πŸ“‹ Case Study

Limestone Quarry Slope Stabilization

Progressive bench failure due to bedding plane sliding and groundwater infiltration

πŸ—οΈ Project Overview

Michigan Limestone & Chemical Company, USA β€” 120 m high quarry wall

🎯 Challenge

Progressive bench failure due to bedding plane sliding and groundwater infiltration

πŸ”§ Design Approach

Drainage blanket + horizontal drains + toe buttressing + selective bench scaling and meshing

πŸ“ Design Diagram

Drainage Blanket Horiz. Drains Toe Buttress Bench Scaling & Meshing GW Infiltration c + σₙ tanφ = 125 kPa FS (Bishop) = 1.28 Limestone Quarry Slope Stabilization Bedding Plane Drainage/Mesh Horizontal Drains Toe Buttress

AI-generated project design illustration

πŸ“ Key Calculations

Shear Strength along Bedding Plane

c + Οƒβ‚™ tan Ο†
Result: 125 kPa
Determines interlayer sliding resistance

Factor of Safety (Bishop Method)

Ξ£(cΒ·l + (W βˆ’ uΒ·l)tanΟ†)/Ξ£(WΒ·sinΞ±)
Result: 1.28
Minimum acceptable FS = 1.3 for active slopes

πŸ“Š Results

Stabilized slope with FS >1.4; eliminated unplanned shutdowns; extended quarry life by 8 years

πŸ’‘ Lessons Learned

  • β€’Hydrogeological mapping is as critical as geotechnical testing
  • β€’Horizontal drains reduced pore pressure by 65% within 6 months
  • β€’Toe buttressing provided immediate kinematic restraint

βœ… Key Takeaways

  • 1Hydrogeological mapping is as critical as geotechnical testing
  • 2Horizontal drains reduced pore pressure by 65% within 6 months
  • 3Toe buttressing provided immediate kinematic restraint