PROBABILISTIC SETTLEMENT ANALYSIS OF STRIP FOOTING ON SPATIALLY RANDOM SOIL

  • RIZGAR H. AHMED
  • MOHAMMED S. HUSSAIN
Keywords: Foundation settlement; Spatially random soil; Probabilistic analysis; Random Finite element method

Abstract

The prediction of settlement in a traditional design approach usually uses a deterministic value of
modulus of elasticity (E), which is estimated as an average value by testing the soil at selected locations.
However, these deterministic properties of soil may not represent the actual properties of soil and site
condition. Due to numerous sources of uncertainty, the properties of soil mass are spatially varying and
anisotropic in the natural field condition. In this study, a random finite element method (RFEM) is used to
evaluate the reliability of settlement of the strip footing on spatially random soil. Modulus of elasticity is
the only considered random parameter. For this purpose, 2000 spatially random realizations of E-field are
generated using Monte Carlo Simulation. Each of these realizations of heterogeneous soil profile is passed
to FEM to analyze the settlement of footing. The final settlement results measured in all these realizations
are then statistically evaluated and compared. The results of analysis show that the mean and standard
deviation of the footing settlement are increased with increasing spatial correlation length. The large value
of isotropic correlation length led to an increase in the mean settlement value by more than 25% as
compared with the deterministic settlement calculations. Also, it is concluded that the rate of increase of
settlements for anisotropic correlation length is lower than the one under isotropic condition.

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Author Biographies

RIZGAR H. AHMED

Dept. of Civil Engineering, College of Engineering, University of Duhok, Kurdistan Region-Iraq

MOHAMMED S. HUSSAIN

Dept. of Civil Engineering, College of Engineering, University of Duhok, Kurdistan Region-Iraq

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Published
2021-01-06
How to Cite
AHMED, R. H., & HUSSAIN, M. S. (2021). PROBABILISTIC SETTLEMENT ANALYSIS OF STRIP FOOTING ON SPATIALLY RANDOM SOIL. Journal of Duhok University, 23(2), 617-629. https://doi.org/10.26682/csjuod.2020.23.2.48