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"Slight" Modification to IL F-shape Temporary Concrete Barrier

Question
State	IL
Description Text	Recent discussions with industry indicates they feel that modifying the corners of the toe of the IL F-shape Temporary Concrete Barrier (TCB) from a 90-degree angle to a 45-degree angle (the exact dimension of this "chamfered" area was not defined) would make TCB less likely to be damaged when setting and relocating. We understand the importance of engaging the corners being part of the crash testing, energy absorption, and deflection performance. How would such a modification by chamfering the corners affect performance results of prior crash testing results and subsequent approval of this barrier as a Test Level 3 device meeting NCHRP 350 requirements?

Question

State

Description Text

Recent discussions with industry indicates they feel that modifying the corners of the toe of the IL F-shape Temporary Concrete Barrier (TCB) from a 90-degree angle to a 45-degree angle (the exact dimension of this "chamfered" area was not defined) would make TCB less likely to be damaged when setting and relocating. We understand the importance of engaging the corners being part of the crash testing, energy absorption, and deflection performance. How would such a modification by chamfering the corners affect performance results of prior crash testing results and subsequent approval of this barrier as a Test Level 3 device meeting NCHRP 350 requirements?

System Performance Evaluation

System Types
Portable Barriers

Applications

System Features

Date November 25, 2013
Previous Views (142) Favorites (0)

Response
Response (active)	We have observed several other states providing similar types of chamfers on their barrier edges to limit damage to the sections during moving and placement. Typically, we have seen and approved the use of 3/4" chamfers on the barrier edges and believe that the affect of that size of chamfer on barrier safety performance is minimal. Similarly, we would not expect a 1" chamfer to affect safety performance and would consider it acceptable. However, larger chamfers (2" or greater) may begin to cause some concern.

Response

Response
(active)

We have observed several other states providing similar types of chamfers on their barrier edges to limit damage to the sections during moving and placement.

Typically, we have seen and approved the use of 3/4" chamfers on the barrier edges and believe that the affect of that size of chamfer on barrier safety performance is minimal.

Similarly, we would not expect a 1" chamfer to affect safety performance and would consider it acceptable. However, larger chamfers (2" or greater) may begin to cause some concern.

Date November 25, 2013
Previous Views (142) Favorites (0)