Sustainable bridges –LCA for a composite and a concrete bridge - Economical Bridge Solutions based on Innovative Composite Dowels and Integrated Abutments - page 37

Figure 5: Life cycle of the bridge

However, some stages of the life cycle are excluded from the study: the finishing steps
of steel elements, the erection of the bridge and its use phase. These stages are shown in
Fig. 5 by a different colour pattern.
The finishing of steel elements consists in cutting and welding. A previous study has
shown that this step is negligible in an LCA of steel products because it is very small [4] and
has therefore not been included in this evaluation. Similarly, we assumed that the erection
phase was also fairly small and therefore was neglected. Finally the use phase of the bridges
is equivalent between the two solutions and is therefore not taken into account.

4. Life Cycle Inventory

4.1 General

The Life Cycle Inventory (LCI) collects the mass and energy balances for each process of the
life cycle. LCIs for unit processes are listed in Tab. 2.