co-pis: erol tutumluer marshall r. thompson ra: h.s. brar subgrade soil support and stabilization...
TRANSCRIPT
Co-PIs:Co-PIs: Erol Tutumluer Erol Tutumluer Marshall R. ThompsonMarshall R. Thompson
RA:RA: H.S. BrarH.S. Brar
Subgrade Soil Support Subgrade Soil Support and Stabilizationand Stabilization
O’HARE Airport Modernization Research ProjectO’HARE Airport Modernization Research Project
Introduction
Subgrade performanceSubgrade performance is a key factor in the overall is a key factor in the overall pavement performancepavement performance
National AirportNational AirportPavement Test Pavement Test Facility - Facility - Atlantic City, NJAtlantic City, NJ
This project provides This project provides testing and analysistesting and analysis to establish to establish subgrade support and stabilization requirementssubgrade support and stabilization requirements for O’Hare airport pavementsfor O’Hare airport pavements
P154
P209
Introduction (cont’d)
The preliminary concrete pavement design for the The preliminary concrete pavement design for the O’Hare Modernization Program (OMP)O’Hare Modernization Program (OMP)::
• 15 – 17 inches of PCC Surface15 – 17 inches of PCC Surface• 6-inch Hot Mix Asphalt Base6-inch Hot Mix Asphalt Base• 6-inch Asphalt Treated Permeable Base (!?) 6-inch Asphalt Treated Permeable Base (!?) • ““Stabilized” Subgrade Zone (SSZ)Stabilized” Subgrade Zone (SSZ)• Prepared SubgradePrepared Subgrade
North Runway (9L-27R, 7,500 ft)North Runway (9L-27R, 7,500 ft) paving is scheduled paving is scheduled first for the Spring 2006 (!?)first for the Spring 2006 (!?)
• Stockpiles of local soil on runway centerline (excavated Stockpiles of local soil on runway centerline (excavated from the “Deep Pond” nearby)from the “Deep Pond” nearby)
• Primarily fill and cut areasPrimarily fill and cut areas
Research Objectives
Consider pavement design inputs for subgrade Consider pavement design inputs for subgrade supportsupport
• Modulus of subgrade reaction, kModulus of subgrade reaction, k
Consider subgrade support and stabilization Consider subgrade support and stabilization requirements with respect to:requirements with respect to:
• Need for subgrade stabilizationNeed for subgrade stabilization• Stabilization admixture(s) stabilizationStabilization admixture(s) stabilization• Stabilization depthStabilization depth
Estimate “Estimate “subgrade supportsubgrade support” for various ” for various combinations of subgrade stabilization treatments combinations of subgrade stabilization treatments and prepared subgrade conditionsand prepared subgrade conditions
Project Tasks
Task 1:Task 1:
Establish the Best Demonstrated Available Establish the Best Demonstrated Available Technology (BDAT) for subgrade soil evaluation Technology (BDAT) for subgrade soil evaluation and stabilization and stabilization (Ongoing)(Ongoing)
Reports and publications collected & submitted as Reports and publications collected & submitted as “Technical Notes” on:“Technical Notes” on:
• Subgrade strength/stiffness evaluation techniquesSubgrade strength/stiffness evaluation techniques• Subgrade stability requirements & IDOT ManualSubgrade stability requirements & IDOT Manual• ““Working platform” requirements for pavement Working platform” requirements for pavement
constructionconstruction
Project Tasks
Task 2:Task 2:
Evaluate currently available data for the subgrade test Evaluate currently available data for the subgrade test sections constructed in the Fall of 2003 and the sections constructed in the Fall of 2003 and the necessity/usefulness of constructing additional necessity/usefulness of constructing additional subgrade treatment test sections at O’Haresubgrade treatment test sections at O’Hare
(Effort completed)(Effort completed)
Plate load tests conducted (8/04) on the test sections:Plate load tests conducted (8/04) on the test sections:• Plate 1:Plate 1: 12-inch stabilization/compaction – no admixture 12-inch stabilization/compaction – no admixture• Plate 2:Plate 2: 12-inch quicklime fine (40 lb/yd 12-inch quicklime fine (40 lb/yd22) & fly ash (80 ) & fly ash (80
lb/ydlb/yd22) stabilization) stabilization
• Plate 3:Plate 3: 12-inch quicklime fine stabilization (40 lb/yd 12-inch quicklime fine stabilization (40 lb/yd22) ) • Plate 4:Plate 4: 12-inch lime kiln dust stabilization (40 lb/yd 12-inch lime kiln dust stabilization (40 lb/yd22))
Plate Load Tests Plate Load Tests
Modulus of Subgrade Modulus of Subgrade Reaction, kReaction, k
Project Tasks
Task 3:Task 3:
Advise OMP on current and future test section Advise OMP on current and future test section monitoring and field test evaluation programsmonitoring and field test evaluation programs
(Effort completed)(Effort completed)
Various field tests may be useful to characterize the Various field tests may be useful to characterize the treated subgrade (OMP will arrange for testing):treated subgrade (OMP will arrange for testing):
• Dynamic Cone Penetrometer (8/04)Dynamic Cone Penetrometer (8/04)• Light-Weight Deflectometer (8/04)Light-Weight Deflectometer (8/04)• Clegg Hammer Clegg Hammer • GeogaugeGeogauge• Heavy Weight Deflectometer (HWD)Heavy Weight Deflectometer (HWD)• Ground Penetrating Radar (GPR)Ground Penetrating Radar (GPR)• Seismic Pavement Analyzer, SASW, etc. Seismic Pavement Analyzer, SASW, etc.
Light-WeightLight-WeightDeflectometer Deflectometer
Dynamic ConeDynamic ConePenetrometerPenetrometer
Project Tasks
Task 4:Task 4:
Evaluate currently available geotechnical/subgrade Evaluate currently available geotechnical/subgrade data for the North Runway with emphasis on the data for the North Runway with emphasis on the stockpiled “Deep Pond” soils. Recommend further stockpiled “Deep Pond” soils. Recommend further soil sampling & testing to be conducted (by an OMP soil sampling & testing to be conducted (by an OMP designated testing firm) designated testing firm) (Ongoing)(Ongoing)
Routine tests to establish representative soils Routine tests to establish representative soils existing for the runway subgradeexisting for the runway subgrade
• Grain size distribution (including hydrometer)Grain size distribution (including hydrometer)• Atterberg limits (LL and PL for PI)Atterberg limits (LL and PL for PI)• Moisture-density-CBR Moisture-density-CBR • PH value & calcareous content PH value & calcareous content • If needed, organic matter contentIf needed, organic matter content
Preliminary Geotechnical Report
Soil sampling & testing conducted by Everest Soil sampling & testing conducted by Everest Engineering on OMP Runway 9L-27R - Engineering on OMP Runway 9L-27R - October 2004October 2004
Boring Boring LogsLogs
Atterberg limits Atterberg limits (LL and PL for PI)(LL and PL for PI)
Preliminary Geotechnical Report
Soil sampling & testing conducted by Everest Soil sampling & testing conducted by Everest Engineering on OMP Runway 9L-27R - Engineering on OMP Runway 9L-27R - October 2004October 2004
Grain size distribution Grain size distribution (including hydrometer)(including hydrometer)
Preliminary Geotechnical Report
Soil sampling & testing conducted by Everest Soil sampling & testing conducted by Everest Engineering on OMP Runway 9L-27R - Engineering on OMP Runway 9L-27R - October 2004October 2004
Moisture-density-CBR Moisture-density-CBR
Preliminary Geotechnical Report
Soil sampling & testing conducted by Everest Soil sampling & testing conducted by Everest Engineering on OMP Runway 9L-27R - Engineering on OMP Runway 9L-27R - October 2004October 2004
Unconfined Compressive Strength, Qu Unconfined Compressive Strength, Qu
Soil Sampling: Dec. 04 – Feb. 05
Current scheduled soil sampling & testing from the R9L-27RCurrent scheduled soil sampling & testing from the R9L-27R
The Drilling Program The Drilling Program • Auger borings, 17 boreholes, MT-1 to MT-17 Auger borings, 17 boreholes, MT-1 to MT-17 • 10’ to 45’ depths through fill & cut areas 10’ to 45’ depths through fill & cut areas • All reaching down to elev. 640’ in the natural subgradeAll reaching down to elev. 640’ in the natural subgrade• 3 North of runway, 3 North edge of runway, 4 under 3 North of runway, 3 North edge of runway, 4 under
runway, 2 South edge of runway, 2 between runway and runway, 2 South edge of runway, 2 between runway and taxiway, and 3 under taxiway taxiway, and 3 under taxiway
• SPT and soil sampling at 2.5’SPT and soil sampling at 2.5’• Moisture content, LL, PI, grain size distribution (%clay)Moisture content, LL, PI, grain size distribution (%clay)• Shelby tube samples at each location (638’ to 642’)Shelby tube samples at each location (638’ to 642’)• At least 1 bucket for each major soil in each boreholeAt least 1 bucket for each major soil in each borehole• Two 5-gallon buckets (60-70 lbs./bucket) for each Two 5-gallon buckets (60-70 lbs./bucket) for each
representative soil (composite sample) to test at the representative soil (composite sample) to test at the University of IllinoisUniversity of Illinois
Soil Sampling: Dec. 04 – Feb. 05
University of Illinois input/review – The Drilling ProgramUniversity of Illinois input/review – The Drilling Program
Laboratory Testing NeedsLaboratory Testing Needs• Check the pH of the soil samplesCheck the pH of the soil samples• Check the samples for “free carbonates” by squirting with Check the samples for “free carbonates” by squirting with
10% HCl solution 10% HCl solution • How are the SPT samples handled?How are the SPT samples handled?
““N” counts will be helpful in assessing the mobility N” counts will be helpful in assessing the mobility characteristics (sinkage/rolling resistance) of the characteristics (sinkage/rolling resistance) of the stockpiled soilsstockpiled soils
• What tests are conducted with the Shelby tube samples?What tests are conducted with the Shelby tube samples?
Undisturbed samples obtained from the natural Undisturbed samples obtained from the natural subgrade (finished subgrade elevation) will be best subgrade (finished subgrade elevation) will be best utilized to run unconfined compressive strength and utilized to run unconfined compressive strength and resilient modulus tests resilient modulus tests
Project Tasks
Task 5:Task 5:
Based on the data and information gathered in Task Based on the data and information gathered in Task 4, select (in consultation with OMP) the identified 4, select (in consultation with OMP) the identified representative soilsrepresentative soils and recommend an admixture and recommend an admixture stabilization program stabilization program (Ongoing)(Ongoing)
Tests to be conducted at the Tests to be conducted at the UIUC Advanced UIUC Advanced Transportation Research and Engineering Laboratory Transportation Research and Engineering Laboratory (ATREL)(ATREL) on both untreated & treated soilson both untreated & treated soils
• Moisture-Density-CBR Moisture-Density-CBR • Unconfined Compressive Strength Unconfined Compressive Strength • Resilient ModulusResilient Modulus• Permanent Deformation @ 6-psi deviator stressPermanent Deformation @ 6-psi deviator stress
Project Challenges
Proper sampling of the R9L-27R Proper sampling of the R9L-27R stockpiled soilsstockpiled soils
Selecting & identifying Selecting & identifying representative soil samplesrepresentative soil samples
Adequately characterizing the representative soil Adequately characterizing the representative soil samples by conductingsamples by conducting tests at the UIUC ATREL for tests at the UIUC ATREL for
• Moisture-Density-CBR Moisture-Density-CBR • Unconfined Compressive Strength Unconfined Compressive Strength • Resilient Modulus Resilient Modulus
• Permanent Deformation @ 6-psi deviator stress Permanent Deformation @ 6-psi deviator stress
University of Illinois Laboratory Testing Program at ATREL
Advanced Transportation Research & Engineering Laboratory (ATREL)Advanced Transportation Research & Engineering Laboratory (ATREL)
Admixture Types / Sources
Carmeuse (potential supplier)Carmeuse (potential supplier)South Chicago (dolomitic lime)South Chicago (dolomitic lime)Buffington, IN (high calcium lime)Buffington, IN (high calcium lime)
Lime typesLime typesLime Kiln Dust (LKD)Lime Kiln Dust (LKD)Quicklime finesQuicklime fines
Buffington is the primary sourceBuffington is the primary source
(We will work with this & confirm with S. Chicago)(We will work with this & confirm with S. Chicago)
Moisture-
Density-
CBRCBRCBR
(ASTM D1883)(ASTM D1883)
Proctor Proctor Compaction Compaction
(ASTM D698, (ASTM D698, D1557)D1557)
UntreatedUntreated
Moisture-Density-CBR
Lime treatedLime treated
Lime treatedLime treated
Moisture-Density-CBR
TreatedTreated
LKD: Lime Kiln DustLKD: Lime Kiln Dust
Unconfined Compressive Strength
C C = (= (1f1f)/2 )/2
== Q Quu/2/2
11 1f1f3 3 = 0= 0
dd = = 11 – – 33(=0)(=0)
failurefailure
Cohesive Soils (c, Cohesive Soils (c, =0) =0)
(ASTM D2166)(ASTM D2166)
0
10
20
30
40
50
60
0 5 10 15Axial Strain, %
Ax
ial S
tre
ss, p
si
MC = 28.5 % DD = 93.5 pcfCBR = 4
MC = 23 % DD = 103.5 pcfCBR = 14
MC = 26 % DD = 98 pcfCBR = 8
MC = 30.5 % DD = 92.5 pcfCBR = 2.5
Dupont Clay
Typical Unconfined - Data
QQuu = unconfined = unconfined
compressive compressive strengthstrength
= peak = peak 11
Deviator Stress at Failure
Effect of CuringEffect of Curing
Deviator Stress at Failure
Resilient Modulus Testing
MMRR = resilient modulus = resilient modulus
= = dd / / rr
d d : Deviator stress: Deviator stress
rr : recoverable strain : recoverable strain
Conditioning:Conditioning: 200200 load applications at load applications at 33 = 0, = 0, dd = 41 kPa = 41 kPa
Testing:Testing: 100100 load applications load applications dd = 14, 28, 41, 55, 69, 83, 96, 110 kPa = 14, 28, 41, 55, 69, 83, 96, 110 kPa
dd
Unconfined: Unconfined: 3 3 = 0= 0
2-in. in 2-in. in
MR Tests – Soil Samples
Cylindrical specimens, 2 in. Cylindrical specimens, 2 in. by 4 in. high by 4 in. high
Undisturbed soil samplesUndisturbed soil samples – Shelby tube ( – Shelby tube (= 2.8, 4 in.)= 2.8, 4 in.)
0
4
8
12
16
20
24
28
0 2 4 6 8 10 12 14 16 18
APPLIED DEVIATOR STRESS d (psi)
RE
SIL
IEN
T M
OD
UL
US
MR (
ksi) A-4 soil at OMC A-4 soil at OMC
A-4 soil at OMC+3A-4 soil at OMC+3
MR = - 2.21248 d + 29.696
R2 = 0.9497
M R = - 0.6274d + 1820
R2 = 0.6617
M R = - 0.4203 d + 8.351
R2 = 0.8715MR = 0.0408 d + 4.9412
R2 = 0.8796
Typical MR Characterization
Bilinear or Bilinear or Arithmetic Arithmetic ModelModel
Greensboro, NC Airport Greensboro, NC Airport Subgrade SoilsSubgrade Soils
Resilient Modulus Testing
Resilient Modulus Testing
Resilient Modulus Testing
Project Deliverables
Technical NotesTechnical Notes have been / will be prepared and submitted to have been / will be prepared and submitted to the OMP throughout the project duration to communicate specific the OMP throughout the project duration to communicate specific findings and recommendations to OMP engineersfindings and recommendations to OMP engineers
Several of the Several of the Project TasksProject Tasks are being pursued simultaneously, are being pursued simultaneously, and the specific delivery of results will be contingent upon and the specific delivery of results will be contingent upon availability of OMP data and other factors that depend on availability of OMP data and other factors that depend on coordination with OMPcoordination with OMP
A A ReportReport summarizing the laboratory program will be prepared summarizing the laboratory program will be prepared
A A Final ReportFinal Report will be prepared at the end of the one-year study will be prepared at the end of the one-year study (September/October 2005)(September/October 2005)
We will We will continue to work with OMPcontinue to work with OMP on future subgrade soil on future subgrade soil support and stabilization needs for other runways/taxiwayssupport and stabilization needs for other runways/taxiways
Illini Apparently Have Spent A Little Longer At No. 1 This Time!..
GOGO ILLINI !..ILLINI !..