1. Task 4: DEM Modeling of Soil-Pile System Status Report Claudia Medina Mourad Zeghal RPI, February 15, 2005

2. Objective DEM modeling of soil-pile system – Coupled Soil-Pile model – Flexible (Elastic) Pile

3. Soil-Pile System

4. Soil-Pile Model Soil: Discrete Element Method (DEM) Pile: FEM (Bernoulli-Euler beam theory) Algorithm: DEM for particles Displacement for particles Force acting on the pile Forces acting on particles Displacement for pile FEM for pile

5. Bernoulli-Euler beam theory Beam finite elements – 2 end nodes and 4 DOF – Neglects transverse shear deformations

6. Element Equation

7. Global Equation [KG] =[KG] = K1K1 K2K2 K3K3 KnKn Assembly procedure for the beam with n elements

8. DEM model for a 10 element beam node 4 {u 4,  4 } node 5 {u 5,  5 } Element E5 q5q5 E1 E2 E3 E4 E5 E6 E7 E8 E9 E10 0 1 2 3 4 5 6 7 8 9 10

9. Model Properties DEM modelPrototype g-level50g1g Pile Radius, R3 mm15 cm Length, L5 cm2.5 m Young’s modulus, E200 GPa Moment of inertia, I0.0636 mm 4 39.76 cm 4 No elements10 Deposit Slope5 (deg) Particle radius, r1 mm

10. DEM Simulation t = 0

11. DEM Simulation t = 0.05 sec

12. DEM Simulation t = 0.10 sec

13. DEM Simulation t = 0.15 sec

14. DEM Simulation t = 0.20 sec

15. DEM Simulation t = 0.25 sec

16. DEM Simulation t = 0.30 sec

17. DEM Simulation t = 0.35 sec

18. DEM Simulation t = 0.40 sec

19. DEM Simulation t = 0.45 sec

20. DEM Simulation t = 0.50 sec

21. Pile displacement

23. Thank you