KIM – A method to estimate the relative density of calcareous sands

Franz Tschuchnigg, Macro Hofer

Research output: Chapter in Book/Report/Conference proceedingConference paperpeer-review


This paper describes the challenges that arise during quality control of deep vibro-compaction works onland reclamation projects. The aim of deep vibro-compaction is to densify the fill to a certain relative density ID, which
can be measured indirectly by performing Cone Penetration Tests (CPT). Due to the fact, that carbonate sands showsignificantly lower qc-values than silica sands under the same conditions well established empirical correlation methods
between the cone resistance qc and the relative density ID, which are mostly based on the results obtained from silicasands, cannot be used for carbonate sands. Therefore, the Karlsruhe Interpretation Method (KIM) is applied as correlation method within this paper. The KIM consists of numerical analyses of the spherical cavity expansion (SCE) problem and the empirical results of calibration chamber tests. This paper focuses on the FE model to solve the spherical cavity expansion problem using both, a hypoplastic and an elasto-plastic constitutive soil model. The paper investigates addition-ally the sensitivity of soil parameters on the results of a spherical cavity expansion analysis and comprises a model verification, where computed results are compared with closed form solutions. In addition, the hypoplastic soil parameter
calibration tool ExCalibre is discussed and finally, the automation of the whole KIM process is presented. The results of the paper clearly show, that the KIM, in combination with the proposed FE model, is a very powerful tool, which is able
to accommodate the intrinsic characteristics of calcareous sand.
Original languageGerman
Title of host publication6th International Conference on Geotechnical and Geophysical Site Characterization
Subtitle of host publicationToward synergy at site characterisation
Publication statusPublished - 1 Sep 2021

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