wuttichai prachantrikal master candidate geotechnical engineering civil and environmental...

Wuttichai PrachantrikalMaster Candidate

Geotechnical Engineering

Civil and Environmental EngineeringUniversity of Missouri - Columbia

Hydraulic Conductivity of MoDOT Type 5 Base Rock


• Background

• Objective

• Scope of Work

• Methodology

• Results to Date

• Ongoing Activities


Type 5 Base Rock is a material containing a wide particle size distribution of gravel, sand, and fines.

Used for the base of roadways.


Type 5 Base on Roadway

~4 inches


Hydraulic conductivity of the base for good drainage practice should be about 1 cm/s

“The conventional undrained pavements which fail prematurely from water damage are extremely uneconomical in the long-run when compared with well drained pavement”

Life undrain pavement ~ 15-30 yrsLife well drain pavement ~ 45-90 yrs

(H.R.Cedergren, 1967)



Rigid Surface

Base

Subbase

Infiltration

No drainage

Objective:

Determine the hydraulic conductivity of MoDOT Type 5 base rock and the impact of fines content on the hydraulic conductivity


Scope of work:

1. For a single Type 5 source: a. grain size distribution b. compaction curve c. hydraulic conductivity ( of the

compaction curve)

2. Effects of fines content:a. compaction curveb. hydraulic conductivityc. long term flow


Methodology:

1. Sieving

2. Compaction

3. Permeability Testing


Sieving:


Type 5 Grain Size Distribution MoDOT Spec.

0

10

20

30

40

50

60

70

80

90

100

0.010.1110100

opening (mm)

%fi

ner

MoDOT Lower Bound

MODOT Upper Bound

Percent Fine Range from 0 to 15 percent

Sieving:


Aggregate Used in Test

• Boone Quarries, Columbia, Missouri• Fines (Passing #200) – Sieved out• Re-Blend the Aggregate to Percent Fine @ 0, 3, 6, 9, 12, 15%


Compaction

• ASTM D698 Standard Proctor• 6” Diameter 4.5” Height Mold• 56 Blows per lift – 3 lifts


Compaction

Proctor Curve

120

122

124

126

128

130

132

134

2 4 6 8 10 12 14 16

water content %

Dry

un

it w

eig

ht

(pc

f)


max

wopt

Permeability Testing

Rigid-wall, Double-Ring:


Constraints:

1. 4” diameter mold

2. Side wall leakage

3. 1/8” diameter port

4. Sr < 1

Rigid-wall, Double-Ring:

6-inch constant head test:


6” mold

6-inch constant head test:

Advantages:1. 6” diameter2. Saturated Sr=13. Large Flow Capacity

6” mold


29.25 in

4 in

4 in

5 in

inflowoverflow

Type5

outflow

25.25”

4”

4”

5”

4-inch long-term flow test:

GT


Result to Date:

1. Grain Size Dist. Boone County Quarries


Unmodified

0

10

20

30

40

50

60

70

80

90

100

0.010.1110100

opening (mm)

%fi

ner

MoDOT Low er Bound

MODOT Upper Bound

Boone County Aggregate

Grain Size Dist. Boone County Quarries


0

20

40

60

80

100

0.010.1110100

opening (mm)

%fin

er

MoDOT Low er Bound

MODOT Upper Bound

0% fine

0% Fine

2. Compaction Curve

Proctor Curve 4.5% Fines - 4 in mold

125127129131133135137139

2 4 6 8 10 12 14 16

water content (%)

Dry

uni

t wei

ght

(pcf

)


Proctor Curve 3% Fine - 6 in Mold

120.0122.0124.0126.0128.0130.0132.0134.0

4 6 8 10 12 14 16

water content %

Dry

un

it w

eig

ht

(pc

f)

Compaction Curve (cont’)


3. Hydraulic Conductivity – 4.5% Fine Rigid Wall Double Ring

1.0E-06

1.0E-05

1.0E-04

1.0E-03

2 4 6 8 10 12 14 16

water content (%)

k (

cm

/s)

k inner

Proctor Curve / Permeability 4.5% Fines 4 in mold

125127129131133135137139141

2 4 6 8 10 12 14 16

d (

pc

f)


y = 0.0093x

y = 0.0111x

0.0E+00

1.0E-02

2.0E-02

3.0E-02

4.0E-02

5.0E-02

6.0E-02

7.0E-02

0 1 2 3 4 5 6 7

i

q/A

(c

m/s

)

inner ring outer ringLinear (inner ring) Linear (outer ring)

k w/ soil (max) = 2 x10-4 cm/sk inner ring = 1.1x10-2 cm/s (k system)k outer ring = 9.3x10-3 cm/s (k system)k system > k w/soil OK


Rigid Wall Double Ring (Calibration)

Hydraulic Conductivity – 3%FineProctor Curve / Permeability

3% Fine 6 in mold

120122124126128130132134

4 6 8 10 12 14 16

d (p

cf)

1.0E-02

1.0E-01

4 6 8 10 12 14 16water content

k (c

m/s

)


% Fines d max (pcf) w% k (cm/s) k (ft/d)

0 130.6 10.5 6.1E-02 1.7E+023 133.1 9.5 3.5E-02 9.9E+016 135.5 10 2.0E-03 5.7E+00

Hydraulic Conductivity of Type 5 Base


Hazen (1911)k(cm/s) = D10

2

Moulton (1979)k(ft/d) = [ 6.214x105 D10

1.478 n6.654 ]/P2000.597

D10 = particle size in mm at 10% passingn = porosityP200 = percent passing No.200


Predicted k vs. Measured k


1.0E-03

1.0E-02

1.0E-01

1.0E+00

0 2 4 6 8Fine content (%)

k (

cm

/s)

Measure Hazen Moulton

Summary of Results


%Fines dmax (pcf) w% n k (cm/s) k Hazen (cm/s) k Moulton (cm/s)

0 130.6 10.5 0.295 6.1E-02 9.0E-02 4.4E-023 133.1 9.5 0.282 3.5E-02 3.2E-02 2.0E-036 135.5 10 0.269 2.0E-03 4.0E-02 1.1E-03

Long term flowFlow Rate vs. Time, Type 5 Base, Long Term Flow

0

5

10

15

20

25

0.1 1 10 100 1000

Elapsed Time (hr)

Flo

w (

L/s

ec

)x1

0-3

0% Fines 3% Fines 6% Fines 9% Fines 12% Fines 15% Fines


Observation to Date


• Percent fines in unmodified Type 5 base ~ 4-5%• 4 in Rigid Wall Double Ring give much lower k than 6 in permeameter • Max Dry Unit weight increase with fine content• k decrease with fines content• k measure is close to k hazen at both 0, 3% but higher at 6% fines• k measure is close to k moulton at 6% but lower at 3% fines• Flow rate decrease with time in Long term flow and get to the steady state at about 50 hrs


On Going Activities

• Continue on 6,9,12,15 Percent Fine• Long term flow (Awilda) • Field k

Question?



0

10

20

30

40

50

60

70

80

90

100

0.010.1110100

opening (mm)

%fi

ne

r

MoDOT Lower Bound

3% fine

MoDOT Upper Bound

3% Fine



6% Fine

0

10

20

30

40

50

60

70

80

90

100

0.010.1110100

opening (mm)

%fi

ne

r

MoDOT Lower Bound

6% fine

MoDOT Upper Bound

Proctor Curve 0% Fine - 6 in Mold

120.0122.0124.0126.0128.0130.0132.0134.0

2 4 6 8 10 12 14 16

water content %

Dry

un

it w

eig

ht

(pc

f)



Proctor Curve - 6% Fine

124.0126.0128.0130.0132.0134.0136.0138.0

4 6 8 10 12 14 16

water content %

Dry

un

it w

eig

ht

(pcf

)



1.0E-02

1.0E-01

4 6 8 10 12 14 16

water content

k (c

m/s

)

Proctor Curve / Permeability 0% Fine 6 in mold

120122124126128130132134

4 6 8 10 12 14 16

d (

pcf

)

Hydraulic Conductivity - 0% Fine


Hydraulic Conductivity – 6%Fine


1.0E-03

1.0E-02

1.0E-01

4 6 8 10 12 14 16

water content

k (c

m/s

)

Proctor Curve / Permeability 6% Fine 6 in mold

124126128130132134136138

4 6 8 10 12 14 16

d (p

cf)

wuttichai prachantrikal master candidate geotechnical engineering civil and environmental...

Documents

base of roadways

grain size distribution

missouri fines

wpan wjws

hydraulic conductivityc

impact of fines content

percent fine range

effects of fines content