Quality in tunnelling

Quality in tunnelling means knowledge. Knowledge is necessary to answer correctly to the requirements of the Design that has been prepared for an underground work, planned for a solution in civil, environmental or industrial fields. Knowledge is necessary to learn and ‘‘copy’’ better what the previous Designers have done to find new solutions for tunnel construction. Knowledge is necessary to spread all over the technical world both the reasons of failures and the keys for success. Experience, good contracts, professionality, self responsibility and simple rules are the basis to reach the objectives fixed in the Design, that is to perform the underground work following the Quality procedures. The Working Group (WG) No. 16, appointed by the International Tunnelling Association (ITA) council during the annual meeting in Oslo on 1999, defined the main topics in Milan on 2001 and closed in Amsterdam on 2003 this document, which is aimed to give a comprehensive contribution for a good behaviour in the various stages of tunnelling. This is not a handbook, because each single phase is not analyzed in extreme detail, but it allows one to go through the interacting activities of the involved parties. It is not so easy to write about generics of Quality without the knowledge of what goes wrong: this was the main difficulty that the Working Group (WG) has encountered during its effort to give good suggestions. The members of the WG hope however that the culture of spreading of knowledge will reach the people involved in tunnelling, thus contributing to one of ITA aims, that is the contribution for a common language in the practice of tunnelling. It is necessary to promote a link between Committents or Contractors on one side and the national and international organizations, working groups and the Universities on the other, in each field of activity, aimed to a continuous and updated collection of references, because only this link will provide an enormous base of lessons learned directly from case histories. The difficulties due to the uncertainties of the geological characters can determine huge consequences and each effort should be done to define the position of the tunnel, the excavation and support methods, the environmental and safety effects, the time and cost of the alternative solutions. The purpose of this document is to encourage all the involved parties to develop and maintain good organization and communications and to put each stage of a work in a common layout.