APPENDIX C

Survey of States Responses

As part of the literature review, the research team reviewed the survey questionnaires from both NCHRP Synthesis 493 and NCHRP Report 711. Overall, these surveys were aimed at collecting information from states on their use, selection, and placement criteria for high-tension cable barriers. Although this project will benefit from the information collected and synthesized in the previous studies, the objective of this project is more concerned with material properties, material testing, and coating requirements; thus, a survey that addressed material properties and states standard specifications/details/provisions was developed. The content of the survey that was distributed to the states included

• Twenty-five from NCHRP Synthesis 493. In some cases, it was necessary to edit the questions to add new information, or to improve comprehension;
• Five questions from NCHRP Report 711; and
• Eleven new questions that were designed to cover new content and were aimed at collecting material property, testing, and coating information.

A distribution list for the survey was assembled and included contacts from each of the 50 states. The survey was built using the online program SurveyMonkey, and the survey was opened for responses on October 21, 2022. Analysis of survey responses began on November 28, 2022; however, the survey link was not closed, to allow additional responses. The survey, as published on the SurveyMonkey site, can be found in Appendix B.

This analysis of the survey is a supplement to the State DOT Specifications and State DOT Practices chapters of the literature review, sections 2.3 and 2.4, respectively.

Contact Information and Agency of Respondents

The first set of questions in the state-of-practice HTCB survey offered respondents the opportunity to provide contact information and agency information. Nineteen respondents initiated the survey and completed Question 1. The 19 respondents represented 17 agencies; Michigan DOT and Minnesota DOT were represented by multiple respondents. One additional state, Connecticut, responded to the survey by directly emailing the research team. A map indicating the states that responded is shown as Figure C-1.

Types of Cable Barrier

Question 2 asked respondents what cable barrier types are currently being installed on the roadside or median by their agency. Seventeen of the respondents provided responses to this question. The answers provided can be seen in Figures C-2 and C-3 and in Table C-1. Of the

Table C-1. Tabulation of survey responses for Question 2.

17 states that responded, five were subsequently excluded from the survey analysis for the following reasons:

• Connecticut, New Jersey, and New Hampshire responded that they do not use cable barrier. The remainder of responses from these states were therefore omitted from the survey analysis.
• Vermont responded that their use of HTCB was limited to a pilot program that resulted in challenges with post replacement in inclement weather and that further use of HTCB has not been implemented. Since Vermont’s experience was limited to a pilot program, their responses were also excluded from the survey analysis.
• Alabama responded to Question 1 of the survey but provided no other responses to survey questions. Alabama’s responses were removed from the survey analysis; however, they are included in the review of State DOT Specifications and Special Provisions chapter of the literature review.

Types of HTCB

Question 3 asked respondents what HTCB-specific designs are approved/qualified for use by their agency. Thirteen participants responded to this question, and their responses are shown in Table C-2 and Figure C-4. Note that multiple responses were allowed to this question. Louisiana reported that they do not have an approved products list but that the cable barrier systems used in their state must be high-tension, 4-cable systems that meet MASH requirements and have an FHWA eligibility letter.

Table C-2. Tabulation of survey responses for Question 3.

Types of HTCB Terminals

Question 4 asked respondents what HTCB terminal designs are approved/qualified for use by their agency. Thirteen participants responded to this question, and their responses are shown in Table C-3 and Figure C-5. Multiple responses were allowed for this question. Again, Louisiana reported that they do not have an approved products list, but they require that systems used in their state must be 4-cable, high-tension MASH systems with an FHWA eligibility letter. Similarly, Minnesota requires that systems installed in their state have an eligibility letter from the FHWA and that the system meets or exceeds either MASH TL-3 or NCHRP Report 350 TL-3 requirements.

State Specifications for HTCB

Question 5 asked respondents if their agency has developed specifications for HTCB. Twelve participants responded to this question, and their responses are shown in Table C-4 and Figure C-6. Of the 12 respondents, two states indicated that their agency has developed specifications for each eligible system, four states have developed specifications but are not product specific, three states use manufacturer specifications, and three indicated that they have no specifications.

Table C-3. Tabulation of survey responses for Question 4.

Table C-4. Tabulation of survey responses for Question 5.

Questions 6 through 9 of the survey provided an opportunity for respondents to upload or provide links to their agency’s HTCB standard specifications and HTCB Standard Drawings. Six respondents provided access to standard specifications, and six respondents provided access to standard drawings.

Special Provisions for HTCB

Question 10 asked respondents if their agency has developed HTCB Special Provisions. Twelve participants responded to this question, and their responses are shown in Table C-5 and Figure C-7. Of the twelve respondents, five states have not developed special provisions for HTCB, five states have universal provisions that apply to any/all HTCB designs, one state develops special provisions on a project-by-project basis, and New York responded that they use standard anchor blocks that are designed based on the tension loads for each specific system.

Questions 11 and 12 of the survey provided an opportunity for respondents to upload or provide links to their agency’s HTCB special provisions. Five respondents provided access to their agency’s special provisions.

Material Specifications

Question 13 asked respondents if any material specifications for HTCB components are defined by their agency. Twelve participants responded to this question, and their responses are shown in Table C-6 and Figure C-8. Half of the respondents indicated that no material specifications were

Table C-5. Tabulation of survey responses for Question 10.

defined by their agency, and the other six agencies did have material specifications defined. All the respondents who answered “Yes” pointed the research team back to their standard specifications, details, or special provisions.

Table C-6. Tabulation of survey responses for Question 13.

Material Testing

Question 14 asked respondents if components used in HTCB are tested to confirm their material properties before installation. Twelve participants responded to this question, and their responses are shown in Table C-7 and Figure C-9. Note that multiple responses were allowed to this question. Of the 12 respondents, one agency performs testing on a random sample of components, eight agencies require the contractor/manufacturer to perform material testing and provide certificates of compliance, and four agencies do not require testing or certification.

Table C-7. Tabulation of survey responses for Question 14.

Material Testing – Specific Components

Question 15 asked respondents which HTCB system components are tested by their agency. Four participants responded to this question, and their responses are shown in Table C-8.

Material Testing - By Contractor/Supplier

Question 16 asked respondents which HTCB components are tested by the contractor or manufacturer. Six participants responded to this question, and their responses are shown in Table C-9.

Table C-8. Responses to Question 15.

Table C-9. Responses to Question 16.

Pull Testing of Cable and Fittings

Question 17 asked respondents if their agency requires pull testing of fully fitted splices to determine breaking strength. Eleven participants responded to this question, and their responses are shown in Table C-10 and Figure C-10. Of the 11 respondents, two states require pull testing to determine the breaking strength of the splice and nine states do not.

Table C-10. Tabulation of survey responses for Question 17.

Pre-Stretched Cable

Question 18 asked respondents if pre-stretching of the HTCB wire rope is required by their agency. Eleven participants responded to this question, and their responses are shown in Table C-11 and Figure C-11. Of the eleven respondents, seven states require pre-stretching of the cables and four states do not.

Table C-11. Tabulation of survey responses for Question 18.

Table C-12. Responses to Question 19.

Pre-Stretching Load Requirements

Question 19 asked respondents to specify their agency’s pre-stretching load requirement. Five participants responded to this question, and their responses are shown in Table C-12.

Median Versus Roadside Installations

Question 20 asked respondents where cable barrier systems are installed by their agency. Eleven participants responded to this question, and their responses are shown in Table C-13 and Figure C-12. Note that multiple responses were allowed to this question. All 11 respondents indicated that their agency uses HTCB in medians and seven of those also use HTCB in roadside applications.

Table C-13. Tabulation of survey responses for Question 20.

Number of Cables

Question 21 asked respondents if their agency specifies the minimum number of cables used. Eleven participants responded to this question, and their responses are shown in Table C-14 and Figure C-13. Of the 11 respondents, two agencies do not specify a minimum number of cables, two agencies specify a minimum of 3 cables, and seven agencies specify a minimum of 4 cables.

Table C-14. Tabulation of survey responses for Question 21.

Minimum Test Level

Question 22 asked respondents if their agency specifies the minimum system Test Level for HTCB systems installed in their state. Eleven participants responded to this question, and their responses are shown in Table C-15 and Figure C-14. Of the 11 respondents, two indicated that their agencies do not specify a minimum test level for HTCB, seven agencies specify a minimum of TL-3, and two agencies specify a minimum of TL-4 for HTCB.

Table C-17. Tabulation of survey responses for Question 24.

a specific HTCB system, and eight agencies use a site design that is independent of the system ultimately used.

Anchor Foundation Design

Question 25 asked respondents if HTCB anchor foundations are designed on a project-by-project basis according to the site-specific soil type/conditions. Eleven participants responded to this question, and their responses are shown in Table C-18 and Figure C-17. Of the 11 respondents, seven indicated that the designs are done by the HTCB manufacturer, and four indicated

Table C-18. Tabulation of survey responses for Question 25.

that their agency uses a standard design. Questions 26 and 27 of the survey provided an opportunity for respondents to upload or provide links of example anchor foundation designs. One respondent provided access to their design.

Anchor Foundation Placement and Spacing

Question 28 asked respondents how their agency determines the placement and spacing of HTCB anchor foundations. Ten participants responded to this question, and their responses are shown in Tables C-19 and C-20 and Figure C-18. Of the 10 respondents, four indicated that placement of anchor foundations is done by their agency based on state specifications, one indicated that the placement is determined by the HTCB manufacturer, and five of the respondents answered “other.” Their responses are provided in Table C-20.

Concrete Line Post Footing Design

Question 29 asked respondents if concrete line post footers are designated on a project-by-project basis based on the site-specific soil type/condition. Eleven participants responded to this question, and their responses are shown in Table C-21 and Figure C-19. Of the 11 respondents, two indicated that the line post footers are designed by the agency, five respondents indicated that the design is done by the HTCB manufacturer, three responded that no specific design is used,

Table C-19. Tabulation of survey responses for Question 28.

Table C-20. Responses for answer choice: “Other (please specify)” Question 28.

Table C-21. Tabulation of survey responses for Question 29.

and one indicated that socketed posts are not used. Questions 30 and 31 of the survey provided an opportunity for respondents to upload or provide links of an example concrete line post footing design. Two respondents provided access to an example concrete line post footing design.

Mow Strip Use

Question 32 asked respondents if mow strips are used at the respondent’s agency. Eleven participants responded to this question, and their responses are shown in Table C-22 and Figure C-20. Of the 11 respondents, three indicated that mow strips are used on all HTCB projects, one indicated that they are sometimes used on a project-by-project basis, and seven indicated that mow strips are not used by their agency.

Mow Strip Material

Question 33 asked respondents what material mow strips constructed of, if they are used. Four participants responded to this question, and their responses are shown in Table C-23.

Table C-22. Tabulation of survey responses for Question 32.

Table C-23. Responses to Question 33.

Design Modifications for Curves

Question 34 asked respondents if there is any design modification (post spacing) for horizontal or vertical curves. Eleven participants responded to this question, and their responses are shown in Table C-24 and Figure C-21. Of the 11 respondents, two indicated that the post spacing designs on horizontal and vertical curves are done by the state agency, three indicated that the designs are done by the HTCB manufacturer, and five indicated that their agency has no specific post spacing design for curves. NYDOT responded that they require 10-foot post spacing and do not allow installation of cable barriers on curves with a radius of less than 500 feet. Questions 35 through 38 of the survey provided an opportunity for respondents to upload or provide links to an example HTCB design for horizontal curves and vertical curves. None of the respondents provided access to an example HTCB design for horizontal curves and vertical curves.

HTCB to Other Barrier Transitions

Question 39 asked respondents how they address the interface/overlap of HTCB with a metal beam or concrete barrier. Ten participants responded to this question, and their responses are shown in Table C-25.

Design-Related HTCB Issues

Question 40 asked respondents if there are any design-related HTCB issues that they believe need to be addressed by additional research. Seven participants responded to this question, and their responses are shown in Table C-26. Questions 41 and 42 of the survey provided an

Table C-24. Tabulation of survey responses for Question 34.

Table C-25. Responses to Question 39.

Table C-26. Responses to Question 40.

opportunity for respondents to upload or provide links of typical design-related HTCB concerns. Utah Department of Transportation provided a photo of a typical design-related HTCB concern, shown in Figure C-22.

HTCB Challenges

Question 43 asked respondents if their agency experienced any challenges related to HTCB installation. Eleven participants responded to this question, and their responses are shown in Table C-27 and Figure C-23. Of the 11 respondents, six were not aware of any issues related to HTCB installations. Five participants followed up with a discussion of those challenges in the responses to Question 44. The responses are shown in Table C-28. Questions 45 and 46 of the survey provided an opportunity for respondents to upload or provide links of typical installation-related HTCB concerns. None of the respondents provided links or photos to their specific HTCB installation concerns.

Table C-27. Tabulation of survey responses for Question 43.

Table C-28. Responses to Question 44.

Table C-29. Tabulation of survey responses for Question 47.

Repair Material Requisition

Question 47 asked respondents how materials that are required for repair of the HTCB systems (e.g., wire rope, posts, turnbuckles, fittings, etc.) are acquired by their agency. Ten participants responded to this question, and their responses are shown in Table C-29 and Figure C-24. Of the 10 respondents, six indicated that repair material was acquired by the maintenance contractor, and three indicated that repair material was acquired directly from the manufacturer. Wisconsin selected “Other” and indicated that the state forces the purchase of hardware.

Quantity of Repair Materials

Question 48 asked respondents in the case that repair materials are provided by the installation contractor as part of the installation bid package, please describe how much repair materials are provided (e.g., a percentage of installation length, standard quantity for each piece, quantity as a function of system length, etc.). Since repair materials are not supplied by the installation contractor as part of the bid package (see Question 47), there were no responses provided for this question.

Table C-30. Tabulation of survey responses for Question 49.

Rusting and Oxidation

Question 49 asked respondents if their agency has noted concerns with rusting or oxidation of galvanized components of HTCB systems. Ten participants responded to this question, and their responses are shown in Table C-30 and Figure C-25. Of the 10 respondents, one indicated that rusting was an issue, and eight indicated that rusting was not an issue. New York reported that in isolated cases the socketed posts have corroded badly in the sockets.

Cable Tension Check Frequency

Question 50 asked respondents how frequently the cable tension is checked. Eleven participants responded to this question, and their responses are shown in Table C-31 and Figure C-26. Note that multiple selections could be made for this question. Maryland reported that the frequency at which repairs are made to their HTCB systems allows tension to be regularly checked.

Table C-31. Tabulation of survey responses for Question 50.

Anchor Foundation Movement Monitoring

Question 51 asked respondents if the in-service movement of anchor foundations is monitored. Eleven participants responded to this question, and their responses are shown in Table C-32 and Figure C-27. One of the respondents indicated that anchor movement was monitored only once after installation, two indicated that anchor movement was monitored after installation and then periodically thereafter, and eight indicated that anchor movement is never monitored.

Table C-32. Tabulation of survey responses for Question 51.

HTCB Failure Modes

Question 52 asked respondents to indicate if the following cable barrier failure modes have occurred to the HTCB installed by their agency. Ten participants responded to this question, and their responses are shown in Tables C-33 and C-34 and Figure C-28. Note that multiple selections were allowed for this question. The highest percentage of barrier failures were related to soil conditions at either end-anchors or post footers. However, Utah responded that changes within their standards have resolved most of the issues related to soil conditions around anchors.

Used Parts for Repairs

Question 53 asked respondents if their agency utilizes used parts in repairs and, if so, has it caused problems. Eleven participants responded to this question, and their responses are shown in Table C-35 and Figure C-29. Of the 11 respondents, one indicated that they have had problems

Table C-33. Tabulation of survey responses for Question 52.

Table C-34. Responses for answer choice: “Other (please specify)” Question 52.

Table C-35. Tabulation of survey responses for Question 53.

using used parts, two indicated that they have installed used parts with no issues, and eight respondents indicated that their agency has not installed used parts in repairs.

Table C-36. Tabulation of survey responses for Question 54.

HTCB In-Service Performance Evaluations

Question 54 asked respondents if their agency performed an in-service performance evaluation on any HTCB installations. Eleven participants responded to this question, and their responses are shown in Table C-36 and Figure C-30. Of the respondents, only two, Wisconsin and Florida, indicated that their agency had performed an ISPE on HTCB systems. Questions 55 and 56 of the survey provided an opportunity for respondents to upload or provide links to an ISPE report. One respondent provided access to an ISPE report.