Nosing Force Vertical Load

vertical load whose magnitude is equal to 5 kN/m .

Note : This load does not cover the effects of heavy site vehicles and other lorries commonly used for the placing of the backfill.

Section 6 Rail traffic actions and other actions specifically for railway bridges

6.1 Field of application

(1 )P This section applies to rail traffic on the standard-gauge and wide-gauge European mainline network.

(2)P This section is not applicable for actions due to

(a) narrow-gauge railways

(b) tramways and other light railways

(c) preservation railways

(d) rack and pinion railways

(e) funicular railways

Note 1: The loading and characteristic values of actions for these types of railways shall be given by the relevant authority.

Note 2: The load models defined in this section do not describe actual loads. They have been selected so that their effects, with dynamic increments taken into account separately, represent the effects of the service traffic. Where traffic outside the scope of the load models specified in this Part need to be considered, then alternative load models, with associated combination rules, should be defined or agreed by the relevant authority.

(3) Requirements are specified for the limits of deformation of structures carrying rail traffic to maintain the safety of operations and to ensure the comfort of passengers (see annex G).

(4) Two standard mixes of rail traffic are given as a basis for calculating the fatigue life of structures (see annex F).

(5) The self-weight of non-structural elements includes the weight of elements such as, for example, noise and safety barriers, signals, ducts and cables (except the forces due to the tension of the contact wire, catenaries supports, etc.).

6.2 Representation of actions 6.2.1 Nature of rail traffic loads

(1) General rules are given for the calculation of the associated dynamic effects, centrifugal forces, nosing forces, traction and braking forces and aerodynamic effects due to passing rail traffic (slipstream effect).

(2) Actions due to railway operations are given for:

- vertical loads: Load Model 71, Load Models SW, unloaded train

- dynamic effects

- centrifugal forces

- nosing forces

- traction and braking forces

- aerodynamic effects from passing trains (slipstream effects)

(3) Accidental actions are given for:

- effect of rail traffic derailment

- severance of overhead line equipment

- accidental action from road traffic

6.3 Vertical loads - characteristic values (static effects) 6.3.1 General

(1) The actions are defined by means of load models. Two models of railway loading are given; one to represent normal traffic on mainline railways (Load Model 71) and one to represent abnormal heavy loads (Load Models SW).

(2) Provision is made for varying the specified loading to allow for differences in the nature, volume and maximum weight of rail traffic on different railways, as well as different qualities of track.

(3)P Eccentricity of vertical loads (only Load Model 71)

The effect of lateral displacement of vertical loads shall be considered by taking the ratio of wheel loads on one axle as 1,25:1,00. The resulting eccentricity e is shown in Figure 6.1.

1,25

r 18

distance between wheel loads

Nosing Force Vertical Load

distance between wheel loads

Figure 6.1: Eccentricity of vertical loads

Figure 6.1: Eccentricity of vertical loads

6.3.2 Load Model 71

(1) The Load Model 71 represents the static effect of normal rail traffic. It represents the vertical load on the track.

(2)P The load arrangement and the characteristic values for vertical loads shall be taken as shown in Figure 6.2.

0vk=250kN250kN 250KN 250KN

, q^SOkN/m

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  • anselma
    What are nosing loads?
    3 months ago
  • Ayaan
    Is nosing force combined with centrifugal force for train loading?
    2 months ago

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