Probabilistic Time Estimation of Tunneling Projects: The Uri Headrace Tunnel

Probabilistic time estimation is an essential part of proper risk management in tunneling projects. In recent decades, several models have been developed for this purpose, one of which was developed by Isaksson and Stille (Rock Mech Rock Eng 38:373-398, 2005). In this paper, Isaksson and Stille's probabilistic time and cost estimation model was improved and then applied to estimate the total tunneling time of the headrace tunnel in the Uri hydropower project in India. The improvements allow the user to more accurately account for different types of geological features and disruptive events. The result of the estimation is a distribution of tunneling time. The outcome illustrates how a proper understanding of the geological setting of the project and its effect on construction performance can contribute to effective risk management.

Automated summary

In this study, the probabilistic time and cost estimation model was improved and applied to estimate the total tunneling time of the Uri hydropower project in India. The improvements allow for a more accurate consideration of geological features and disruptive events, resulting in a distribution of tunneling time. The study demonstrates the importance of understanding the geological setting and its impact on construction performance for effective risk management.