Application of Decision Aids for Tunneling (DAT) to a drill & blast tunnel

Probabilistic assessment of tunnel construction performance based on data

“…The unit costs and activity durations (advance rates) are commonly modeled using uniform, triangular or beta distribution (Min, 2003;van Dorp, 2005;Yang, 2007;Said et al, 2009). Triangular and uniform distributions are especially popular, because experts feel generally comfortable in assessing upper and lower bounds and the mean/mode of random variables.…”

Dynamic Bayesian Network for Probabilistic Modeling of Tunnel Excavation Processes

“…The variables to be used for describing the geotechnical conditions vary depending on the specifics of the tunneling project. The variables selected here follow the description in Min (2003). Within a segment i of the tunnel, the geotechnical conditions are described by the random variables zone Z i , rock class R i , height of the overburden O i , and ground class G i .…”

“…The construction method M i describes the excavation type and the related support pattern applied in the i th segment and is determined conditional on the ground class G i and tunnel geometry E i . The modeling of M i follows Min (2003), where the details of the construction methods are described.…”

“…A simplified version of the proposed DBN model, without consideration of extraordinary events, human factor H i and zone Z i , was previously applied to this tunnel in Špačková and Straub (2011), to validate the DBN model by comparing its results with those of the DAT model (Min, 2003). In Špačková and Straub (2011), the variable human factor H i is called quality Q i , its meaning and modeling is however the same.…”

“…The proposed DBN is applied to the case study originally presented in Min (2003) and Min et al (2003). The proposed DBN is here limited to estimating construction time, but adaptation of the model to predict construction cost is straightforward by simply replacing the variable time with variable cost.…”