A comparison of laboratory tests and in situ pressure meter tests shows that the pressure meter can be used to infer the compressibility properties of shales in situ. The moduli values computed directly from the pressure meter tests, however, overestimate the '%'drained'%' modulus which must be used for design, and it is suggested that the appropriate deformation modulus for use in settlement calculations be taken as about one third of the moduli measured with the pressure meter. Laboratory and in situ tests indicate that both the moduli and strength can be correlated with initial water content for a given shale. These correlations can be used to estimate the moduli at locations on the basis of a water content profile in the absence of laboratory or pressure meter tests. Laboratory tests also indicate that the ratio of the deformation modulus to the compressive strength is a constant for a given shale; thus, the compressive strength can also be used as an index property to estimate the compressibility of a shale.
|Original language||English (US)|
|Number of pages||17|
|Journal||ASTM Special Technical Publication|
|State||Published - 1970|
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