Ten years of bored tunnels in The Netherlands: Part I, geotechnical issues

摘要

Ten years have passed since in 1997 for the first time construction of bored tunnels in theNetherlands soft soil was undertaken. Before that date essentially only immersed tunnels and cut-and-covertunnels were constructed in the Netherlands. The first two bored tunnels were Pilot Projects, the 2nd Heinenoordtunnel and the Botlek Rail tunnel. Since then a series of other bored tunnels has been constructed and someare still under construction today. At the beginning of this period, amongst others Bakker et al (1997), gave anoverview of the risks related to bored tunnels in soft ground and a plan for research related to the pilot projectswas developed. After that in 1999 the 2nd Heinenoord tunnel opened for the public, the "Jointed platform forBored tunnelling", in short GPB, was organized, to coordinate further research and monitoring of bored tunnels.This platform is supervised by the Center for Underground Construction. In this paper a summary is given ofsome of the most characteristic observations on these 10 years of underground construction in the Netherlands.In the first part of this paper the focus is on geotechnical interactions, and stability, whereas part two will focusmore on structural related issues.