{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Instability Rutting

# Instability Rutting - Proposed Failure Mechanism for...

This preview shows pages 1–9. Sign up to view the full content.

Proposed Failure Mechanism for Instability Rutting in Asphalt Pavements Reebie Simms

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
3-D Tire-Pavement Model Developed a 3-D FEM model of a radial dual truck and typical pavement system Stress states under the tire loading in the middle transverse plane of interest Investigated instability rutting using induced stress states
Investigation of Slip Planes Using the 3D Tire- Pavement Contact Model examine multiple depths within the AC layer Can we identify a mechanism that causes instability rutting ? Is there a critical depth(s)?

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Yield Ratio Use the concept of yield ratio (YR) to determine the degree of criticality of each stress state Mohr-Coulomb criterion assumes the material will fail or yield if q is equal to q f (in p-q space) or the YR is equal to 1 k-line: q f = a + p tan( )
Yield Ratio (cont.) C:30 psi ;Ф: 20º YR for multiple depths along middle vertical plane 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 -10 -8 -6 -4 -2 0 2 4 6 8 10 YR Tire Lateral Location (in.) Yield-Ratio 1in 2in 2.8in 4in No sense of direction – direction important in shear flow! No sense of continuity to form slip planes

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Maximum Shear Each element has an equal and opposite max. shear stress Always choose positive max. shear to ensure continuity of the potential slip plane causing the material to flow to the right Action Reaction
Maximum Shear (cont.) Superimpose max. shear contour with max. shear vectors Both magnitude and direction important 0 2 4 6 8 10 12 -4 -3 -2 -1 0

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Maximum Shear (cont.) Choose potential slip planes Plane No.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 25

Instability Rutting - Proposed Failure Mechanism for...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online