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UL differentiation between Restrained v/s Unrestrained

Posted by APalmost 6 years ago
UL differentiation between Restrained v/s Unrestrained

How does UL differntiate Restrained v/s Unrestrained? Is there a stiffness requirements?

steel protection,restrained vs unrestrained

1 Reply
Posted by Ernst Toussaintalmost 6 years ago

Hello AP and thank you for utilizing ASK Hilti! In structural engineering, the term "restraint" is used to denote how a beam is prevented from buckling. This may also mean buckling sideways as well. When we mean thermally restrained, this us usually under fire exposure as when the temperature rises (increases), the beam is not allowed to have any movement in the XYZ plane. This includes expansion and contraction as well as torsion. This is based on temperatures remaining below the 1040F under load. A thermally un-restrained beam is allowed to move in the event of fire exposure.