Geotechnical Characterization of Collapsible Salty Sands Subjected to Monotonic and Cyclic Loadings – A Case Study for Areas with High Seismicity

Geotechnical Characterization of Collapsible Salty Sands Subjected to Monotonic and Cyclic Loadings – A Case Study for Areas with High Seismicity

Journal: Soils and Foundations
Issue: Volume 63, Issue 1, February 2023
Authors: Jorge Macedo a, Gavi Sotelo b, Susana Orellana c, Luis Vergaray a, Fangzhou Liu d, Hamza Jaffal e, Chadi El Mohtar c

a School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
b Knight Pie´sold Consulting, Lima, Peru
c Department of Civil, Architectural, Environmental Engineering, University of Texas at Austin, Austin, TX, USA
d Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada
e Golder Associates Inc., Atlanta, GA, USA


Collapsible soils are typically found in arid regions and often have an aeolian or alluvial origin. In their natural states, they may have a low moisture content and cemented structure that can contribute to high strength and stiffness; however, wetting or saturation can reduce the strength and stiffness due to loss of the cementation. This paper presents a geotechnical characterization of collapsible salty sands in the highly seismic southern coast of Peru, which makes the characterization of their dynamic properties and expected response to earthquake-induced demands (e.g., liquefaction) of primary importance. The geotechnical characterization was performed on intact and remolded samples utilizing various field and laboratory tests, including oedometer, direct shear, static triaxial, cyclic simple shear, torsional resonant column, plate loading, and MASW tests. The results revealed insights on the geotechnical properties and mechanical response of collapsible soils and the effects of salt cementation. The results indicated: 1) a decreasing brittle and collapsible behaviors with decreasing cementation while maintaining consistent post-collapse residual strength; 2) oedometer and in situ plate loading tests showed a sudden increase in deformations once cementation is broken; 3) higher dilation potential of collapsible soils as compared to natural sands; 4) decrease in the maximum shear modulus due to the loss of cementation; 5) increase in the stress dependence of the maximum shear modulus with loss of cementation; and 6) a higher resistance to liquefaction for the collapsible soils, even after washing, as compared to natural sands, which may be ascribed to the more pronounced dilation potential.


Download the full paper.


Recent Insights

November 2023
Earthquake-induced Deformation Analysis of a TSF Undergoing Tailings Reprocessing
November 2023
Case Study: Approach to Determining the Risk Mitigation Priority of a Historic TSF in North America
October 2023
The Role of Sensitivity Analysis in Selecting Dam Breach Parameters
September 2023
Transición energética para gerentes de mina
August 2023
Interview: Guillermo Barreda, Gerente General, Knight Piésold Perú
July 2023
Selection of Soil Shear Strength Parameters Based on Integrated In Situ Tests, Lab Tests and Numerical Calibration Approach
June 2023
Leveraging Knowledge and Experience of a Well-Formed Independent Tailings Review Board to Enhance Tailings Facility Safety
May 2023
Is the Implementation of Dry Stacking for Tailings Storage Increasing? A Southern African Perspective
February 2023
Canadian Consulting Engineer's Lifetime Achievement Awards: Jeremy Haile
November 2022
Application of the 3D Limit Equilibrium Method in Tailings Dam Breach Analysis
November 2022
Evaluation of Tailings Behaviour for Dam Breach Assessments
November 2022
Tailings Improvement by Stress-Densification from Waste Rock Capping
November 2022
Transforming Tailings Management Systems toward Alignment with the GISTM: A Case History
October 2022
Managing Excessive Pit Wall Deformation of Weak Rock Mass
October 2022
State-of-the-art Method for Estimating Long-term Hydroclimatic Conditions for Tailing Dam Water Management and Dam Safety Planning
August 2022
Observed Subsidence Progression at New Afton Mine in Response to Lift 1 Mining
June 2022
Hydrometric Monitoring and Effluent Discharge Mixing in Challenging Natural Conditions
May 2022
Inundation Modelling of Non-Newtonian Tailings Dam Breach Outflows
May 2022
Video: Tailings Management Compliancy Picks Up Momentum