Probabilistic estimation of ground condition and construction cost for mountain tunnels

• The Markov process and Bayesian updating are used to predict the ground condition.
• The cost variance is described by triangle distribution according to survey feedbacks.
• Ground condition and construction cost are estimated in a quantitative and probabilistic way.

An innovative methodology for the probabilistic estimation of ground condition and construction cost is proposed in this article, which is an integration of the geology prediction approach based on Markov process and the cost variance analysis based on work breakdown structure. The former one provides the probabilistic description of ground classification along tunnel alignment according to the geology information revealed from boring holes. The latter one provides the probabilistic description of expected cost for each interested operation according to the survey feedbacks among practitioners. Then an engineering application to Chuanshi Tunnel is well presented to demonstrate how the ground condition and the construction cost are estimated in a quantitative and probabilistic way. It facilitates both the owners and the contractors to be aware of the risk they should carry before construction, and it is meaningful for both tendering and bidding.