Investigation of Design Alternatives for a Piled Raft Case History
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 127, Issue 8
Abstract
This paper extends the design philosophy for piled rafts by exploring the factors that control the design of a published case history where the piled raft was instrumented. The case history studied differs from most published case histories in that concentrated column loads, rather than average “spread” loads, were considered in the foundation design. An extensive series of backanalyses was initially carried out with this case history, in order to calibrate the numerical program adopted herein. These analyses were followed by a parametric analysis for the evaluation of different design alternatives. These alternatives adopted distinctive pile characteristics (number, location, and length), which were varied for different raft thicknesses, yielding 26 different cases for cross comparison and comparison with the “reference” case history. Each of the solutions was also assessed in terms of relative costs against the reference case, allowing the establishment of conclusions of practical interest for those involved in the design of piled raft structures.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Burland, J. B., Broms, B. B., and de Mello, V. F. B. ( 1977). “Behaviour of foundations and structures.” Proc., 9th Int. Conf. on Soil Mech. and Found. Engrg., ISSMFE, Japan, Vol. 2, 495–546.
2.
Cunha, R. P., and Sales, M. M. ( 1998). “Field load tests of piled footings founded on a tropical porous clay.” Proc., 3rd Int. Geotech. Seminar Deep Found. on Bored and Auger Piles, ABMS, Brazil, Vol. 1, 433–438.
3.
Cunha, R. P., Small, J. C., and Poulos, H. G. ( 2000a). “Class C analysis of a piled raft case history in Gothenburg, Sweden.” Proc., Year 2000 Geotechnics—Geotech. Engrg. Conf., AIT, Thailand, Vol. 1, 271–280.
4.
Cunha, R. P., Small, J. C., and Poulos, H. G. ( 2000b). “Parametric analysis of a piled raft case history in Uppsala, Sweden.” Proc., 4th Seminar of Spec. Found. and Geotechnics, ABMS, Brazil, Vol. 2, 381–390.
5.
Fraser, R. A., and Wardle, L. J. ( 1976). “Numerical analysis of rectangular rafts on layered foundations.” Géotechnique, London, 26(4), 613–630.
6.
Hewitt, C. M. ( 1988). “Cyclic response of offshore pile groups.” PhD thesis, University of Sydney, Sydney, Australia.
7.
Mandolini, A., and Viggiani, C. ( 1997). “Settlement of piled foundations.” Géotechnique, London, 47(4), 791–816.
8.
Mindlin, R. D. ( 1936). “Force at a point in the interior of a semi-infinite solid.” Physics, 7.
9.
O'Neill, M. W., Caputo, V., De Cock, F., Hartikainen, J., and Mets, M. ( 1996). “Case histories of pile-supported rafts.” Rep., University of Houston, Houston.
10.
Poulos, H. G. ( 1990). “DEFPIG user's guide.” Ctr. for Geotech. Res., University of Sydney, Sydney, Australia.
11.
Poulos, H. G. ( 1998). “The pile-enhanced raft—An economical foundation system.” Keynote Lecture, Proc., 11th Brazilian Congr. on Soil Mech. and Geotech. Engrg., ABMS, Brazil, Vol. 4, 27–43.
12.
Poulos, H. G., and Small, J. C. ( 1998). “GARP6 user's manual.” Coffey Partners International Pty. Ltd, Sydney, Australia.
13.
Poulos, H. G., Small, J. C., Ta, L. D., Sinha, J., and Chen, L. ( 1997). “Comparison of some methods for analysis of piled rafts.” Proc., 14th Int. Conf. on Soil Mech. and Found. Engrg., ISSMFE, Germany, Vol. 2, 1119–1129.
14.
Randolph, M. F., and Clancy, P. ( 1993). “Efficient design of piled rafts.” Proc., 2nd Int. Geotech. Seminar Deep Found. on Bored and Auger Piles, U. Ghent, Belgium, Vol. 1, 119–130.
15.
Sales, M. M., Cunha, R. P., Farias, M. M., Small, J. C., and Poulos, H. G. ( 2000). “Comparisons of some programs analysing classical piled raft problems.” Proc., Year 2000 Geotechnics—Geotech. Engrg. Conf., AIT, Thailand, Vol. 1, 317–326.
16.
Sales, M. M., Cunha, R. P., and Jardim, N. A. ( 1999). “Analysis of piled footing tests on a tropical porous clay.” Proc., 11th PanAmerican Conf. on Soil Mech. and Geotech. Engrg., ABMS, Brazil, Vol. 3, 1395–1402.
17.
Sinha, J., and Poulos, H. G. ( 1997). “Piled raft foundation systems in swelling and shrinking soils.” Proc., 14th Int. Conf. on Soil Mech. and Found. Engrg., ISSMFE, Germany, Vol. 2, 1141–1144.
18.
Ta, L. D., and Small, J. C. ( 1996). “Analysis of piled raft systems in layered soils.” Int. J. Numer. and Analytical Methods in Geomech., 20, 57–72.
19.
Van Impe, W. F., and Lungu, I. ( 1996). “Technical report on settlement prediction methods for piled raft foundation.” Rep., University of Ghent, Ghent, Belgium.
20.
Yamashita, K., Kakurai, M., and Yamada, T. ( 1994). “Investigation of a piled raft foundation on stiff clay.” Proc., 13th Int. Conf. on Soil Mech. and Found. Engrg., ISSMFE, India, Vol. 2, 543–546.
21.
Yamashita, K., Yamada, T., and Kakurai, M. ( 1998). “Simplified method for analysing piled raft foundations.” Proc., 3rd Int. Geotech. Seminar Deep Found. on Bored and Auger Piles, U. Ghent, Belgium, Vol. 1, 457–464.
Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 127 • Issue 8 • August 2001
Pages: 635 - 641
History
Received: Apr 19, 2000
Published online: Aug 1, 2001
Published in print: Aug 2001
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.