1. Failure Phenomenon Simulation by MPS-DEM Geotechnical Structure Elastic behavior: MPS Failure: DEM

2. Strength Parameters Tensile Strength for failure Maximum Shear Strength (not failure) 2 ctct c ij Shear Stress Normal Stress TensileCompression Initial 1 st parameter  ij ctct c ij New contact 2 nd parameter Coh_l ij

3. Compression Test Homogenous Compressive Condition Step-2 Compression 1: constant x-stress 2: constant y-stress 3: enforced y-displacement, x-fix 4: x,y fix Step-1 Confining Stress 1: x-stress, 2: x-stress 3: y-stress, 4: y-fix Confining Stress 25 kN/m 2 4 3 12 10m 20m 4 3 12 x y 3

4. Compression Test Type-2 formulation 4 Number of disconnected particles 0, 1, 2, 3, 4 more than 5 magnification ratio 5.0 Failed particles appear on conjugate 45 degree line regularly Nonlinearity can not be observed in strain-stress relation, etc., It is known that the regular gird (lattice) alignment affect the failure behavior JUMP Macro Strain and Stress Strain=disp. at top/length Stress=force at top/wedth

5. Compression Test Random Model 1 Seed of random number 111113 5 Number of disconnected particle 0, 1, 2, more than 3 magnification ratio 5.0 Jump

6. 6 Number of disconnected particle 0, 1, 2, more than 3 Seed of random number 111112 6 Compression Test Random Model 2 magnification ratio 5.0

7. Compression Test Comparison of lattice model and random model 7

8. Output Memo 8 Case 1 Big Model Confining Pressure=50 1.5-3.0 seconds Interaction condition Interaction Blue :initial, orange:weak Red: Dem, green:mps 2.0 秒間では ev2 がメモリ不 足 Uper, lower layer=0.4m, Seed of random number=1111112 Acceleration (H) Deviatonic Stress Axial Strain