Optimising life-cycle costs of tunnels 9 Apr 2015

In comparison to road alignments in open terrain, tunnels generate higher construction costs as well as increased operational costs. In practice, the initial costs represent the primary decision criterion in the planning phase of tunnels, whereas the subsequent or follow-up costs, respectively, are only estimated roughly.

The modular process model for the life-cycle cost analysis of tunnels

By applying the life-cycle perspective to all phases of an underground facility, the costs are optimized holistically. While this approach has gained wide acceptance for the assessment of long-term returns in the real estate sector, the transfer to engineering structures is not yet common. Consequently, the adaptation of the life-cycle concept to the characteristics of tunnels is stressed.

The life-cycle oriented perspective can either be started along with the planning of a new tunnel or it might be initiated when the refurbishment of a tunnel in operation becomes apparent. The starting point of the life-cycle cost calculation represents the net present value method, which is adapted for tunnels by establishing a modular process model. With the application of the modular process model, essential costs can be identified early.

Read the full text of the paper on the attached pdf