Abstract
Recent UK and other practice in the use of empirical ground classification systems for the selection of tunnel support is examined to identify new developments and note particular problem areas. The concept and nature of the systems are discussed in the first section. Recent literature is then examined and discussed, followed by a review of UK case histories of tunnelling where ground classification schemes were used. Final sections draw together the most important conclusions to be gleaned from the evidence and some guidance is provided on the practical application of the systems. Recommendations are also made on the possible direction of future research. (A)