Click on the Clause No. for the commentary.
|BS EN||CLAUSE No.||SUBJECT|
Traffic Loads on Bridges
|Cl. 184.108.40.206||Collision forces on vehicle restraint system|
|BS EN 1991-2 Traffic Loads on Bridges|
|Cl. NA.2.30||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).