Influence of time on the bearing capacity of precast piles

• Autorzy: Gwizdała K. , Więcławski P.

Identyfikatory

DOI

10.2478/sgem-2013-0037

• Języki publikacji: EN

Abstrakty

EN

One of the most popular types of foundations in layered subsoil with very differentiated soil shear strengths are precast piles. One of the reasons is the fact that we can well control the driving process during the installation of these piles. The principles of the assessment of bearing capacity and settlements of the piles given by Eurocode 7, concentrate on two main methods, i.e., Static Pile Load Tests (SPLT) and Dynamic Driving Analysis (PDA). However, the evaluation of real load-settlement curve for piles being driven in layered subsoil, where non- cohesive and cohesive soils occur alternately, is neither easy nor straightforward. In the paper, the results of both SPLT and PDA tests for objects on the highways in Poland are presented. Field investigations carried out at various time points since the installation of piles (from 7 to 90 days) revealed an increase of bearing capacity with time. The reason for this may be a change of the soil state near the piles due to their driving (displacement of piles) as well as a change of microstructure at the contact between soil and pile shaft. The results of load tests were referred to the geotechnical parameters of the subsoil, which was recognized by means of traditional borings and CPTU tests. The results of tests allow phenomena occurring with time to be assessed and bearing capacity of precast piles to be predicted.

Słowa kluczowe

EN

bearing capacity; precast pile; Eurocode 7

PL

pale fundamentowe; pale prefabrykowane; nośność pali; nośność graniczna; Eurokod 7

• Wydawca: De Gruyter
• Czasopismo: Studia Geotechnica et Mechanica
• Rocznik: 2013
• Tom: Vol. 35, nr 4
• Strony: 65--74
• Opis fizyczny: Bibliogr. 14 poz., rys.

Twórcy

autor

Gwizdała K.

• Gdańsk University of Technology, Department of Geotechnics, Geology and Maritime Engineering, Gdańsk, Poland

autor

Więcławski P.

• Gdańsk University of Technology, Department of Geotechnics, Geology and Maritime Engineering, Gdańsk, Poland

Bibliografia

• [1] GWIZDAŁA K., KOWALSKI J.R., Driven precast piles, (in Polish), PG WILiŚ KG, 2005.
• [2] GWIZDAŁA K., Pile foundations. Investigations and application, (in Polish), Vol. 2, PWN, 2013.
• [3] GWIZDAŁA K., Polish design methods for single axially loaded piles. Design of Axially Loaded Piles, European Practice, ERTC3 Brussels, Belgium, 17–18 April 1997.
• [4] CICHY L., TKACZYŃSKI G., RYBAK J., Dynamic tests of bearing capacity of precast piles, (in Polish), Inżynieria i Budownictwo, nr 3/2009.
• [5] KUMOR M.K., SZPAKOWSKI K., The bearing capacity of piles on expansive tertiary clays in the poligone condition, Silesian Technical University, Zeszyty Naukowe, No. 15, 2003.
• [6] ZADROGA B., Time dependent increase of bearing capacity of piles driven into cohesive soils, Archives of Hydroengineering, No. 3–4/1993.
• [7] SKOV R., DENVER H., Time-dependence of bearing capacity of piles, Proc. 3rd Int. Conf. on Application of Stress-wave Theory to Piles, Ottawa, Canada, 25–27 May 1988.
• [8] SKOV R., SVINKIN M.R., Set-up effect of cohesive soils in pile capacity, Proc. 6th Int. Conf. on Application of Stress-wave Theory to Piles, Sao Paulo, Brazil, 11–13 September 2000.
• [9] SOBALA D., Driven precast reinforced concrete piles, (in Polish), Aarsleff Sp. z o.o., 2010.
• [10] DE COCK F., LEGRAND C., HUYBRECHTS N., Overview of design methods of axially loaded piles in Europe – Report of ERTC3 – Piles, ISSMGE Subcommittee, XIII-th European Conference of Soil Mechanics and Geotechnical Engineering, Prague, Czech Republic, 25–28 August 2003.
• [11] PN-83/B-02482, Bearing capacity of pile and pile foundations.
• [12] EN 1997 (2004). Eurocode 7. Geotechnical design.
• [13] PN-EN 1997-1:2004, Eurokod 7: Projektowanie geotechniczne – Część 1: Zasady ogólne.
• [14] EN 12699:2001, Execution of special geotechnical works. Displacement piles.