*2.4.3 Damage per vehicle-kilometer (Dn,km)*

In a further step the damage increments of every vehicle are related to length by means of unit-kilometer. The absolute value of the damage increment stays the same; however, the unit changes (see Eq. (38)).

$$\mathbf{D}\_{\mathbf{n},\mathbf{km}} = \mathbf{D}\_{\mathbf{n}} \times \mathbf{km} \tag{38}$$

Dn,km—damage increment per vehicle of one unit kilometer (unit\*km/vehicle); Dn—damage increment (n = 1, 2, 3, 4.1, 4.2, 5, 6, 7) (unit\*/vehicle); km—length (km).

\**Unit of the damage term: kN<sup>3</sup> (D1, D6 and D7), kN1.2 (D2), kW/mm<sup>2</sup> (D3), kN (D5) and D4.1 and D4.2 are unitless*

Due to Eq. (38), a length reference is established in the TDM and vehicle-kilometer are therefore included. This approach is similar to the conventional vehicle grosstonnes that turn into vehicle gross-ton-kilometer when length is considered.
