Abstract
Frequently, deep foundations extend through potentially liquefiable sand layers near the ground surface and bear on more competent layers at depth. When liquefaction occurs, the skin friction in the liquefied layer would be expected to decrease to some negligible value, but as the liquefiable layer settles, negative skin friction could potentially develop around the pile in this layer as effective stress increases. To investigate the loss of skin friction and the development of negative skin friction, axial load tests were performed on an instrumented full-scale tapered pile before and after blast-induced liquefaction at a site in Mirabello (Ferrara, Italy) that was affected by liquefaction following the 2012 Emilia earthquakes. The test pile was a 16.5 m long concrete pile with a diameter of 0.52 m at the head tapering to 0.26 m at the toe. Following blasting, liquefaction developed within a 6-m thick sand layer below a clay surface layer resulting in significant settlement. Skin friction in the liquefied layer initially dropped to essentially zero. However, as the liquefied sand reconsolidated, negative skin friction became equal to about 50% of the pre-blast ultimate positive skin friction. Negative skin friction in the overlying non-liquefied clay layer was only 80% of the ultimate positive skin friction. This is likely due to the surrounding soil moving slightly away from the tapered pile as the soil settled vertically downward. Despite significant ground settlement, pile settlement was relatively small because of the resistance provided by the toe of the pile.
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References
Boulanger, R.W., Brandenberg, S.J.: Neutral plane solution for liquefaction-induced down-drag on vertical piles. In: Geotech Engineering for Transportation Projects, pp. 470–478 (2004)
Fellenius, B.H., Siegel, T.C.: Pile drag load and downdrag in a liquefaction event. J. Geotech. Geoenviron. 134(9), 1412–1416 (2008)
Weaver, T.J., Ashford, S.A., Rollins, K.M.: Response of 0.6 m cast-in-steel-shell pile in liquefied soil under lateral loading. J. Geotech. Geoenviron. 131(1), 94–102 (2005)
Rollins, K.M., Gerber, T.M., Lane, J.D., Ashford, S.A.: Lateral resistance of a full-scale pile group in liquefied sand. J. Geotech. Geoenviron. 131(1), 115–125 (2005)
Wentz, F., van Ballegooy, S., Rollins, K.M., Ashford, S.A., Olsen, M.: Large scale testing of shallow ground improvements using blast-induced liquefaction. In: Proceedings of the 6th International Conference on Earthquake Geotechnical Engineering. New Zealand Geotechnical Society (2015)
Ashford, S.A., Rollins, K.M., Lane, J.D.: Blast-induced liquefaction for full-scale foundation testing. J. Geotech. Geoenviron. 130(8), 798–806 (2004)
Gallagher, P.M., Conlee, C.T., Rollins, K.M.: Full-scale field testing of colloidal silica grouting for mitigation of liquefaction risk. J. Geotech. Geoenviron. 133(2), 186–196 (2007)
Rollins, K.M., Strand, S.: Downdrag forces due to liquefaction surrounding a pile. In: Proceedings of the 8th US National Conference on Earthquake Engineering (2006)
Rollins, K.M., Strand, S.R., Hollenbaugh, J.E.: Liquefaction induced downdrag and dragload from full-scale tests. In: Iai, S. (ed.) Developments in earthquake geotechnics. Geotechnical, Geological and Earthquake Engineering, vol. 43, pp. 89–109. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-62069-5_5
Rollins, K.M., Hollenbaugh, J.: Liquefaction induced negative skin friction from blast-induced liquefaction tests with auger-cast piles. In: Proceedings of the 6th International Conference on Earthquake Geotechnical Engineering. New Zealand Geotechnical Society (2015)
Amoroso, S., Rollins, K.M., Lusvardi, C., Monaco, P., Milana, G.: Blast-induced liquefaction results at the silty-sand site of Mirabello, Emilia Romagna region, Italy. In: Geotechnical Earthquake Engineering and Soil Dynamics V, ASCE, p. 10 (2018)
Kevan, L., Rollins, K.M., Coffmann, R., Ishimwe, E.: Full-scale blast liquefaction testing in Arkansas USA to evaluate pile downdrag and neutral plane concepts. In: Silvestri, Moraci (eds.) Earthquake Geotechnical Engineering for Protection and Development of Environment and Constructions, pp. 648–655. Associazione Geotecnica Italiana, Rome, Italy (2019). ISBN 978-0-367-14328-2
Ishimwe, E., Coffman, R.A., Rollins, K.M.: Analysis of post-liquefaction axial capacities of driven pile and drilled shaft foundations. In: Proceedings of the IFCEE, pp. 272–283 (2018)
Lehane, B.M., Bittar, E., Lacasse, S., Liu, Z., Nadim, F.: New CPT methods for evaluation of the axial capacity of driven piles. In: Proceedings of the 5th International Conference on Cone Penetration Testing: (CPT 2022), pp. 3–15. CRC Press (2022)
API. ANSI/API RP 2GEO: Geotechnical and Foundation Design Considerations. ISO 19901-4:2003 (Modified), Petroleum and natural gas industries-Specific requirements for offshore structures, Part 4-Geotechnical and foundation design considerations. 1st edn. API Publishing Services, Washington, DC (2011)
Nordlund, R.L.: Point bearing and shaft friction of piles in sand. Presented at the 5th Annual Short Course on Fundamentals of Deep Foundations Design, University of Missouri-Rolla (2011)
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Rollins, K., Amoroso, S., Colella, V., Minarelli, L., Ure, D. (2023). Liquefaction-Induced Downdrag on Tapered Piles from Full-Scale Blast Liquefaction Tests. In: Ferrari, A., Rosone, M., Ziccarelli, M., Gottardi, G. (eds) Geotechnical Engineering in the Digital and Technological Innovation Era. CNRIG 2023. Springer Series in Geomechanics and Geoengineering. Springer, Cham. https://doi.org/10.1007/978-3-031-34761-0_32
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