Pile optimization in slope stabilization by 2D and 3D numerical analyses

ABSTRACT

In this paper, numerical computations using PLAXIS 2D and 3D have been conducted to optimize a row of piles in cohesive-frictional slope stabilization. First, 2D parametric studies were performed to identify both the optimal location and length of the pile as well as the effect of pile head conditions. Next, more rigorous parametric studies taking account of the exact geometry was carried out using 3D analyses. According to the obtained results, the fixed pile head located at the slope middle better improves the stability and reduces the optimal length of the pile. Piles with free head contribute marginally to the increased factor of safety of cohesive-frictional slope. In 3D analyses, it is shown that spacing ratio beyond S/D = 4 (S: pile spacing, D: diameter of the pile) , the soil will flow between piles leading to a total vanish of the arching effect when S/D exceeds 12. Comparing the results, the limitation of 2D analysis for piled cohesive-frictional slope is highlighted.

KEYWORDS:

• Lope stabilization
• finite element analysis
• factor of safety
• optimal location
• optimal spacing
• optimal length

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Mohamed Amine Benmebarek

Mohamed Amine Benmebarek is a PhD student at Department of Structural and Geotechnical Engineering Széchenyi István University Egyetemtér 1, Gyor Hungary. His research interests include slope stability analysis, numerical modeling, discrete element model, pile behavior and grain crushing.

Sadok Benmebarek

Sadok Benmebarek is Professor and laboratory director at Biskra University, Algeria. After his PhD research at the University of Constantine (Algeria) and INSA de Lyon (France), he has been involved in geotechnical research, consulting and education for more than 20 years. His research interests include soil-structure interaction, numerical modeling of geomaterials, underground construction, dams, stone columns, geosynthetic soil reinforcement and shallow foundations.

Majid Movahedi Rad

Majid Movahedi Rad obtained his PhD degree in civil engineering Budapest University of Technology and Economics in 2011 and his  habilitation in Széchenyi István University, Hungary in 2019. His research interests include Elastic-plastic optimal design of structures, structural dynamics, discrete element model.

Richard Ray

Richard Ray is Professor and laboratory director at Department of Structural and Geotechnical Engineering Széchenyi István University Egyetemtér 1, Gyor Hungary. After his MSE and PhD  in Civil Engineering at University of Michigan, he has been involved in geotechnical research, consulting and education for more than 38 years. His research interests include earthquake engineering; laboratory testing for dynqmic soil properties and field studies of contaminated sites.