DBPapers
DOI: 10.5593/SGEM2014/B12/S2.085

NUMERICAL ANALYSIS OF DRILLED DISPLACEMENT SYSTEM PILES

J. Stacho,E. Ladicsova
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-08-7 / ISSN 1314-2704, June 19-25, 2014, Book 1, Vol. 2, 665-672 pp

ABSTRACT
Drilled Displacement System (DDS) piles are an innovative technology for execution of pile foundations. DDS piles can be optimally designed in fine-grained soils and sandy soils where horizontal soil displacement is possible and causes increased pile resistance. Instrumented static load tests were carried out for verification of pile design by calculation. Tested piles were 16 to 18 m long with diameter of 410 mm. Loadsettlement curves and load distribution curves obtained by static load tests are compared with results of numerical modelling and analytical calculations. Geological conditions of the area consist of soft clays to depth more than 10 m below surface. Dense to very dense sands and gravels are located under the clays. Geotechnical software Plaxis was used for numerical analysis. Impact of technology which has a significant impact to pile resistance was taken into account by using Cavity Expansion Theory by Mecsi. The article presents parametric study where influence of pile-soil interface and impact of the technology are analysed. Calculated load-settlements curves are equal to results of static load tests with more than 95 % accuracy in all cases.

Keywords: drilled displacement system piles, numerical analysis, numerical modelling, pile foundations, static load test, cavity expansion theory