Info

Traffic actions ^ unfavourable favourable

Other variable actions unfavourable favourable

Accidental actions

1,00

P = Persistent situtation T = Transient situation A = Accidental situation

1) Instead of using yG P >351 and the usual yQ for lateral earth pressure actions, the design ground properties may be introduced in accordance with ENV 1997 and a model factor Ysdis applied.

2) In this verification the characteristic values of all permanent actions from one source are multiplied by [1,35] if the total resulting action effect is unfavourable and by [1,0] if the total resulting action effect is favourable. See also the Note given in ENV 1991*1 clause 9.4.2(3a).

3) Unless otherwise specified the factors apply to the appropriate characteristic values defined in Part. 2.1.

4) In cases where the limit state is sensitive to variations in space of permanent actions, the upper and lower characteristic values of these actions should be taken in accordance with 4.2(3)P of ENV 1991-1.

5) Unless otherwise specified. For prestress by tendons this applies to the appropriate characteristic values defined in the relevant design Eurocode. Where prestress is induced by deformations imposed on the structure, the factors on G and the imposed deformations should be as defined in the relevant design Eurocodes.

6) Applicable only where settlements are to be assessed as the best estimate (see the design Eurocodes).

7) The components of traffic actions are introduced in combinations as one action by the relevant group of loads gr4.

(2) For verifications with regard to loss of static equilibrium and in some other cases where the variabilities of strengths of the structural material and of the ground have a relatively minor importance, the favourable and unfavourable parts of permanent actions should be considered as individual actions and, unless otherwise specified, the unfavourable and favourable parts should be associated with Yosup = I1ยป05] and Ycnf = [0,95] respectively. The other partial factors on actions are as in (1).

Note: See the relevant design Eurocodes.

G.2.4 4r factors for railway bridges

(1) Unless otherwise specified (e.g. in the relevant Part of ENV 1991 devoted to specific actions or in the design Eurocodes), ^-factors for railway bridges are taken as given in Table G.2. For traffic actions, they apply, where relevant, as well to the groups of loads defined in 6.8.2 as to the dominant component actions of the groups when they are considered separately.

Table G.2: t factors for railway bridges

Actions

to

Was this article helpful?

0 0

Post a comment