Dynamic response of thickened tailings in shaking table testing

Area of Science:

• Geotechnical Engineering
• Environmental Engineering
• Mining Engineering

Background:

• Thickened tailings disposal is a key technology in modern mining for water management and land use.
• Understanding the dynamic behavior of layered thickened tailings is crucial for the stability of tailings storage facilities.

Purpose of the Study:

• To evaluate the dynamic response and liquefaction susceptibility of layered thickened tailings under cyclic loading.
• To investigate the influence of pore water pressure and migration on tailings behavior during seismic simulation.

Main Methods:

• An instrumented model of thickened tailings was subjected to dynamic loading using a shaking table.
• Cyclic loading with a peak horizontal acceleration of 0.13 g and frequency of 1 Hz was applied.
• Sensors monitored accelerations, displacements, volumetric water content, and pore water pressures within each tailings layer.

Main Results:

• The top tailings layer showed different acceleration patterns compared to the base and lower layers.
• All tailings layers exhibited initial contraction followed by dilation during shaking.
• Excess pore water pressure ratios exceeded unity in all layers post-shaking, indicating liquefaction potential.
• Observed upward and downward water migration within the tailings deposit.

Conclusions:

• Layered thickened tailings are susceptible to liquefaction under the tested dynamic loading conditions.
• Pore water migration significantly affects tailings stability, pore pressure, and displacement.
• Findings enhance the understanding of thickened tailings' dynamic behavior, crucial for safe and sustainable mining operations.