Determination of efficient sampling locations in geotechnical site characterization using information entropy and Bayesian compressive sampling

Abstract

Site characterization is indispensable in geotechnical engineering practice, and measurements on soil properties are performed through in situ tests, laboratory tests or other methods. However, due to time or budget limit, technical or access constraints, etc., the measurements are usually taken at a limited number of locations. This leads to a question of how to select the efficient locations for measurements or sampling such that as much information as possible on the spatial variability of soil properties can be obtained from a given number of measurements. In addition, geotechnical site characterization is a multi-stage process, and additional measurements might be required at a later stage of site characterization. In such a case, how the additional sampling locations can be selected efficiently such that the pre-existing measurements obtained from the preliminary stages of site characterization can be best used and how can as much information as possible on soil properties be further obtained are problems engineers face. This paper aims to address these two problems using information entropy and Bayesian compressive sampling. Real cone penetration test data along both vertical and horizontal directions are used to illustrate and validate the proposed methods. Results show that the proposed methods are very effective and robust in selecting efficient sampling locations for geotechnical site characterization.

Adaptive Fusion Sampling Strategy Combining Geotechnical and Geophysical Data for Evaluating Two-Dimensional Soil Liquefaction Potential and Reconsolidation Settlement

“…represents the sum of the variances of FIII ((q c1N ) cs ) interpreted along the depth at a given location j. The optimal location for fusion sampling is the FIII location with the largest sum of variances (with the largest uncertainty), which is consistent with engineering judgments [42]. As MS-BCS proceeds, the uncertainty in the process typically decreases, defining reliability level (COV M+N ) to interpret FIII .…”

Influence of Schistosity Orientation on Failure Mode and Indirect Tensile Strength of Mica Schist

“…Often, geotechnical coring for foundation systems is only conducted in a vertical direction. The low budgets for geotechnical site characterization [37] often preclude in-depth studies of intact rock properties. In such cases, the geotechnical design must rely on properties obtained from nonorientated core samples.…”

Selection of standard penetration test number for geotechnical investigation of a vertical cross section considering spatial variability and correlation in soil properties

“…along a horizontal direction (e.g., direction) where SPTs are performed. Note that SPT is 1 x generally performed with a depth interval, =1.0m-5.0m, and an equal spacing along the v d horizontal direction is usually adopted in engineering practice (e.g., Mayne et al 2002;Zhao and Wang 2019;Guan et al 2020). In Step 4, the extracted measurement data for each borehole number with different depth intervals (e.g., =1m, 1.5m, 2.5m, 3m, 5m) are used to v d interpolate cross-section of SPT data, which has the same dimension with the given crosssection of SPT data using an interpolation method (e.g., 2D Bayesian compressive sampling (BCS)).…”