Material Requirements for High-Tension Cable Barriers: A Guide (2025)
Chapter: 8 Conclusions
CHAPTER 8
Conclusions
Longitudinal barriers on the United States NHS have long demonstrated effectiveness in reducing the severity of roadway departure crashes (FHWA 2020). High-tension cable barriers are an important category of roadside safety features that lead to decreased cross-median crashes when installed in medians and less severe roadside departure outcomes when installed on the roadside. The proprietary nature of the HTCB systems currently on the market leaves some ambiguity in proper site design, how jobs are solicited, correct installation and maintenance practices, and training.
The objective of this research was to develop a recommended HTCB Acceptance Plan to standardize various aspects of HTCB implementation, including project bidding, design specifications, installation, maintenance, and training. The research approach included a comprehensive literature review, a survey of state transportation agencies, interviews with HTCB manufacturers, and a peer review process.
Key outcomes of the research include the following:
- Development of a standalone NCHRP report as the recommended format for the HTCB Acceptance Plan, chosen for its flexibility and ease of implementation.
- Creation of a comprehensive Acceptance Plan covering topics such as terminology, manufacturer and system information, materials and testing, geotechnical analysis, site design considerations, installation and maintenance, and training recommendations.
- Proposed updates to AASHTO M 30 to align the specification with the higher breaking strength wire rope used in modern HTCB systems.
- Validation of the Acceptance Plan’s fairness, flexibility, and relevance through a peer review process involving subject matter experts from various stakeholder groups.
The recommended HTCB Acceptance Plan developed under this research represents a significant step toward standardizing and improving HTCB implementation across the United States. By addressing key aspects of HTCB systems, from materials and geotechnical analysis to installation, maintenance, and training, the Acceptance Plan provides a comprehensive resource for transportation agencies and other stakeholders.
The decision to publish the Acceptance Plan as an NCHRP report balances the need for authoritative guidance with the flexibility required to accommodate future innovations in HTCB technology. This format allows for easier adoption by transportation agencies while avoiding undue constraints on manufacturers.
The proposed updates to AASHTO M 30 further align industry standards with current practices, ensuring that specifications accurately reflect the high-strength wire rope used in
modern HTCB systems. This alignment will provide clearer guidance for both agencies and manufacturers.
Through its comprehensive approach and stakeholder engagement, this research has produced a valuable tool that can enhance the safety, efficiency, and consistency of HTCB implementations across the country. As the transportation landscape continues to evolve, the HTCB Acceptance Plan will serve as a foundation for ongoing improvements in roadside safety infrastructure.
