Figure 6.12: Deck with the fixed bearing not located at one end

(2)P For bridges carrying ballasted track with an expansion device adjacent to the moving end of the deck and continuous over the fixed bearing at the other end(class(5)(a) structures), the characteristic longitudinal action to be taken into account at the bearings is given by:

FTk= ± (400 + 5LT) in [kN] per track This force is limited to 1100 kN per track

(3) For any bridge where the track has expansion devices at both ends of the deck: Longitudinal actions due to traction and braking

(1)P For bridges carrying ballasted track, either continuous track or with an expansion device at one end, the characteristic traction/braking action (Q,ak or Qlbk) transferred by the deck to the bearings Fbk is the total action applied at the rail over the bridge multiplied by the coefficient given in Table 6.4.

Table 6.4: Coefficients for traction/braking actions resisted by the structure (class (5)(a) and (5)(b) structures)

Overall length of

Continuous track

Expansion device at one end

structure [m]

Single or double track

Single or double track

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