Effect of Footing Roughness on Lower Bound Nγ Values

The bearing capacity factor Nγ was computed for a strip footing by considering the variation of footing-soil interface friction angle (δ) . The study follows a lower bound limit analysis in conjunction with finite elements and linear programming. The variation of Nγ with δ was obtained for different soil friction angles. The magnitude of Nγ increases significantly with the increase in δ . For δ=0 , the normal stress along the footing-soil interface was found to increase almost linearly with the increase in the distance from the footing edge. However, with the increase in δ , the location of the peak normal stress shifts gradually away from the center of the footing. The size of the plastic zone in relation to the footing width becomes gradually larger for greater values of δ . With respect to variation in δ , the obtained values of Nγ were found to be generally smaller than the results available in the literature.

[1]  C. F. Lee,et al.  A numerical study of the bearing capacity factor Nγ , 2001 .

[2]  Emmanuel M Detournay,et al.  Limit load in translational failure mechanisms for associative and non-associative materials , 1993 .

[3]  Radoslaw L. Michalowski,et al.  AN ESTIMATE OF THE INFLUENCE OF SOIL WEIGHT ON BEARING CAPACITY USING LIMIT ANALYSIS , 1997 .

[4]  Andrew J. Whittle,et al.  Calculations of Bearing Capacity Factor Nγ Using Numerical Limit Analyses , 2003 .

[5]  D. M. Dewaikar,et al.  Computation of Bearing Capacity Factor Nγ—Terzaghi’s Mechanism , 2003 .

[6]  George Geoffrey Meyerhof,et al.  Some recent research on the bearing capacity of foundations , 1963 .

[7]  Scott W. Sloan,et al.  Lower bound limit analysis using finite elements and linear programming , 1988 .

[8]  Wai-Fah Chen.  Limit Analysis and Soil Plasticity , 1975 .

[9]  K. Terzaghi.  Theoretical Soil Mechanics , 1943 .

[10]  Malcolm D. Bolton,et al.  Vertical bearing capacity factors for circular and strip footings on Mohr–Coulomb soil , 1993 .

[11]  Wai-Fah Chen,et al.  Limit analysis in soil mechanics , 1990 .

[12]  Harvey J. Burd,et al.  Numerical studies of bearing-capacity factor Nγ , 1997 .

[13]  Scott W. Sloan,et al.  Numerical limit analysis solutions for the bearing capacity factor Nγ , 2005 .

[14]  J. Kumar,et al.  Effect of footing—soil interface friction on bearing capacity factor Nγ , 2004 .

[15]  Abdul-Hamid Soubra,et al.  Upper-Bound Solutions for Bearing Capacity of Foundations , 1999 .

[16]  J. Pastor,et al.  Finite element method and limit analysis theory for soil mechanics problems , 1980 .

[17]  Jyant Kumar,et al.  Effect of Footing Roughness on Bearing Capacity Factor Nγ , 2007 .