SLIDE 1
2
Resilient Modulus
Axial strain Deviator stress MR
Resilient Modulus Unbound Materials 1 Resilient Modulus M R - - PDF document
Resilient Modulus Unbound Materials 1 Resilient Modulus M R - - PDF document
Resilient Modulus Unbound Materials 1 Resilient Modulus M R Deviator stress Axial strain Resilient Modulus Cyclic Triaxial Test 2 Haversine Load Pulse Haversine Load Pulse sin t ( ) = 2 t T
SLIDE 2
SLIDE 3
3
Haversine Load Pulse Haversine Load Pulse
( )
2
sin ⎛ ⎞ σ = π ⎜ ⎟ ⎝ ⎠ t t T
Flowchart
SLIDE 4
4
Flowchart Flowchart
b
Procedure Ia
Sequence Confining Pressure (psi) Contact Stress (psi) Cyclic Stress (psi) Number
- f
Repetitions 15 3 30 1000 1 3 0.6 1.5 100 2 6 1.2 3 100 3 10 2 5 100 4 15 3 7.5 100 5 20 4 10 100 6 3 0.6 3 100 7 6 1.2 6 100 8 10 2 10 100 9 15 3 15 100 10 20 4 20 100 11 3 0.6 6 100 12 6 1.2 12 100 13 10 2 20 100 14 15 3 30 100 15 20 4 40 100
SLIDE 5
5
Procedure Ia (cont.)
Sequence Confining Pressure (psi) Contact Stress (psi) Cyclic Stress (psi) Number
- f
Repetitions 16 3 0.6 9 100 17 6 1.2 18 100 18 10 2 30 100 19 15 3 45 100 20 20 4 60 100 21 3 0.6 15 100 22 6 1.2 30 100 23 10 2 50 100 24 15 3 75 100 25 20 4 100 100 26 3 0.6 21 100 27 6 1.2 42 100 28 10 2 70 100 29 15 3 105 100 30 20 4 140 100
Procedure Ib
Sequence Confining Pressure (psi) Contact Stress (psi) Cyclic Stress (psi) Number
- f
Repetitions 4 0.8 8 1000 1 2 0.4 1 100 2 4 0.8 2 100 3 6 1.2 3 100 4 8 1.6 4 100 5 12 2.4 6 100 6 2 0.4 2 100 7 4 0.8 4 100 8 6 1.2 6 100 9 8 1.6 8 100 10 12 2.4 12 100 11 2 0.4 4 100 12 4 0.8 8 100 13 6 1.2 12 100 14 8 1.6 16 100 15 12 2.4 24 100 16 2 0.4 6 100 17 4 0.8 12 100 18 6 1.2 18 100 19 8 1.6 24 100 20 12 2.4 36 100
Procedure II
Sequence Confining Pressure (psi) Contact Stress (psi) Cyclic Stress (psi) Number
- f
Repetitions 4 0.8 7 1000 1 8 1.6 4 100 2 6 1.2 4 100 3 4 0.8 4 100 4 2 0.4 4 100 5 8 1.6 7 100 6 6 1.2 7 100 7 4 0.8 7 100 8 2 0.4 7 100 9 8 1.6 10 100 10 6 1.2 10 100 11 4 0.8 10 100 12 2 0.4 10 100 13 8 1.6 14 100 14 6 1.2 14 100 15 4 0.8 14 100 16 2 0.4 14 100
SLIDE 6
6
Granular Materials
Source: WSDOT Pavement Guide Interactive CD-ROM 2
1
= θK
R
M K
Fine-Grained Soils
Source: WSDOT Pavement Guide Interactive CD-ROM 4
3
= σ K
R d
M K
Uzan Model
6 7
5
= θ σ
K K R d
M K
SLIDE 7
7
Estimating Subgrade MR
1500 = ×
R
M CBR
WARNING: Only for fine-grained soils with soaked CBR < 10.
1993 AASHTO Guide
Estimating Subgrade MR
0.64
2555 = ×
R
M CBR
Good for a wide range of soil types
AASHTO MEPDG
MR vs. CBR
3000 6000 9000 12000 15000 1 2 3 4 5 6 7 8 9 10 CBR MR (psi) MR = 1500 CBR MR = 2555 CBR0.64
SLIDE 8
8
MR vs. CBR
10000 20000 30000 40000 50000 60000 70000 80000 5 10 15 20 25 30 35 40 45 50 CBR MR (psi) MR = 1500 CBR MR = 2555 CBR0.64
Correlations
1500 = ×
R
M CBR
Asphalt-Bound Materials
SLIDE 9
9
Diametral Resilient Modulus Calculation
4 1 ⎛ ⎞ = − + ν ⎜ ⎟ δ π ⎝ ⎠
R h
P M t
Calculation
( )
0.2734 = + ν δ
R h
P M t
SLIDE 10
10
Dynamic Modulus Complex Modulus Complex Dynamic Modulus
( )
*
cos sin σ = δ + δ ε
- E
i
SLIDE 11
11
Dynamic Modulus
( )
*
cos0 sin0 σ σ = + = ε ε
- E