It is in the calculations during the early stages of a construction project that cost estimates for tunnel construction goes wrong, such as City Tunnel and the tunnel under the Halland Ridge. Peter Lundman, PhD, has in a dissertation at Luleå University of Technology, among other things made a number of case studies of tunnel projects in Sweden
- Compared to earlier estimates with grand totals you nearly always find a more expensive total and not seldom it is huge, which means that there is much that can be improved, says Peter Lundman recent PhD research at Luleå University.
Peter Lundman currently working as acting technical director of major projects at the Transport Administration. He took his degree in Rock Mechanics at Luleå University in 1992 and has since been engaged in large construction sites, such as the Göta Tunnel. 2001, he was employed at the Swedish Railroad Autority and has among other things worked with the City Tunnel and the tunnel under the Halland Ridge.
A large part of the basis of Peter Lundman's thesis comes from case studies of some 20 underground projects in Sweden and interviews with project managers, consultants and contractors. In his research, he points to two unique conditions of the tunnels that make the early calculations uncertain, the first of which is about geology.
- The geological uncertainties are large, if we want to get better we should generally invest more in studies, alternatively the uncertanties can be reflected in the cost estimates, he says.
Safety aspects of tunnels at underground construction is another factor of uncertainty that is difficult to calculate in cost estimates according to Peter Lundman. They are both messy and expensive because of the enclosed space and is also influenced by both regulations and external partners. He calls for a knowledge bank with the analysis of completed projects that can be used in calculations of new projects.
- If we achive this way of working, we have an improvement platform that can provide both better estimates and thank´s to that limiting the number of problems, "he says.