Engineering Geology

Engineering Geology

Comparative Analysis of Probabilistic Slope Stability Analysis Using PLAXIS LE V21, GeoStudio 2024, and Slide2

Author
seyed ali asghari pari
Behbahan Khatam Alanbia University of Technology
10.22034/JEG.2026.20.1.1018843
Abstract
The present study systematically compares probabilistic slope stability analysis using three widely used geotechnical engineering software packages: PLAXIS LE V21, GeoStudio 2024 (SLOPE/W module), and Slide2. Given the critical importance of risk assessment and the inherent uncertainty in soil parameters, probabilistic analysis has emerged as an essential approach for quantifying uncertainties and calculating key metrics such as probability of failure and reliability index. This research evaluates the capabilities, accuracy, efficiency, and limitations of each software by performing identical analyses on three distinct scenarios (homogeneous soil, three-layered soil, and pseudo-static conditions) while employing ten common limit equilibrium methods. The results demonstrate that all three software packages are capable of conducting probabilistic analyses with acceptable accuracy; however, each offers distinct strengths: Slide2 is ideal for complex risk analyses due to its specialized tools and advanced graphical visualizations; GeoStudio is better suited for routine projects owing to its intuitive user interface and seamless integration with other modules; and PLAXIS LE excels in computationally demanding problems through its high numerical accuracy and hybrid finite element limit equilibrium (FELA) approach. This study provides practical guidance for engineers in selecting the most appropriate software based on project complexity, required accuracy, and available resources. It also emphasizes the advantages of probabilistic approaches over traditional deterministic analyses in effective risk management.
Keywords
Probability analysis
slope Stability
PLAXIS
GeoStudio
safety factor
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