Site characterization based on adequate investigation and accounting for site variability is a prime requirement for different design codes in Geotechnical engineering. Site variability is commonly evaluated through the determination of the first and the second-moment statistics (Statistical Variable Parameters), then evaluating the spatial variability of the considered parameter or variable using a relevant geostatistical method or tool. In this paper, the considered parameter or variable is the Standard Penetration Test blow count and the applied geostatistical tool is called variogram. The Standard Penetration Test (SPT), despite the inherent variability and measurement error, is still one of the most commonly used in-situ tests, and sometimes is the only available test, for site characterization. Even more, some geotechnical design methods are based directly on SPT measurement, or indirectly on a relevant correlation. Variogram is a simple geostatistical tool that is normally used to investigate the distance or the domain over which parameters are auto-correlated and the value of unmeasured point could be predicted. The purpose of the analyses carried out in this paper is to study the suitability of the variogram to investigate the spatial variability and the auto-correlated domain of a site using SPT blow counts.
Subjects: site characterization, spatial variability, geospatial method, variogram
Author: Salwa Yassin, MICE, CENG, Ph.D.
Publisher: DFI, EFFC