Recent years have seen an increased focus on the performance of roadside hardware. As the use of High-Tension Cable Barrier (HTCB) systems increased across the United States, the transportation industry determined a research need to summarize the state of practice for HTCB systems. NCHRP Synthesis Report 493: Practices for High-Tension Cable Barriers initiated this research by engaging state DOTs to identify and report on the current state of practice for HTCB systems. Information collected included state DOT specifications, special provisions, design standards, and installation and maintenance concerns. Additionally, information was obtained from HTCB systems manufacturers since HTCB systems eligible for use on U.S. public roads are proprietary. The conclusions from NCHRP Synthesis 493 summarized practices for any agency considering creating or modifying its own specification or special provision for HTCB. However, research was needed to develop draft specifications for the materials used in HTCB systems.

Under NCHRP Project 22-40, “Update to AASHTO M 180-18 and Associated Highway Guardrail Specifications,” Roadsafe, LLC was asked to conduct the project objective in two phases. The research findings from Phase I led to the publication of NCHRP Research Report 1020: Investigation of Material Requirements for Highway Guardrail Systems. In Phase II, Roadsafe LLC was asked to develop a guide with a proposed Recommended HTCB Acceptance Plan that catalogs standard materials and components used in HTCB systems. The development of this guide was based on the work plan that included: (1) a comprehensive review of AASHTO M 30-15 and its associated AASHTO and ASTM standards; (2) a state of practice survey and interviews to identify state DOTs using HCTB systems in medians or roadsides; (3) revisions to the Cable Barrier Acceptance Plan to facilitate efficient implementation methods for field inspection, manufacturer certification, independent lab certification, and sampling and testing by the owner; and (4) proposed draft language for consideration by AASHTO to incorporate in the next update of the AASHTO M 30-15. 

In addition to the guide published as NCHRP Research Report 1156, two deliverables are available on the TRB website at trb.org by searching for NCHRP Research Report 1156. The deliverables are as follows:

• Dissemination and Implementation Plan for Applying Research Findings and Products into Practice: Recommended HTCB Acceptance Plan
  
• Summary of Research and Findings: A Project Overview Presentation

STATUS: Published as NCHRP Research Report 1156: Material Requirements for Highway High-Tension Cable Barrier: A Guide.  This was a continuation project, for which the research was published as NCHRP Research Report 1020.