Note: UK NA to BS EN 1991-2:2003 Table NA.1 contains a note which says α q1 = 1.0.įrom Clause NA.2.20 the transverse braking force = 50% of the longitudinal braking force = 194kN. The longitudinal force can be reversed similarly for the transverse force.įrom Clause 4.4.1 the longitudinal force = 0.6 x 1 x 2 x 300 + 0.1 x 1.0 x 9.0 x 3.0 x 10.0 = 387kN. Although the axle loads and UDL values have been shown as reduced by Ψ 1 it is usually more convenient to apply the 0.75 factor to the load effects rather than the loads.
The diagram above illustrates Group gr2 for a single 10m span deck with a two lane carriageway. The footway loading is reduced to 3kN/m 2 (0.6 x 5kN/m 2). Load Model 1 is combined with footway loading.
The Groups are referenced gr1a, gr1b, gr2, gr3, gr4, gr5 and gr6 and the load models used in each group are listed in Table N.A.3 of the UK NA (this overwrites Eurocode EN1991-2 Table 4.4a). Load Models 1 to 4 may be combined to form 'Groups' of traffic loads. GROUPS OF TRAFFIC LOADS (UK National Annex Table NA.3) The UK NA also applies this reduction to crowd loading on road bridges with loaded lengths greater than 30m. Unless specified otherwise the ULD load may be reduced for footway/cycleway bridges with loaded lengths greater than 10m. The "frequent" value of LM1 is used and positioned in adjacent lanes and within 5m of the front and rear axles of the SV or SOV vehicle.Ī uniformly distributed load of 5kN/m 2 used to represent crowd loading and may be applied to both road bridges and footway/cycleway bridges.
Load Model 1 is applied in combination with the SV or SOV vehicle loading. Only one SV or SOV vehicle is applied to the structure. Motorways & Trunk Roads = SV80, SV100, SV196Įach axle of the SV and SOV vehicles has to be multiplied by a Dynamic Amplification Factor (DAF) which varies from 1.2 to 1.07 for axles loads from 100kN to 225kN respectively. Recommend that the levels of SV loading are as follows: SV model vehicles (SV80, SV100 and SV196) are in accordance with the Special Types General Order (STGO) Regulations.The UK National Annex describes two groups of vehicles, SV and SOV vehicles. If the structure is to be designed for abnormal loads then vehicles from Load Model 3 will need to be considered. Effects under one 200kN wheel load should also be considered.ģ. This load model is more predominant on short span members up to about 7m and includes members such as deck slabs spanning between main beams. When the action is applied within 6m of an expansion joint then an additional dynamic amplification factor is applied. The UK use a 400kN axle load which includes a factor to allow for dynamic amplification effects.
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