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Field Bending of Thrie Beam

State OH
Description Text Can you tell me if there is a maximum allowable *field* bending of thrie-beam out in the field? Correct or not, our specifications indicate that we have allowed w-beam to be curved to a maximum of a 70’ radius... Thoughts?
  • Guardrail
Other Keywords Thrie Beam
Date March 14, 2014


I have a couple of thoughts on field bending of thrie beam.

1.       We have previously bent thrie beam to a radius as small as 34’ here at the facility using a press and incremental bending as part of the bullnose project. We found that this was a pretty difficult process as it required many small incremental bends along the length of the beam to produce a consistent radius rather than hinging the beam. I believe that when we did it in the shop with a press, it required bending the rail every 9”-12” along a 12’-5” section.

2.       We would be concerned that this type of process may not be very controllable in a field situation and would lend to thrie beam that was plastically hinged or kinked in one or two locations rather than actually bent in a radius. Formation of a hinge in the rail could weaken the rail section. Thus, we believe that field bending could be done, but we would recommend that it be done gradually and that hinging of the rail be prevented.


Date March 17, 2014

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