Coupled systems mechanics

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Parametric study on flexible footing resting on partially saturated soil

  • Singh, Mandeep (Department of Civil Engineering, Indian Institute of Technology Roorkee) ;
  • Sawant, V.A. (Department of Civil Engineering, Indian Institute of Technology Roorkee)
  • Received : 2014.06.01
  • Accepted : 2014.06.24
  • Published : 2014.06.25
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Abstract

Coupled finite element analysis is carried out to study the effect of degree of saturation on the vertical displacements and pore water pressures simultaneously by developing a FORTRAN90 code. The finite element formulation adopted in the present study is based upon Biot's consolidation theory to include partially saturated soils. Numerical methods are applied to a two-dimensional plane strain strip footing (flexible) problem and the effect of variable degree of saturation on the response of excess pore water pressure dissipation and settlement of the footing is studied. The immediate settlement in the case of partly saturated soils is larger than that of a fully saturated soil, the reason being the presence of pore air in partially saturated soils. On the other hand, the excess pore water pressure for partially saturated soil are smaller than those for fully saturated soil.

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References

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