Organisering och kontrakt i bergtunnelprojekt - kunskap i samverkan
This report describes and discusses decision processes, management principles, contracts, organizational processes and experiences from seven recently completed, ongoing and planned Swedish rock tunnel projects. There is also a review of the international and Swedish literature, including a number of recent studies. The aims of this investigation have been first to give an overview of contracting models used in Swedish tunnel projects, and also to analyse the implications of these practices for the ability to integrate key competences to successfully manage uncertainty. Furthermore, to examine how decisions about contracting methods and organization are made today, and ultimately to suggest viable decision processes, contracting methods and management principles for tunnel projects.
The case study projects included here are the Kattleberg tunnel north of Göteborg, the rock tunnel contract in the Malmö City tunnel, the Norrström tunnel and Station City in the Stockholm City Line, the two further Stockholm projects of the Norsborg subway depot and the Stigberget car park, the Stockholm Bypass project and the West Link project in Göteborg. These case studies cover different project stages and have been performed with a variety of methods, primarily by interviewing key participants. Findings include that the contract models used vary from strictly traditional remeasurement contracts to explicitly collaborative contracts. Although much of this organizational variety can be ascribed to varying rock conditions and other physical circumstances, it is also clear that organizational policies and individual preferences have been influential.
Underground construction is associated with uncertainty, and the parties need to jointly decide how to adapt the technical design to actual physical conditions as these become known. Also the management competence and routines should be continuously assessed to fit changing requirements during the project. Evidence of poor collaboration in traditional contracts is often brought up in both the literature and the case interviews. Nevertheless, in those case study projects that were finished or almost finished, collaboration between the parties was perceived by participants as good. When comparing projects, the level and intensity of collaboration appears to differ significantly between those with traditional contracts. Further, the explicitly collaborative projects, where risks are shared, are perceived as more collaborative than the most collaborative traditional projects.
A key issue in choosing the optimal contracting strategy for a rock tunnel project, including management competence and communication, is that this requires knowledge of geology, rock engineering principles and construction methods. The technical competence needs to be integrated with competence in law and project management. Such knowledge integration is also needed when developing of contracting models, where the special requirements of rock con-struction should be attended to. No significant changes have taken place during the last decade in the design of traditional remeasurement contracts in Sweden, despite that this is perceived as an area in need of development. This points at a weakness on an industry level in the ability to handle long term, systematic development of contracting models for infrastructure projects in general.
We conclude with six recommendations for the development of contracting and knowledge integration in rock construction and more generally in the infrastructure sector.