EVALUATION OF GEOLOGICAL SURVEYS FOR MOUNTAIN TUNNEL USING ANALYSIS METHOD OF GEOTECHNICAL RISKS

Abstract

  This study evaluates the effect of geotechnical risks on cost variations in construction projects of mountain tunnels by post-evaluation, investigating the value of preliminary geological surveys to reduce the geotechnical risk. Specifically, a difference between the cost estimated by geostatistics and the actual cost used as an index of cost variation risks, a decrease of additional costs by an improvement of the difference is considered to be the quantitative value of geological surveys. As the result, it is able to evaluate a change of the difference with proceedings of surveys, and to show the index on the decision for efficiently carrying out limited preliminary geological survey.