My Geotechnical Quest – Netherlands / Czech Republic

04 februari 2015

JonathanHarrisI managed to arrive the day before to get my bearings in the Netherlands and managed to explore a small part of Utrecht where I will be staying for next three nights. The first day I have visited the Amersfoort office which was a lot bigger than i expected (700+ people here!)  I met with Peter Schouten and Jennifer Barker and discussed the projects that are undertaken with the Geotechnical team here in Amersfoort (quite substantially more impressive than the projects we undertake in the UK!).  Very interesting to see the differences from Geotechnical Engineering here and the Engineering Geology we mainly do in the UK.

JonathanHarris2In the afternoon Peter took me to visit Eindhoven Railway station where a new tunnel is being built alongside the existing tunnel.  The new tunnel is about 35m wide and is being constructed whilst the station remains fully operational, an impressive feat indeed!  I was most impressed by how new piles had been installed to support the existing beams all beneath the operational railway lines.

The next two days I went to visit some epic river defence systems; one in Bergambacht, one in Dordrecht and the last in Overdiepse Polder.  All three were very different and fairly impressive.  The first site comprises an upgrade of ~6km of dyke which runs through three villages.  A variety of improvement methods are being utilised to improve the dyke, all on the actual doorstep of people’s houses whilst occupied.  This includes the installation of 3m wide, 22m deep reinforced concrete sections adjacent to houses.

Hans Niemeijer and Hans Wismans  took me to visit two different flood defense systems; the first (at Dordrecht) we visited the dyke where they are hopeful that they can use formally contaminated sand which has been treated for use in the improvement (they find out tomorrow if they can keep it…fingers crossed).  I also witnessed a very impressive method of installing a material which helps settlement speed up by lowering water pressures (by using a large 360 tracked machine 15-20 m of material is pushed into the sand in about 5 seconds, cut off, then move to next location.  The machine is fitted with GPS to accurately mark out each install location).  In the afternoon we visited an equally impressive scheme (Overdiepse Polder) which is also massive.  The flood protection works involve lowering of dykes and building new farmsteads for 1 in 25 year flood events.  I was also shown a very bizarre (but very impressive) automated laser guided cow milking system (wasn’t expecting to see this!).

JonathanHarris3After a fantastic time in the Netherlands I flew to Prague to meet with Jan Novotny of ARCADIS Geotechnika. On the first day he showed me a current road construction between Bošov and Libkovice in the west of Czech Republic.  A very interesting project (for a geologist) as the bedrock changed throughout the length of the construction (which changed from basalt, mudstone to siltstone.) The only blight on the trip was a short sharp shower catching us when we were exposed!

After this he drove me to a near-by village for lunch in a brewery, the type of lunch i could get used to very easily! Once a beer was sampled (and unfortunately only the one) we drove to Březno where Jan has been studying a site where a complex landslip has been occurring.  A very interesting site with a whole range of slips, Jan even noted that in the 2 months since he was last there further collapse of the slope had occurred.

On my last day of the Quest and with Jan he drove me first to meet a colleague (Michal Hartman) in the ARCADIS Pardubice office.  There, we discussed a local motorway construction around Chrudim.  It was very interesting to see a range of geological processes which have in turn made a requirement for geotechnical solutions (for instance it was identified that a former river channel was present within the upper mudstone deposits which would form a localised weak spot for potential slope failure).  We visited three locations across the proposed route of the motorway, each showing a slightly different mechanism/problem and the suggested solutions.

I was sad to have oinly had 5 days of visiting sites but all good things must come to an end.  I had an extremely enjoyable time and learnt many things about large scale geotechnically influenced projects which are not (currently) present in the UK for ARCADIS.

Jonathan Harris, EC Harris