Spare Parts. Spare parts will be provided consisting of enough parts to repair 10% of the total project LON. The parts will consist of posts, hairpins, and lock-plates, along with the above ground parts for one terminal section. The spare parts shall be delivered to the DOT maintenance office upon completion of the project. 9.0 Method of Measurement. High-tension cable barrier system will be measured by the linear foot and be the length of installation not including lengths of the high-tension cable barrier terminal sections. High-tension cable barrier terminal sections will be measured per each. 10.0 Basis of Payment. High-tension cable barrier, measured as prescribed above, shall be paid for at the contract bid prices per linear foot, which shall be full compensation for all materials, equipment, tools, staking, lay out, and labor necessary to com- plete installation of the high-tension cable barrier, including post foundations, delineation, other hardware, excavation and backfill- ing, and training necessary to complete the work. Cable barrier terminal sections, measured as prescribed above, shall be paid for at the contract bid price per each, which price shall be full compensation for all materials, equipment, tools, staking, lay out, and labor necessary to complete installation of the high-tension cable barrier terminal sections, including post foundations, delineation, anchors, reinforced steel, other hard- ware, and any excavation and backfilling, and training necessary to complete the work. Spare parts, measured as prescribed above, shall be paid for at the contract bid price per each lump sum, which shall be full compensation for all materials once delivered to the DOT main- tenance office per the direction of the engineer. Safence The Safence High-tension Cable System is manufactured and produced by Gregory Industries. As reported in the survey, 25 of 42 states (59.5 percent) that use HTCB use this system. System Configurations Safence has been crash tested with both three- and four-cable configurations as shown below and is considered eligible by FHWA as a NCHRP Report 350 TL-3 and TL-4 design, and as a MASH TL-3 system. The system configurations using the C-post with a vertical slot at the top of the post are shown below. The direct driven option is shown, but a socketed post design is also available with a 450 mm (17.7 in.) socket and 1230 mm (48 in.) long C-Posts. A MASH TL-3 system and a NCHRP 350 TL-3 system were tested with 3 cables (with a 4 cable option) when placed 4 feet from the hinge point on a 1V:4H slope. The posts can be driven directly into the ground or placed in sockets (Refer- ence FHWA eligibility letters B-88-F, December 23, 2008 and B-88-G, August 18, 2011). The MASH design had cable heights of 500 mm (19.7 in.), 785 mm (30.9 in.), and 975 mm (38.4 in.), with an option of adding a fourth cable midway between the two upper cables. The NCHRP Report 350 design used stiffened posts and a bottom cable mounted on the field side of the posts at 490 mm (19.3 in.). The upper cables were at the same heights as those in the aforementioned MASH test. System Components • Cable Pre-stretched (recommended) or standard cable is ¾ inch 3 × 7 steel cable manufactured in accordance with ASTM A741, AASHTO M30, Type 1, and Class A coating and ten- sioned per Safence tensioning chart. The cable shall have a minimum breaking strength of 17.7 tonnes (39,000 pounds). • Line Posts The C-posts are a cold-rolled design fabricated from ASTM A50 steel and galvanized per ASTM A123. Each post is slotted to hold the cables within the posts. Post spacing can be varied, on deflection requirements. Posts can be directly driven or set in socketed foundations. For socketed post foundations, a concrete footing with a mini- mum 12 in. diameter and a 24 in. depth, with a plastic or steel sleeve is used. The concrete foundation can either be precast or cast-in-place on site. Geotechnical reports may be needed to determine if additional depth is needed due to weak or saturated soil conditions.

49 • End Anchor Terminal The system uses non-releasable anchors, so the cables are likely to remain under tension after an impact. It is a NCHRP Report 350 TL-3 compliant design as a gating end terminal. The anchor block can be either prefabricated or cast on-site. Concrete shall be 3000 psi minimum and reinforced according to plan details. The End Terminals are installed in alignment with the barrier and each cable is attached to the anchor assembly. For all these terminals it is preferred that the concrete foundation for the end terminal be placed in excavations of natural undisturbed ground. The foundation sizes vary depending on the soil type and condition, water table depth, and temperature extremes. Soil testing should be per- formed based on state policy. SAFENCE High-tension Cable Barrier System Specification (08/10/2009): Description: The SAFENCE High-tension Cable Barrier (HTCB) is a NCHRP Report 350 approved TL-3 or TL-4 barrier that can be configured for use with three or four cables for median or shoulder applications, adopted new MASH standards for future testing procedures and product development. Safence (HTCB) contains errant vehicles through the help of lateral forces, which gradually redirect or capture the vehicle. Accomplished through the use of Safence (HTCB) end terminal and recom- mended post spacing to meet deflection requirements. Materials: Cable: Pre-stretched (recommended) or standard cable which shall be ¾ inch 3 × 7 steel cable manufactured in accordance with TL-3 – Four Cable FHWA Eligibility Letter – B-88A (January 28, 2004) TL-4 – Three Cable FHWA Eligibility Letter – B-88D (December 27, 2006) TL-4 – Four Cable FHWA Eligibility Letter – B-88E (July 31, 2007) Cable Heights above ground Top Cable at 720 mm (28.3 in.) Two Middle Cables at 640 mm (23.6 in.) and 560 mm (22 in.) Bottom Cable at 480 mm (18.9 in.) • • • Cable Heights above ground Top Cable at 720 mm (28.3 in.) Middle Cable at 640 mm (25.2 in.) Bottom Cable at 480 mm (18.9 in.) • • • Cable Heights above ground Top Cable at 720 mm (28.3 in.) Two Middle Cables at 640 mm (25.2 in.) and 560 mm (22 in.) Bottom Cable at 480 mm (18.9 in.) • • •

50 ASTM A741, AASHTO M30, Type 1, and Class A coating and tensioned per Safence tensioning chart. Post: C-post is of cold rolled design fabricated from ASTM A50 steel and galvanized per ASTM A123. Each post shall be slotted to hold cable within the post. Varying post spacing dependent upon working with requirements. C-post may be direct driven or socketed to meet states specifications. Post Hardware: A stiffening plate is added at ground level for resistance to bending with a steel hook added to the top to retain the cable within the post center slot. Plastic hardware is added within the post to keep cable heights consistent throughout the system whether it’s three or four cable with a stainless steel stiffening frame added between top and second cable for post strength. Cable Hardware: Machine swaged fittings recommended for added durability and safety. Shall be placed no more than 492 feet from end ter- minal and 1,000 feet or less thereafter. End Terminals: Safence Inc. NCHRP Report 350 compliant gating end ter- minal proven not to release ropes in crash testing approach impacts. Non-release capabilities retain ropes for secondary impacts. Length of terminal 39.36 feet. Concrete: Concrete shall be 3000 psi minimum and reinforced accord- ing to plan details. Tested with a minimum of 24″ concrete foundations. Installation: The installation of the Safence High-tension Cable Barrier System shall be according to the manufacturer’s installation manual and standard drawings and state specifications. Mea- surement will be by the linear foot between end terminals. End terminals will be measured per unit. Nu-Cable™ Nu-Cable high-tension cable barrier by Nucor Steel Marion, Inc., as reported in the survey, is currently being used by 61.9 per- cent (26 of 42) of states that use high-tension cable barrier. The system uses Rib-Bak®U-channel posts and standard (non- prestretched) or prestretched cables. Locking hook bolts are used to connect the cables to the posts. System Configurations It has been crash tested with both three- and four-cable con- figurations as shown below and is considered eligible by FHWA as both NCHRP Report 350 TL-3 and TL-4 systems. For the four- cable design, the lower two cables are attached using locking TL-3 – Three Cable FHWA Eligibility Letter – B-96 (August 30, 2002) TL-3 – Four Cable FHWA Eligibility Letter – B-193 (July 27, 2009) TL-4 – Four Cable FHWA Eligibility Letter – B-167 (January 24, 2008) FHWA Eligibility Letter – B-184 (December 9, 2008) Cable Heights above ground Top Cable at 750 mm (29.5 in.) Middle Cable at 650 mm (25.6 in.) Bottom Cable at 545 mm (21.4 in.) • • • Cable Heights above ground Top Cable at 1065 mm (42 in.) Two Middle Cables at 965 mm (38 in.) and 790 mm (31.1 in.) Bottom Cable at 485 mm (19.1 in.) • • • Cable Heights above ground Top Cable at 890 mm (35 in.) Two Middle Cables at 790 mm (31 in.) and 640 mm (25 in.) Bottom Cable at 380 mm (15 in.) • • •

51 hook bolts and the top two cables are supported by a top clip attached at the top of the U-post section. System Components • Cable The cable is made up of 21 stands (3 × 7 configuration) of ¾″ (19 mm) diameter galvanized wire rope with a mini- mum breaking strength of = 17.7 tonnes (39,000 pounds). The cables are available prestretched and non-prestretched. • Line Post The Nucor system uses Rib-Bak® U-channel posts and can be installed in a concrete socketed foundation, precast socketed foundation, and driven steel socket foundation, or they can be directly driven into the ground. Direct-Driven Line posts can only be used on the TL-3 systems. The post used is 1829 mm (72 in.) long with no soil plate and is driven to a depth of 991 mm (39 in.) into natural NCHRP Report 350 strong soil. If rock is encoun- tered, follow state’s procedure or drill a 4 in. diameter hole to accommodate a minimum of 15 in. of the line post. Concrete Socketed Foundations utilize a steel or plastic socket set into a 12 in. diameter × 30 in. deep (305 mm × 762 mm) concrete footing. The concrete footing is strengthened with a steel reinforcing ring and two steel dowels. Post spacing can be varied between 5 m (16 ft-5 in.) and 6 m (20 ft). • End Anchor Terminal There are two types of anchors that are available and have been accepted by FHWA and tested to NCHRP Report 350 TL-3 criteria: Nu-Ten and CRP (Cable Release Post) End Terminals. The Nu-Ten End Terminal is a crashworthy terminal and can be placed anywhere within the clear zone. It is used to anchor all the cables to one foundation. It utilizes a trigger post, which will disconnect all the cables upon impact. The CASS Cable Terminal (CCT) is the same terminal used with the CASS cable barrier system by Trinity High- way Industries. It consists of three Cable Release Posts and six S3 x 5.7 posts. For the TL-3 system the latter posts are 5 ft-3 in. long and for the TL-4 system their lengths vary between 5 ft-3 in. to 5 ft-11 in. The cables are connected to the posts 1 thru 6 with a special patented hook bolt that tapers each cable down to terminate at a cable release post. End anchors should be installed in AASHTO stan- dard soils and be well drained. If soil does not meet these criteria, then soil testing should be done by the DOT or contractor, as per state’s specifications, to determine the appropriate anchor size. Date acquired: 06/2015

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53 Trinity Highway Cable Safety System (CASS™) Based on the survey, currently 38 of the 42 states (90.5 per- cent) using HTCB use the CASS™. This system uses Steel Yielding Cable Posts (SYCP), that are designed with a propri- etary wave-shaped slot and weakening holes on the post at the ground line (for some systems). The cables are placed into these slots and are separated by plastic spacers at a specific design height giving the system the mechanism to restrain or redirect an errant vehicle. System Configurations The original CASS™ design used C-shaped posts with three cables and was tested to NCHRP Report 350 TL-3, but was later tested with an S4 7.7 lb. I-post that has weakening holes through each flange at ground level. System details are shown below: Additional designs using both three- and four-cable configura- tions and considered eligible by FHWA as a NCHRP Report 350 TL-3 or TL-4 system are shown below. All these systems use the I-Post design with weakening holes. These systems were also tested on a 1V:6H slope. TL-3 – Three Cable (C- & I-Post) FHWA Eligibility Letter – B-119 (May 13, 2003) – C-Post Design FHWA Eligibility Letter – B-141 (Nov 17, 2005) – I-Post Design with weakening holes. Cable Heights above ground Top Cable at 750 mm (29.5 in.) Middle Cable at 640 mm (25.2 in.) Bottom Cable at 530 mm (21 in.) • • •

54 Another design of the CASS™ system is shown below where the top two cables are positioned in the wave-shaped slot and the bottom two cables are supported by hook bolts on a S3 5.7 lb I-post. System Components • Cable The CASS™ uses a 19 mm (¾ in.) diameter, 3 × 7 strand pre-stretched (recommended) or standard cable with a mini- mum breaking strength of 17.5 tonnes (38,600 lb). Pre-Stretched Cable. The cable tension should be checked at least once a year. The tension value is based on either the ambient air temperature or the cable temperature, which can be taken using a thermometer for the air temperature or an infrared thermometer for the cable temperature. Standard Cable. The cable tension should be checked at least twice a year. The tension value is based on either the ambient air temperature or the cable temperature, which can be taken using a thermometer for the air temperature or an infrared thermometer for the cable temperature. • Line Posts The system line posts can be driven, placed in a driven sleeve, enclosed in a sleeve in a concrete footing (poured or pre-cast), or mounted to a concrete surface. For curves the post spacing may need to be reduced based on the radius and will be the same for both pre-stretched and standard cable. Post spacing are varies between 2 m (6.5 ft) and 9.7 m (32 ft). TL-4 – Three Cable FHWA Eligibility Letter – B-141 (Nov 17, 2005) Cable Heights above ground Top Cable at 968 mm (38 in.) Middle Cable at 750 mm (29.5 in.) Bottom Cable at 530 mm (21 in.) • • • • • • TL-4 – Three Cable* FHWA Eligibility Letter – B-141D (March 19, 2009) Cable Heights above ground Top Cable at 1060 mm (41.7 in.) Middle Cable at 745 mm (2 Bottom Cable at 445 mm (17.5 in.) 9.3 in.) TL-4 – Four Cable FHWA Eligibility Letter – B-157 (April 23, 2007) Cable Heights above ground Top Cable at 968 mm (38 in.) Two Middle Cables at 750 mm (29.5 in.) and 640 mm (25.2 in.) Bottom Cable 530 mm (21 in.) • • • *System variations: TL-4 – Three cable on a 1V:6H (shown above) TL-3 – Three cable system on a 1V:4H Slope – B-141C (Nov. 14, 2008) TL-4 – Four cable system with the addition of a 4th cable at 950 mm (37.4 in.) on a 1V:6H – B-141D TL • • • • -3 – Four cable system with the addition of a 4th cable at 950 mm (37.4 in.) on a 1V:4H – B-141D

55 TL-3 – Four Cable on 1V:4H* TL-4 – Four Cable on 1V:6H FHWA Eligibility Letter – B-141F (October 1, 2010) Cable Heights above ground Top Cable at 1070 mm (42.1 in.) Two Middle Cables at 960 mm (37.9 in.) and 755 mm (29.8 in.) Bottom Cable at 450 mm (17.8 in • • • .) *MASH tested as TL-3 system – B-232 (May 4, 2012) • End Anchor Terminal There are two methods to terminate the CASS system barrier: a NCHRP Report 350 Cable Terminal or a non- NCHRP Report 350 Cable Anchor. The CASS™ Cable Terminal (CCT) consists of Cable Release Posts (CRP) and six S3 x 5.7 posts. The cables are connected to the terminal line posts with a special patented hook bolt that tapers each cable down to terminate at a cable release post. The CASS™ Cable Anchor (CCA) anchors all the cables to one anchor block. This is not a crash tested system so it must be installed outside the clear zone or where it is effec- tively shielded from traffic. Additional options are available to connect the cables directly to w-beam or Thrie-beam guardrail or box beam or a rigid barrier wall system. The end terminals and line post foundation sizes vary, depending on the soil type and condition, water table depth, and temperature extremes. Soil testing should be performed using the state policy and specifications. For a standard line post, soil borings are required to be a minimum depth of 5 ft and for end terminals a minimum depth of 10 ft.

Abbreviations and acronyms used without definitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FAST Fixing America’s Surface Transportation Act (2015) FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) NASA National Aeronautics and Space Administration NASAO National Association of State Aviation Officials NCFRP National Cooperative Freight Research Program NCHRP National Cooperative Highway Research Program NHTSA National Highway Traffic Safety Administration NTSB National Transportation Safety Board PHMSA Pipeline and Hazardous Materials Safety Administration RITA Research and Innovative Technology Administration SAE Society of Automotive Engineers SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (2005) TCRP Transit Cooperative Research Program TDC Transit Development Corporation TEA-21 Transportation Equity Act for the 21st Century (1998) TRB Transportation Research Board TSA Transportation Security Administration U.S.DOT United States Department of Transportation

TRANSPORTATION RESEARCH BOARD 5 0 0 F ifth S tre e t, N W W a s h in g to n , D C 2 0 0 0 1 A D D R ESS SER VICE R EQ UESTED NO N-PRO FIT O RG . U.S. PO STAG E PA ID CO LUM BIA, M D PER M IT NO . 88 ISBN 978-0-309-27214-8 9 7 8 0 3 0 9 2 7 2 1 4 8 9 0 0 0 0