All seats were taken at Lankelma's 10th anniversary seminar. With technical content of the highest standard, international guest speakers included Tom Lunne, Norwegian Geotechnical Institute, and Mike Long, University College Dublin (abstracts below).
   
We also introduced the latest environmental cones for the delineation and quantification of potentially contaminated land, in conjunction with US sister company Lankelma ESCS (Expedited Site Characterisation Sevices).
     
The event was held at the Lankelma offices in Iden, East Sussex, giving delegates a chance to meet Lankelma staff.
   
“Just writing to thank you, your colleagues and co-speakers for an excellent day, on the basis of both its technical content and your hospitality”  - Jonathan Gammon, Divisional Director, Jacobs
   
The presentations are available to download from Lankelma’s filestore (see abstracts below). Email info@lankelma.com for details.
      
   
             
     
   
5 Presentations:  
    
   
 ■  Soil design parameters in soft clays from CPTU and laboratory tests
Tom Lunne, Norwegian Geotechnical Institute
   
For important projects where soft clays are involved the following approach has been found to give cost effective and reliable results:

• Choose one or more representative locations and obtain high quality samples to the depth  required for the foundation problem
   
• Carry out oedometer, triaxial and if relevant direct simple shear tests to determine required  soil design parameters
    
• Carry out high quality CPTU(s) beside the sampling bore hole(s)
     
• Develop correlations between the CPTU results and the soil parameters found from the  laboratory tests
     
• Carry out a network of CPTUs across the area as required
         
• Use the locally developed correlations to determine soil design parameters

Some practical examples of this approach will be shown, including results from Norway.
  
   
■  Use of the piezoball to attempt to characterise the strength of peat
Mike Long, University College Dublin
    
The assessment of the shear strength of peat has recently again become topical in Ireland and elsewhere due to the need to assess the risk of blanket bog stability during construction (mostly wind farm) activities and for road embankment stability determination. Given the nature of the terrain and the large and inaccessible areas involved in situ testing is highly desirable. 
   
In the past in-situ vane testing has been used. However the literature has cast doubts on the applicability of the vane and also the CPT for characterising the srength of peat.
 
In this talk attempts to characterise the strength of peat using the piezoball are described. It is by no means a finished piece of work and can be described as a work in progress. Work by Lankelma at several Irish blanket bog sites will be described. Parallel lab testing to provide correlations with the in situ data will also be outlined and preliminary simple correlations between ball resistance and undrained shear strength of peat introduced. It may also be possible to utilise the data to characterise the nature (degree of humification) of the material.
   
Problems such as instrument sensitivity, pore pressure response, difficulties in sampling and testing the material will also be described. 
  
 
■  Environmental site characterisation using CPT
Mike Fraser, Lankelma ESCS
    
Direct sensing methods developed in the US to provide advanced 3-D plume models, reduce the need for sampling and laboratory testing.
   
We will consider the technologies and equipment (MIP, LIF, FFD, UVOST etc) that will enable clients to:

  
■  Cone Penetration Testing in the Antarctic
Adrian McCallum, Scott Polar Research Institute
   
Innovative cone penetration testing was conducted on the Brunt Ice Shelf, near Halley Base, Antarctica over the Austral Summer 2009/2010. CPT soundings were obtained from both prepared and virgin sites, and preliminary interpretation was conducted in conjunction with gravimetric density profiles. 
   
Snow stratigraphy and snow-layer mechanical properties were examined, and layer horizons tracked spatially via ground penetrating radar. This presentation provides some preliminary insight into results obtained. The development of CPT in snow and ice may prove beneficial for the future development of polar infrastructure.

 
■   CPT in UK Geology
Brian Georgious, Gardline Geosciences
   
There are a number of myths surrounding the CPT including;

• The CPT cannot penetrate through hard ground / gravels;
  
• You cannot drill with the CPT 
  
• You cannot sample with the CPT. 

A variety of techniques will be illustrated that demonstrate that these myths are often spin and with little/ no substance.