Abstract
The inability to evaluate the effects of the various uncertainties due to spatial and material variability of the soil and pile properties in the axial load capacity of a pile foundation had led some designers to adopt higher global factors of safety in design, which may be conservative and uneconomical if it were not properly evaluated. In addition, the use of lower factors of safety in pile design is often traditionally justified only by the performance of specific pile load tests. This study presents the application of probabilistic analysis based on Stochastic Finite Element Method (SFEM) and Monte Carlo Simulation (MCS) in the selection of economical factors of safety for the geotechnical design of pile axial load capacity. The SFEM is implemented by a coupling between the reliability algorithm with the MCS technique in MATLAB® and the OpenSees finite element program. A probabilistic method of pile analysis evaluates the risk, reliability, or probability of failure associated with the selection of lower factors of safety in design. The results of a probabilistic method of pile capacity evaluation then provide guidance in the selection of a more reliable, unconservative, and economical factor of safety at an acceptable level of risk by making cost comparisons with available options for design.
Similar content being viewed by others
References
Boulanger, R. W. (2003a). The TzSimple1 Material. http://opensees.berkeley.edu/.
Boulanger, R. W. (2003b). The QzSimple1 Material. http://opensees.berkeley.edu/.
Brandenberg, S. (2004). TzSimple1Gen Command. http://opensees.berkeley.edu/.
Coyle, H. M. and Reese, L. C. (1966). “Load transfer for axially loaded piles in clay.” Journal of Soil Mechanics and Foundations Division, ASCE, Vol. 9,SM 2, pp. 1–26.
Das, B. M. (2004). Principles of foundation engineering, 5th ed., Brooks/Cole-Thomson Learning, Inc., USA.
Fenton, G. A. and Griffiths, D. V. (2007). “Reliability based deep foundation design.” Proceedings of GeoDenver2007: New peaks in Geotechnics, ASCE, Reston. Paper No. GSP 170.
Filippas, O. B., Kulhawy F. H., and Grigoriu M. D. (1988). Reliabilitybased foundation design for transmission line structures: uncertainties in soil property measurement, Report EL-5507(3), Electric Power Research. Institute, Palo Alto.
Gannon, J. A., Masterton, G. G. T., Wallace, W. A., and Muir Wood, D. (1999). Pile foundations in weak rock, Report No. 181, Construction Industry Research and Information Association (CIRIA), London, UK.
Haldar, A. and Mahadevan, S. (2000). Probability, reliability and statistical methods in engineering design, Wiley, New York (USA).
Haldar, S. and Babu, G. L. S. (2007). “Ultimate capacity of pile foundation on spatially random cohesive soil.” Proc. 10 th International Conference on Applications of Statistics and Probability in Civil Engineering, Tokyo, Japan
Hu, J., Haldar, A., Kwak, K., and Park, J. (2008). “Probabilistic reliability estimation of an axially loaded pile.” Proc. 12 th International Conference of International Association for Computer Methods and Advances in Geomechanics (IACMAG), Goa, India, October 1–6, pp. 1811–1817.
Kim, H. J. and Mission, J. L. (2009). “Negative skin friction on piles based on finite strain consolidation theory and the nonlinear load transfer method.” KSCE Journal of Civil Engineering, Vol. 13, No. 2, pp. 107–115.
Kim, H. J., Mission, J. L., and Park, I. S. (2007). “Analysis of static axial load capacity of single piles and large diameter shafts using nonlinear load transfer curves.” KSCE Journal of Civil Engineering, Vol. 11, No. 6, pp. 285–292.
Kim, S. N. (2002). “Probabilistic analysis of settlement for a floating foundation on soft clay.” KSCE Journal of Civil Engineering, Vol. 6, No. 3, pp. 235–241.
Lacasse, S. and Nadim, F. (1996). “Uncertainties in characterizing soil properties.” Proc. Uncertainty in the Geologic Environment: From Theory to Practice, ASCE GSP 58, Vol. 1, pp. 49–75.
Lee, J. S. and Park, Y. H. (2008). “Equivalent pile load-head settlement curve using a bi-directional pile load test.” Computers and Geotechnics, Vol. 35, pp. 124–133.
Likins, G. E. (2004). “Pile testing — selection and economy of safety factors.” Current Practices and Future Trends in Deep Foundations, Geotechnical Special Publication No. 125, DiMaggio, J. A., and Hussein, M. H., Eds, American Society of Civil Engineers: Reston, VA, pp. 239–252.
MATLAB®. The MathWorks, Inc. (www.mathworks.com).
Mazzoni, S., McKenna, F., Scott, M. H. et al. (2006). OpenSees Command Language Manual. http://opensees.berkeley.edu/.
Meyerhof, G. (1970). “Safety factors in soil mechanics.” Canadian Geotechnical Journal, Vol. 7, No. 4, pp. 349–355.
Misra, A. and Roberts, L. (2006). “Probabilistic analysis of drilled shaft service limit state using the ‘t-z’ method.” Canadian Geotechnical Journal, Vol. 43, No. 12, pp. 1324–1332.
Mosher, R. L. (1984). Load transfer criteria for numerical analysis of axially loaded piles in sand — Part 1: Load-transfer criteria, Technical Report K-84-1, US Army Engineering Waterways Experimental Station, Mississippi.
OpenSees (2000). Open System for earthquake engineering simulation, Pacific Earthquake Engineering Research Center, University of California, Berkeley, California, http://opensees.berkeley.edu/.
Phoon, K. K. and Kulhawy, F. H. (1996). “On quantifying inherent soil variability.” Proc. Uncertainty in the Geologic Environment: From Theory to Practice, ASCE GSP 58, Vol. 1, pp. 326–340.
Phoon, K. K. (2008). Reliability-based design in geotechnical engineering: computations and applications, Taylor & Francis, London.
Pile Driving Contractors Association (PDCA) (2001). Recommended design specifications for driven bearing piles, PDCA, Boulder, CO.
Reese, L. C. and O’Neill, M. W. (1987). Drilled shafts: Construction procedures and design methods, Report No. FHWA-HI-88-042, US Department of Transportation, Federal Highway Administration, Virginia.
Reese, L. C., Hudson, W. R., and Vijayvergiya, V. N. (1969). “An investigation of the interaction between bored piles and soil.” Proc. 7 th Int. Conf. Soil Mech., Mexico, Vol. 2, pp. 211–216.
Stefanou, G. (2009). “The stochastic finite element method: past, present, and future.” Computer Methods in Applied Mechanics and Engineering, Vol. 198, No. 9–12, pp. 1031–1051.
USACE Engineering and Design Manual (1991). Design of pile foundations, EM 1110-2-2906, US Army Corps of Engineers, Washington, DC.
Wright, S. J. (1977). Limit-state design of drilled shafts, MS Thesis, The University of Texas at Austin, Texas, p. 148.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kim, HJ., Mission, J.L. Probabilistic evaluation of economical factor of safety for the geotechnical design of pile axial load capacity. KSCE J Civ Eng 15, 1167–1176 (2011). https://doi.org/10.1007/s12205-011-0948-8
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12205-011-0948-8