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Canada

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Fig. 2

Głacial lakes and marinę overlap (Prest 1961)

The one common soil formation found throughout Canada is glacial till. The standard penetra-tion test (S.P.T.) is used widely to evaluate the density State of the till, and also results in the recovery of samples suitable for classification purposes. Because of the variability of glacial till and frequent encounter with large stones or boulders, considerabie judgement is required in assessing the results of the S.P.T. Occasion-ally pockets of soft or loose till are encountered the S.P.T. has been useful in defining areas of "Iow blow" till.

Aside from the glacial till, the other soil de-posits in Canada have unique properties that have necessitated soil exploration methods that are tailored to particular requirements. Ex-amples of the types of practices used are re-ported frequently in dcscriptions of large pro-jects.

Review of Canadian Literaturę on Penetration Testing

The standard penetration test is commonly used in Canada and in generał follows the practice used in the U.S.A. The Boring and Sampling Committee of the Canadian Standards Associa-tion has prepared standard test procedures for the Standard Penetration Test and a Dynamie Cone Penetration Test (CSA 1960 and CSA 1962). Thcse are test procedures only and leave the interpretation of the test results to the designera Both methods are very similar to the procedures of the American Society for Testing and Materials. At present, there is no standard method for the use of the static cone test. When it is used, European, particularly Dutch, practice is followed.

For cohesioniess soils, the correlations of S.P.T. values with bearing capacity proposed by Meyerhof (1956 and 1959) are widely accepted.

In certain areas where the deposits of sand are extensive, local modifications of practice have been established. Tavenas et al (1970), Tavenas (1971) and Tavenas and Audy (1972) describe the application of penetration testing to a deposit of sand along the St. Charles River in the Ouebcc City region. Matich and Stermac (1971) illus-trate the usc of penetration tests in the investi-gations for the Burlington Bay Skyway structure which is founded on a sand bar at the mouth of Hamilton Harbour at the western end of Lakę Ontario.