In situ shear wave velocity from multichannel analysis of surface waves (MASW) tests at eight Norwegian research sites

摘要

The Multichannel Analysis of Surface Waves (MASW) technique, usedto determine shear wave velocity (Vs) and hence small strain stiffness (Gmax), hasrecently generated considerable interest in the geophysics community. This is becauseof the ease of carrying out the test and analysis of the data. The objective of this workwas to assess the repeatability, accuracy and reliability of MASW surface wavemeasurements for use in engineering studies. Tests were carried out at 8 wellcharacterisedNorwegian clay, silt and sand research sites where Vs had already beenassessed using independent means. As well as being easy and quick to use MASWgave consistent and repeatable results and for the clay sites the MASW Vs profileswere similar to those obtained from other techniques. Reasonable results were alsoobtained for the silt and sand sites, with the best result being obtained for the finer silt.This work also confirms that MASW Vs clay profiles are comparable to thoseobtained by correlation with CPT. For these sites there also seems to be a goodcorrelation between normalised small strain shear modulus and in situ void ratio orwater content and the data fit well with published correlations for clays.