Model CPTs in Chalk

TY - GEN

T1 - Model CPTs in Chalk

AU - Riccio, Thomas

AU - Ciantia, Matteo

AU - Previtali, Marco

AU - Brown, Michael J.

PY - 2024/6/7

Y1 - 2024/6/7

N2 - Cemented geomaterials exist in many parts of the world. Structure and bonding largely influence their strength, stiffness, permeability and other hydromechanical properties. Despite the CPT being the most widely used geotechnical engineering soil characterization tool, most existing correlations between penetration resistance and soil parameters apply only to uncemented granular deposits. Application of existing correlations to cemented geomaterials such as soft rocks can produce misleading interpretation making CPT application more challenging. In particular, CPT databases correlating tip resistance with yield stress of the intact material show a wide scatter prompting the need for a better understanding of the mechanics of cone penetration in soft bonded materials. In this work, 1g small-scale model CPTs are performed in a soft rock, whilst in-test X-ray techniques help to reveal mechanisms behind the penetration process. Thereafter, experimental results are compared to field scale results and those modelled using the Particle Finite Element method which is geared toward large deformation analyses. The combined interpretation of the experimental and numerical data is then used to discuss some of the unique attributes of CPT behaviour in soft rock.

AB - Cemented geomaterials exist in many parts of the world. Structure and bonding largely influence their strength, stiffness, permeability and other hydromechanical properties. Despite the CPT being the most widely used geotechnical engineering soil characterization tool, most existing correlations between penetration resistance and soil parameters apply only to uncemented granular deposits. Application of existing correlations to cemented geomaterials such as soft rocks can produce misleading interpretation making CPT application more challenging. In particular, CPT databases correlating tip resistance with yield stress of the intact material show a wide scatter prompting the need for a better understanding of the mechanics of cone penetration in soft bonded materials. In this work, 1g small-scale model CPTs are performed in a soft rock, whilst in-test X-ray techniques help to reveal mechanisms behind the penetration process. Thereafter, experimental results are compared to field scale results and those modelled using the Particle Finite Element method which is geared toward large deformation analyses. The combined interpretation of the experimental and numerical data is then used to discuss some of the unique attributes of CPT behaviour in soft rock.

U2 - 10.23967/isc.2024.299

DO - 10.23967/isc.2024.299

M3 - Conference contribution

T3 - Emerging technologies in site characterization for Offshore Wind Towers, 2024

BT - Proceedings of the 7th International Conference on Geotechnical and Geophysical Site Characterization ISC2024

PB - Scipedia

T2 - 7th International Conference on Geotechnical and Geophysical Site Characterization

Y2 - 18 June 2024 through 21 June 2024

ER -