ABSTRACT
The bored tunnels cross a railway line twice. The first crossing is an embankment with two railway tracks at the northern boundary of Rotterdam. The drilling takes place in normally packed sands but above these sands loose packed sands are found. Therefore several field and laboratory tests were done to determine the soil parameters and the behaviour of these sands. An extensive soil investigation has been performed at the location of the crossing. Borings and CPT’s have been executed to determine the geological build-up of the soil layers. Laboratory testing has been carried out to examine the consistency of the soil, the material parameters. Ground movements due to tunneling can induce a loss of strength in the loose packed antropogene sand causing an amplification of movement or even failure in the form of slope slides. In situ testing of the density of the sand and laboratory testing were carried out to make sure the sand is highly sensitive to liquefaction.
