Effect of Spatial Correlation Length on the Interpretation of Normalized CPT Data Using a Kriging Approach

In geotechnical engineering analysis and design, the frequency and spacing of borehole information is of great interest, especially when field data are limited. This paper uses random field models to deal with uncertainty in soil properties owing to spatial variability, by analyzing in-situ cone penetration test CPT) data from a sandy site in northern Denmark. To provide a best estimate of properties between observation points in the random field, a Kriging interpolation approach has been applied. As expected, for small correlation lengths, the estimated field quantities at intermediate locations between data points are close to the mean value of the measured results, and a high uncertainty is associated with the estimate. A longer correlation length reduces the error and implies more variation in the estimated values between the data points. (C) 2015 American Society of Civil Engineers.