📋 Case Study
Post-Earthquake Landslide Stabilization — Kaikōura, New Zealand
Multiple deep-seated rockslides blocking critical transport corridor; unstable toe conditions and high pore pressures
🏗️ Project Overview
Rehabilitation of State Highway 1 after 2016 M7.8 earthquake
🎯 Challenge
Multiple deep-seated rockslides blocking critical transport corridor; unstable toe conditions and high pore pressures
🔧 Design Approach
Combined approach: deep drainage tunnels + soil-nailed upper slope + dynamic compaction at toe + real-time inclinometer/piezo monitoring network
📐 Design Diagram
AI-generated project design illustration
📐 Key Calculations
Bishop FoS (pre-remediation)
Σ(c·l + (W·cosα − u·l)·tanφ) / Σ(W·sinα)
Result: 1.08
Below minimum 1.3 for permanent highway cut
Drainage Tunnel Flow Capacity
Q = k·i·A
Result: 12.4 L/s
Designed to intercept >90% of infiltration flux
Soil Nail Load Distribution
T_max = γ·H²·K_a·cosβ / 2
Result: 185 kN/nail
Governed nail spacing and bond length design
📊 Results
Highway reopened in 11 weeks; zero post-construction movement over 3-year monitoring; 22% under budget💡 Lessons Learned
- •Real-time pore pressure feedback enabled adaptive dewatering sequencing
- •Soil nailing performed best where rock mass quality was RMR > 50
- •Pre-excavation grouting reduced nail installation torque variability by 37%
✅ Key Takeaways
- 1Real-time pore pressure feedback enabled adaptive dewatering sequencing
- 2Soil nailing performed best where rock mass quality was RMR > 50
- 3Pre-excavation grouting reduced nail installation torque variability by 37%