M. Vafaeian,
Volume 22, Issue 1 (7-2003)
Abstract
A finite element program based on elastic –plastic model of Mohr-Coulomb criterion was used to evaluate the bearing capacity coefficients of soil under shallow strip flexible footing . The results were compared with others’ analytical results and it was found that the present study could offer quite consistent and rather precise values for the bearing capacity coefficients .
The effect of different parameters such as E , υ, φ ,ψ ,γ , type of mesh idealization ,type of elements ,type of load distribution at the footing base have been examined and some new results obtained and discussed. The main conclusion can be summarized as : that the values of bearing capacity coefficients for any particular amount of friction angle should not be expressed as a single number solely dependent on the friction angle ,but the accurate values must be considered as the values dependent on some other effective parameters , which have been mentioned above .
Keywords : soil bearing capacity , finite element , Mohr-Coulomb , shallow footing
R. Salamat Mamakani , A. Azhari,
Volume 40, Issue 2 (1-2022)
Abstract
Dynamic stability and liquefaction of tailings dams are great concerns for geotechnical engineers. In this study, the seismic response of the Esphordi mine tailing dam located in Bafgh seismic region of Yazd province is investigated. A finite-difference code (FLAC2D) is used to model the seismic liquefaction applying two constitutive criteria, namely Mohr-Coulomb and Finn-Byrne. For this purpose, a fish function is implemented into the code to simulate the non-linear elasto-plastic Finn-Byrne constitutive model. Horizontal and vertical displacements (subsidence) in the dam body, additional pore pressure, failure zones, and liquefaction due to seismic load were determined using the two selected criteria under the seismic load of the 6.4 magnitude earthquake occurred in 2005. Considering the type of behavioral model, Mohr-Coulomb and Finn-Byrne, the maximum horizontal displacement of 5 and 35 cm in the dam body and downstream, and subsidence of 4 and 23 cm at the dam crest and upstream are observed, respectively. Also, the calculated ratio of excess pore pressure (Ru), for both criteria, was less than the liquefaction limit (0.9), the maximum value of which was 0.7 for the Finn-Byrne criterion and 0.2 for the Mohr-Coulomb criterion. In general, the results show that considering the cumulative effect of the seismic load cycles in the Finn- Byrne model, this criterion provides a better understanding of the liquefaction phenomenon.
