Numerical Analysis of FFP Impact on Saturated Sands
Publication: Geo-Congress 2023
ABSTRACT
Free-fall penetrometer (FFP) testing is a simple and rapid way of seabed sediment characterization that is more cost-effective than conventional geotechnical testing. Due to the dynamic nature of soil penetration during free-fall impact, loading rate effects are also recorded. As a result, a process to filter out the dynamic effects is required. However, removing the effects of high-strain rate (HSR) loading is challenging and favors the use of empirical correlations over analytical solutions. This study aims to numerically analyze FFP calibration chamber testing of saturated loose sands using the material point method (MPM). A fully coupled hydro-mechanical formulation is used to simulate the transient drainage that occurs during FFP deployment. Numerical models using material properties based on the bench-scale testing performed in quasi-static conditions result in lower tip resistance than the one obtained from the calibration chamber test. Parametric analyses show that dilation plays an essential role in the response of saturated sand and that HSR effects must be considered to capture sand behavior in such conditions. Finally, a comparative analysis of numerical CPT (quasi-static) and FFP test results is conducted to examine the effectiveness of logarithmic strain-rate correction procedure that is commonly used in practice.
Get full access to this article
View all available purchase options and get full access to this chapter.
REFERENCES
Al-Kafaji, I. K. J. (2013). Formulation of a Dynamic Material Point Method (MPM) for Geomechanical Problems. Ph.D. thesis, University of Stuttgart, Stuttgart.
Albatal, A. (2018). Advancement of using portable free fall penetrometers for geotechnical site characterization of energetic sandy nearshore areas. Ph.D. thesis, Virginia Polytechnic Institute and State University, Blacksburg.
Albatal, A., Stark, N., and Castellanos, B. (2019). “Estimating in situ relative density and friction angle of nearshore sand from portable free fall penetrometer tests.” Canadian Geotechnical Journal.
Aubeny, C. P., and Shi, H. (2006). “Interpretation of Impact Penetration Measurements in Soft Clays.” Journal of Geotechnical and Geoenvironmental Engineering, 132(6), 770–777.
Bardenhagen, S. G., Guilkey, J. E., Roessig, K. M., Brackbill, J. U., Witzel, W. M., and Foster, J. C. (2001). “An improved contact algorithm for the material point method and application to stress propagation in granular material.” CMES -Computer Modeling in Engineering and Sciences, 2(4), 509–522.
Bolton, M. D. (1986). The strength and dilatancy of sands. Geotechnique 36, 65–78.
Carrier, W. D. (2003). “Goodbye, hazen; hello, kozeny-carman.” Journal of Geotechnical and Geoenvironmental Engineering, 129(11), 1054–1056. https://doi.org/10.1061/(ASCE)1090-0241(2003)129:11(1054).
Dayal, U., and Allen, J. H. (1973). “Instrumented impact cone penetrometer.” Canadian Geotechnical J., 10(3), 397–409.
Durgunoglu, H., and Mitchell, J. K. (1973). Static Penetration Resistance of Soils. Technical Report. Space Sciences Laboratory. Berkeley, CA.
Jaky, J. (1944). “The coefficient of earth pressure at rest. In Hungarian “A nyugalmi nyomas tenyezoje.” J. Soc. Hung. Eng. Arch. (Magyar Mernok es Epitesz-Egylet Kozlonye), 355–358.
Moavenian, M. H., Nazem, M., Carter, J. P., and Randolph, M. F. (2016). “Numerical analysis of penetrometers free-falling into soil with shear strength increasing linearly with depth.” Computers and Geotechnics, 72, 57–66.
Meyerhof, G. G. (1961). The ultimate bearing capacity of wedge-shaped foundations. Proceedings of the 5th International Conference on Soil Mechanics and Foundation Engineering ICSMFE, Paris, 105–109.
Nazem, M., Carter, J., Airey, D., and Chow, S. (2012). “Dynamic analysis of a smooth penetrometer free-falling into uniform clay.” Géotechnique, 62(10), 893–905.
Omidvar, M., Iskander, M., and Bless, S. (2012). “Stress-strain behavior of sand at high strain rates.” International Journal of Impact Engineering, 49, 192–213.
Prezzi, M., Han, F., Ganju, E., and Salgado, R. (2018). “Effects of interface roughness, particle geometry, and gradation on the sand–steel interface friction angle.” Journal of Geotechnical and Geoenvironmental Engineering, 144(12). https://doi.org/10.1061/(ASCE)GT.1943-5606.0001990.
Stark, N. (2016). “Geotechnical Site Investigation in Energetic Nearshore Zones: Opportunities & Challenges.” Australian Geomechanics Journal, 51(4), 95–107.
Stark, N., Wilkens, R., Ernstsen, V. B., Lambers-Huesmann, M., Stegmann, S., and Kopf, A. (2012). “Geotechnical properties of sandy seafloors and the consequences for dynamic penetrometer interpretations: quartz sand versus carbonate sand.” Geotechnical and Geological Engineering,30(1), 1–14.
Stark, N., Hanff, H., and Kopf, A. (2009). “Nimrod: A tool for rapid geotechnical characterization of surface sediments.” Sea Technology, 50(4), 10–14.
Stoll, R. D., Sun, Y. F., and Bitte, I. (2007). Seafloor properties from penetrometer tests. IEEE Journal of Oceanic Engineering, 32(1): 57–63. doi:https://doi.org/10.1109/JOE.2007.890943.
Sulsky, D., Zhou, S., and Schreyer, H. L. (1995). “Application of a particle-in-cell method to solid mechanics.” Computer Physics Communications, 87, 236–252.
White, D. J., O’Loughlin, C. D., Stark, N., and Chow, S. H. (2018). “Interpretation of free fall penetrometer tests in sands: An approach to determining the equivalent static resistance.” Cone Penetration Testing 2018, 695–701.
Yalcin, F. F. (2021). Numerical Analysis of FFP Impact on Saturated Loose Sand. Master’s Thesis, Virginia Polytechnic Institute and State University, Blacksburg.
Yamamuro, J. A., Abrantes, A. E., and Lade, P. V. (2011). “Effect of Strain Rate on the Stress-Strain Behavior of Sand.” Journal of Geotechnical & Geoenvironmental Engineering, 137(12), 1169–1178.
Yerro, A. (2015). MPM modelling of landslides in brittle and unsaturated soils. Ph.D. thesis, Univeritat Politecnica de Catalunya, Univeritat Politecnica de Catalunya.
Zambrano-Cruzatty, L., and Yerro, A. (2020). “Numerical simulation of a free fall penetrometer deployment using the material point method.” Soils and Foundations, 60(3), 668–682. https://doi.org/10.1016/j.sandf.2020.04.002.
Zambrano-Cruzatty, L., Yerro, A., and Stark, N. (2020). “Influence of the Stiffness and Saturated Conditions of Sand on the Numerical Simulation of Free Fall Penetrometers.” Proc. Geo-Congress 2020. doi:https://doi.org/10.1061/9780784482803.002.
Information & Authors
Information
Published In
Geo-Congress 2023
Pages: 180 - 189
History
Published online: Mar 23, 2023
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.