wuttichai prachantrikal master candidate geotechnical engineering civil and environmental...
TRANSCRIPT
Wuttichai PrachantrikalMaster Candidate
Geotechnical Engineering
Civil and Environmental EngineeringUniversity of Missouri - Columbia
Hydraulic Conductivity of MoDOT Type 5 Base Rock
Geotechnical Engineering
• Background
• Objective
• Scope of Work
• Methodology
• Results to Date
• Ongoing Activities
Geotechnical Engineering
Type 5 Base Rock is a material containing a wide particle size distribution of gravel, sand, and fines.
Used for the base of roadways.
Geotechnical Engineering
Type 5 Base on Roadway
~4 inches
Geotechnical Engineering
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)
Geotechnical Engineering
Geotechnical Engineering
Rigid Surface
Base
Subbase
Infiltration
No drainage
Geotechnical Engineering
Objective:
Determine the hydraulic conductivity of MoDOT Type 5 base rock and the impact of fines content on the hydraulic conductivity
Geotechnical Engineering
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
Geotechnical Engineering
Methodology:
1. Sieving
2. Compaction
3. Permeability Testing
Geotechnical Engineering
Sieving:
Geotechnical Engineering
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:
Geotechnical Engineering
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%
Geotechnical Engineering
Compaction
• ASTM D698 Standard Proctor• 6” Diameter 4.5” Height Mold• 56 Blows per lift – 3 lifts
Geotechnical Engineering
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)
Geotechnical Engineering
max
wopt
Permeability Testing
Rigid-wall, Double-Ring:
Geotechnical Engineering
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:
Geotechnical Engineering
6” mold
6-inch constant head test:
Advantages:1. 6” diameter2. Saturated Sr=13. Large Flow Capacity
6” mold
Geotechnical Engineering
29.25 in
4 in
4 in
5 in
inflowoverflow
Type5
outflow
25.25”
4”
4”
5”
4-inch long-term flow test:
GT
Geotechnical Engineering
Result to Date:
1. Grain Size Dist. Boone County Quarries
Geotechnical Engineering
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
Geotechnical Engineering
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
)
Geotechnical Engineering
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’)
Geotechnical Engineering
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)
Geotechnical Engineering
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
Geotechnical Engineering
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
)
Geotechnical Engineering
% 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
Geotechnical Engineering
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
Geotechnical Engineering
Predicted k vs. Measured k
Geotechnical Engineering
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
Geotechnical Engineering
%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
Geotechnical Engineering
Observation to Date
Geotechnical Engineering
• 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
Geotechnical Engineering
On Going Activities
• Continue on 6,9,12,15 Percent Fine• Long term flow (Awilda) • Field k
Question?
Grain Size Dist. Boone County Quarries
Geotechnical Engineering
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
Grain Size Dist. Boone County Quarries
Geotechnical Engineering
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)
Geotechnical Engineering
Compaction Curve (cont’)
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
)
Compaction Curve (cont’)
Geotechnical Engineering
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
Geotechnical Engineering
Hydraulic Conductivity – 6%Fine
Geotechnical Engineering
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)