A simplified method for calculating the reliability of rockfill dams slope stability using nonlinear parameters

Area of Science:

• Geotechnical Engineering
• Rockfill Dam Stability
• Reliability Analysis

Background:

• Slope stability analysis in geotechnical engineering relies on granular material strength.
• Non-linear shear strength characteristics of granular materials complicate reliability index calculations, requiring numerous iterations and partial derivatives.
• Existing methods for rockfill dams face computational challenges due to non-linear parameters.

Purpose of the Study:

• To propose an optimized algorithm for linearizing Duncan's non-linear strength parameters in slope reliability analysis.
• To enhance the efficiency of iterative methods for calculating reliability indices in rockfill dams.
• To verify the accuracy and feasibility of the proposed linearisation approach for practical applications.

Main Methods:

• Expansion of Duncan's non-linear strength model using Taylor series expansion.
• Derivation of a relationship between non-linear (Duncan's) and linear (Mohr-Coulomb) strength parameters.
• Implementation of the linearisation algorithm into the STAB computer program for analysis.
• Verification on a simplified slope and application to the Shuang Jiang Kou Dam.

Main Results:

• The linearisation algorithm accurately approximates non-linear strength parameters.
• Application to the Shuang Jiang Kou Dam showed linearized parameters yield comparable reliability indices to non-linear parameters.
• The proposed method significantly reduces computational complexity and iterations.

Conclusions:

• The proposed linearisation algorithm is a feasible and efficient approach for reliability analysis of rockfill dams.
• This method simplifies the calculation of reliability indices, making it more accessible for geotechnical engineers.
• The study demonstrates the practical applicability of the linearisation technique in real-world dam engineering projects.