Application of Stochastic Finite-Element Method to Deflection Analysis of Pavement Structures

Abstract

The effect of random variations in layer properties of a pavement-subgrade system on surface deflections is investigated. This is done by using a stochastic finite-element framework based on the perturbation method. The Taylor's expansion scheme is used. The variations of the surface deflections are related to the variations of layer moduli via a coefficient matrix, thereby allowing an investigation of the sensitivity of measured deflections to the variation of pavement and subgrade moduli. The analyses confirm that surface deflections are not very sensitive to variations of modulus within the pavement structure. Using the Boussinesq-Odemark approximation, it is concluded that, for the sample problem analyzed, the effect of higher-order terms on variation estimates of displacement is negligible when the coefficient of variation of subgrade modulus is less than 15 percent. The effect of inertia on the coefficient of variation of displacement due to variations in layer moduli is also briefly addressed. It is demonstrated that the variation in displacement under the load is sensitive to both the loading frequency and the equivalent mass of the pavement-subgrade system, particularly in the vicinity of the natural frequency of the system.

Get full access to this article

View all access options for this article.

References

Kleiber

, and Hein

T. D.

. The Stochastic Finite Element Method: Basic Perturbation Technique and Computer Implementation. John Wiley and Sons, Inc., Chichester, England, 1992.

Brzakala

, and Pula

. Neumann Expansion in the Stochastic Finite Element Method. Internal report. Institute of Geotechnics and Hydrotechnics, Technical University of Wroctaw, Poland, 1992.

Ghanem

R. G.

, and Spanos

P. D.

. Stochastic Finite Element: A Spectral Approach. Springer-Verlag, Inc., New York, 1991.

Siddharthan

, Sebaaly

P. E.

, and Javaregowda

. Influence of Statistical Variation in Falling Weight Deflectometers on Pavement Analysis. In Transportation Research Record 1377, TRB, National Research Council, Washington, D.C., 1992, pp. 57–66.

Lytton

R. L.

Backcalculation of Pavement Layer Properties. In Nondestructive Testing of Pavement and Backcalculation of Moduli, ASTM STP 1026 ( Bush

A. J.

III , and Baladi

G. Y.

, eds), American Society for Testing and Materials, Philadelphia, Pa., 1989, pp. 7–38.

Stolle

D. F. E.

Analysis and Interpretation of Falling Weight Deflec-tometer Data. Project 21230. Ontario Ministry of Transportation, Toronto, Canada, 1992.

Stolle

D. F. E.

, and Jung

F. W.

. Simplified, Rational Approach to Falling Weight Deflectometer Data Interpretation. In Transportation Research Record 1355, TRB, National Research Council, Washington, D.C., 1992, pp. 82–89.

Taylor

J. R.

An Introduction to Error Analysis. Oxford University Press, 1982.

Brzakala

, and Pula

. Stochastic Finite Element Method in a Settlement Analysis. In Numerical Models in Geomechanics (Pande and Pietruszczk, eds), Balkema, Rotterdam, Netherlands, 1992.

10.

Peiravian

Interpretation of In-Situ Pavement Properties Using FWD Testing Technique. Master's thesis. McMaster University, Hamilton, Ontario, Canada, 1994.