TBM Station Transits
Summary
Providing parallel access into tunnels during its construction is a key factor for optimising programme. However a tunnel is a linear work site where sharing of the space between several contractors brings with it interfacing issues and associated risks that may in turn negate the benefit gained from parallel working.
This paper considers the construction of station platform tunnels ahead of TBM constructed tunnels to optimise the project construction programme. As a result the TBMs are required to transit through the stations.
TBM transits can be summarised into three distinct phases; reception, transit and relaunch. The paper discusses the requirements and considerations for each phase of the transit. It looks at the designs of the reception and launch chambers. It discusses TBM transit alignments and clash detection. The paper draws examples from the systems used for transiting through bored tunnels stations with some comparison undertaken with a box station.