摘要: |
The objective of this study was to develop a suitable replacement for the downstream turndown guardrail anchor system. The turndown guardrail anchor system does not meet mandated test requirements under MASH for upstream anchor application terminals; however, it does meet downstream requirements for previous crash testing standards. Due to its low cost, TxDOT has used this anchor system with 27-inch guardrail in downstream applications when it is outside of the clear zone of opposing traffic. With the new federally mandated increase in guardrail height, TxDOT is considering increasing its standard guardrail height to 31 inches. This increase in height increases the risk of a small sedan wedging under the guardrail and snagging on the turndown anchor system. The current turndown anchor design does not include a releasable connection detail for reverse direction impacts. For this reason, TxDOT has decided to develop a new downstream anchor system rather than test the 31-inch configuration of the turndown anchor system. This anchor system utilized standard parts found in the AASHTO-ARTBA-AGC Guide to Standardized Highway Barrier Hardware when possible. This terminal is nonproprietary to allow for competitive bidding to reduce costs. As this system will be developed for the sole purpose of anchoring the downstream end of guardrail system, the testing matrix will include the optional crash test (3-37) found in MASH for testing terminals in a reverse direction impact condition. |