Monitoring the second Heinenoord Tunnel and the Botlek Rail Tunnel

Two pilot projects for bored tunnelling in soft soil have been undertaken in the Netherlands under authority of the Centre for Underground Construction (COB). A description of the research related to the Second Heinenoord Tunnel and the Botlek Rail Tunnel will be given. The Second Heinenoord Tunnel has completed its boring works, while the boring of the Botlek Rail Tunnel has started in March/April 1999. Experience from the first project is put into use for the development of the latter. Both monitoring schemes have three logical phases: predictions, measuring and evaluation. An overview of all instrumentation and a selection of the results of the Second Heinenoord tunnel are given.