Abstract

In this work, a quantitative uncertainty estimation of the random distribution of the soil material properties to the probability density functions of the failure load and failure displacements of a shallow foundation loaded with an oblique load is portrayed. A modified Cam Clay yield constitutive model is adopted with a stochastic finite element model. The random distribution of the reload path inclination κ, the critical state line inclination c of the soil and the permeability k of the Darcian water flow relation, has been assessed with Monte Carlo simulations accelerated by using Latin hypercube sampling. It is proven that both failure load and failure displacements follow Gaussian normal distribution despite the excessive non-linear behaviour of the soil. In addition, as the obliquity increases the mean value of failure load and the failure displacement always increases. The uncertainty of the output failure stress with the increase of the obliquity of the load remains the same. The failure spline of clays can be calculated within an acceptable accuracy with the proposed numerical scheme in every possible geometry and load conditions, considering the obliquity of the load in conjunction with non-linear constitutive relations.

Highlights

  • The ultimate load of footing settlements and the subsequent displacements and material states is an area of significant concern in the field of geomechanics

  • In porous random field simulations, the greatest coefficient of variation (CoV) of the shallow foundation total load is 48% the input uncertainty, while for the displacements the reduction of the variability is by 40% and 56% for the vertical and horizontal displacement, respectively

  • The variability estimation of the failure of shallow foundations on cohesive soils taking into account the pore pressure soil interaction with the use of the stochastic finite element method is depicted

Read more

Summary

Introduction

The ultimate load of footing settlements and the subsequent displacements and material states is an area of significant concern in the field of geomechanics. A numerical simulation scheme with a modified Cam Clay material yield model proposed in [31] is implemented, which is an accurate and valid quantitatively material for cohesive soil simulation [32] This material yield surface with the incorporation of a finite element model can estimate the real load and displacement field in every possible 3D loading conditions. The spatial distributions of the material parameters with respect to the depth of the soil domain are the linear, the constant variation and the random field process, formulated from the Karhunen–Loeve series expansion adopting an exponential autocorrelation function. The eccentricities of the shallow foundation in X and Y directions and correlation lengths are parametrized and compared to the analogous solid problem in which the pore pressure is neglected

Dynamic Soil–Pore–Fluid Interaction
The Karhunen–Loeve Series and the Truncated Normal Variables
Description of the Problem
Limit Stresses–Strains and Failure Spline
Findings
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call