cos (27โโ ), and cos ยก2k~โ I is taken as positive. V2keres0 \2keresJ

cos |2.rr 1 is taken as positive; and V2kres0

f' and f" are as defined in ENV 1991-3:1995, annex E; f' is calculated from kres (see H.2.2);

F** is a single force representing the equally spaced group of axles rag of a train (kN);

EUDLhag is the equivalent uniformly distributed load representing the heaviest group of axles of a train (kN);

EUDLLM71 is the equivalent uniformly distributed load representing load model 71 (kN). F is as defined in ENV 1991-3:1995, 6.4.3.2.

H.3.2 Additional check for load effects of heaviest group of axles of a train at kmax:

where f' and f" are as defined in ENV 1991-3:1995, annex E, and f' is calculated from kmax; F is as defined in ENV 1991-3:1995, 6.4.3.2.

H.4 General conditions

H.4.1 All conditions shall be conformed to in applying the simplified method, otherwise a special study should be undertaken.

At least train types 3 and 4 (see annex F), together with any other planned or foreseeable trains for which v > 220 km/h, should be considered.

The value of cos (p/2kres) should be taken as positive.

When calculating Frag or F^ag for a group of axle loads, only the axles within a group that can be placed on the bridge span should be taken into account.

NOTE ** If the group of axles comprises more than one axle, the equivalent single force representing the group of axles should be obtained by summation of the individual axle loads. If the conditions do not apply, the summation of the individual axles may be represented by the expressions in H.4.3 and H.4.4. The expressions are derived from a sinusoidal influence line of length L for forced vibrations and of length kL for free vibrations. The centre of gravity of the group of axles is assumed to coincide with the position of the maximum value of the appropriate influence line.

H.4.2 For symmetric and equal groups of axles: Crf2 x repeated axle load (two axles); Crf4 x repeated axle load (four axles); where

Crf2 and Crf4 are defined in H.4.3 and H.4.4 respectively. H.4.3 For axle loads comprising a single two axle bogie (with equal axle loads): Crf2 = 2cos b where p when considering free vibrations (repetitive axle loads);

p when considering forced vibrations (heaviest axle loads);

S1 is the half distance between axles.

H.4.4 For axle loads comprising two sets of two axle bogies (with equal and symmetrical axle loads):

g = kL S and b = kL when considering free vibrations (repetitive axle loads);

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