Assessment of TBM and D&B Based on Excavation Time and Costs

By means of the latest NTNU prediction models for time and costs, the productivity and efficiency of the TBM and D&B options have been investigated. The weekly advance rate and unit excavation costs as a function of rock conditions and tunnel geometry are presented. As a result, the efficient and cost effective method for a tunnel is subject to mainly rock conditions, tunnel cross section area, length and tunnel application. Under Norwegian costing, for hard rock (poor boreability), the D&B method is cost effective whereas in small and long tunnels with good boreability the cost associated to the TBM is lower. Generally, the TBM has higher advance rate, and the rock conditions has a substantial impact on the TBM performance and costs.

کلیدواژه ها:

TBM tunnelling ، drill and blast tunnelling ، tunnel excavation time and costs