TRAFFIC LOADS ON BRIDGES
Click on the Clause No. for the commentary.
Collision forces on vehicle restraint system
The UK National Annex cl. NA.2.30.2 revises the vertical load to 0.75 times LM1, but PD 6688-2:2011 Clause 3.13.1 suggests LM1 is αQ1Q1k and not (αQ1Q1k + αq1q1k) as defined in Cl.4.3.2.
[ Where αQ1Q1k = Tandem System & αq1q1k = UDL System ]
The British Standards Committee will be drafting amendments to PD6688-2 and UK NA to BS EN 1991-2 to clarify that both the Tandem System and UDL System should be applied.
Note: These vertical loads are applied on the deck in Notional Lane Nr. 1 together with the Accidental Axle Load and Collision Forces for high containment parapets (Class C and D in Table NA.6 of NA to BS EN 1991-2:2003).
Last Updated : 7/11/2014
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