Ground sampling program at the CANLEX test sites

One of the primary objectives of the Canadian Liquefaction Experiment (CANL EX) project was to develop and evaluate undisturbed sampling techniques as part of the overall goal to focus and coordinate Canadian geotechnical expe rtise on the topic of soil liquefaction. Six sites were selected by the CAN LEX project in an attempt to characterize various deposits of loose sandy s oil. The sites consisted of a variety of soil deposits, including hydraulic ally placed sand deposits associated with the oil sands industry, natural s and deposits in the Fraser River Delta, and hydraulically placed sand depos its associated with the hard-rock mining industry. At each site, a target z one was selected and various methods of ground sampling were performed. The se included ground freezing and sampling, fixed piston tube sampling, Chris tensen double-tube core sampling, large-diameter sampling using the Laval s ampler, and sonic (rotary-vibratory) continuous coring. Ground freezing and sampling was performed at all six sites; the other methods were used at on ly some sites. Geophysical (gamma-gamma) logging was also performed in bore holes near the freeze pipe to independently measure in situ void ratios. Th is paper describes the techniques used in the ground-freezing and various s ampling programs and presents a summary of the results. Comparisons of void ratios measured for various types of samples and using geophysical logging are also made.