Simplified slope reliability analysis considering spatial soil variability

Abstract Due to inherent spatial variability, soil properties vary from one location to another even within one soil layer. Such spatial variability of soils gives rise to scale-dependency in slope safety evaluation. This paper presents a simplified reliability method for slopes considering spatial soil variability. In this method, equivalent homogeneous random soil parameters are used in a single random variable (SRV) method (e.g., the first-order reliability method) to evaluate the slope reliability. Spatial variability is considered by using the equivalent parameters such that a SRV method with these equivalent parameters produces a comparable failure probability as that calculated using a more rigorous random finite element/difference method (RFEM/RFDM) with the original spatially variable parameters. Empirical equations for determining the statistics (mean value and standard deviation) of the equivalent parameters are derived through extensive RFDM analyses. The proposed method is found to be valid for both single-layered and two-layered slopes.

[1]  Kok-Kwang Phoon,et al.  Mean and Variance of Mobilized Shear Strength for Spatially Variable Soils under Uniform Stress States , 2014 .

[2]  Dian-Qing Li,et al.  Assessment of Slope Stability in the Monitoring Parameter Space , 2016 .

[3]  Suzanne Lacasse,et al.  Slope reliability analysis accounting for spatial variation , 2007 .

[4]  G. L. Sivakumar Babu,et al.  Effect of soil variability on reliability of soil slopes , 2004 .

[5]  Erik H. Vanmarcke,et al.  Random Fields: Analysis and Synthesis. , 1985 .

[6]  Lei Wang,et al.  Reliability-Based Design of Rock Slopes – A New Perspective on Design Robustness , 2013 .

[7]  Jianye Ching,et al.  Simplified reliability method for spatially variable undrained engineered slopes , 2013 .

[8]  Amit Srivastava,et al.  Influence of spatial variability of permeability property on steady state seepage flow and slope stability analysis , 2010 .

[9]  M. W. Bari,et al.  Three-dimensional finite element analysis of spatially variable PVD improved ground , 2015 .

[10]  Mark Cassidy,et al.  Probabilistic identification of soil stratification , 2016 .

[11]  D. V. Griffiths,et al.  Risk Assessment in Geotechnical Engineering , 2008 .

[12]  D. V. Griffiths,et al.  Bearing capacity of spatially random soil: the undrained clay Prandtl problem revisited , 2001 .

[13]  Steven L. Kramer,et al.  Geotechnical Characterization and Random Field Modeling of Desiccated Clay , 2012 .

[14]  Yu Wang,et al.  Probabilistic characterization of Young's modulus of soil using equivalent samples , 2013 .

[15]  Kok-Kwang Phoon,et al.  Random field characterisation of stress-normalised cone penetration testing parameters , 2005 .

[16]  Yu WangY. Wang,et al.  Practical reliability analysis of slope stability by advanced Monte Carlo simulations in a spreadsheet , 2011 .

[17]  Andrew J. Whittle,et al.  Effect of spatial variability on the slope stability using Random Field Numerical Limit Analyses , 2016 .

[18]  Yinghui Tian,et al.  Probabilistic combined loading failure envelopes of a strip footing on spatially variable soil , 2013 .

[19]  Gordon A. Fenton,et al.  Influence of spatial variability on slope reliability using 2-D random fields. , 2009 .

[20]  D. V. Griffiths,et al.  Influence of soil shear strength spatial variability on the compressive strength of a block , 2016 .

[21]  Yinghui Tian,et al.  Random finite element method for spudcan foundations in spatially variable soils , 2016 .

[22]  W. Tang,et al.  Efficient Spreadsheet Algorithm for First-Order Reliability Method , 2007 .

[23]  Dian-Qing Li,et al.  Slope reliability analysis considering spatially variable shear strength parameters using a non-intrusive stochastic finite element method , 2014 .

[24]  Gordon A. Fenton,et al.  SYSTEM RELIABILITY OF SLOPES BY RFEM , 2010 .

[25]  Kok-Kwang Phoon,et al.  Evaluation of Geotechnical Property Variability , 1999 .

[26]  Zhe Luo,et al.  Reliability analysis of basal-heave in a braced excavation in a 2-D random field , 2012 .

[27]  Sunny Ye Fang,et al.  First-Order Reliability Method for Probabilistic Liquefaction Triggering Analysis using CPT , 2006 .

[28]  Li Min Zhang,et al.  Characterizing geotechnical anisotropic spatial variations using random field theory , 2013 .

[29]  Hong-Xin Chen,et al.  Presenting regional shallow landslide movement on three-dimensional digital terrain , 2015 .

[30]  R. Chenari,et al.  Generating non-stationary random fields of auto-correlated, normally distributed CPT profile by matrix decomposition method , 2015 .

[31]  J BathurstRichard,et al.  Simplified probabilistic slope stability design charts for cohesive and cohesive-frictional (c-ϕ) soils , 2014 .

[32]  Yu Wang,et al.  Bayesian perspective on geotechnical variability and site characterization , 2016 .

[33]  S. M. Dasaka,et al.  Spatial variability of in situ weathered soil , 2012 .

[34]  A. Kiureghian,et al.  Second-Order Reliability Approximations , 1987 .

[35]  Xueyou Li,et al.  Using Conditioned Random Field to Characterize the Variability of Geologic Profiles , 2016 .

[36]  D. V. Griffiths,et al.  SLOPE STABILITY ANALYSIS BY FINITE ELEMENTS , 1999 .