Transcript FORMULATION of MIX DESIGN TO INCORPORATE …

FORMULATION OF MIX DESIGN TO
INCORPORATE HYDROCARBON
AFFECTED SOIL IN ASPHALT
STABILIZED BASE
Prepared by:
Michael Ruckgaber
Summer 2000 REU
Aknowledgements
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Dr. Musharraf Zaman
Rafiqul Tarefder
Don Steel
Cheong Fong
Introduction
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Heavy-chain hydrocarbon and metal
affected soil from Kerr-McGee Cleveland
site
Possible actions – ignorance, placement in
landfill, biodegradation, soil washing
Preferred action – stabilization with asphalt
emulsion and incorporation into Asphalt
Stabilized Base (ASB)
Benefits
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Energy savings
Cold-Mix Asphalt (CMA) using emulsion
is less polluting than Hot-Mix Asphalt
(HMA)
Extremely versatile – long-term use
Recyclable
Objectives
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Incorporate the maximum amount of soil
into suitable mix design
Find the optimum amount of emulsion,
moisture, and cement to add
Ensure that the mix will surpass strength,
resistance, and sensitivity to moisture
damage requirements
Research Plan
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Soil Analysis
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Moisture content,
sieve analysis,
specific gravity,
hydrometer test,
liquid limit, plastic
limit, plasticity
index, sand
equivalent test, and
finally, soil
classification
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Aggregate Analysis
(Don Steel)
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Moisture content,
sieve analysis, LA
abrasion, sand
equivalent test,
fractured faces, and
specific gravity
Research Plan, cont.
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Mix Design
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Emulsion Type, Emulsion Content by Equation,
Coating and Adhesion Tests, Optimum Emulsion
and Moisture Contents, and Additives
Sample Preparation and Evaluation
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Mixing, Curing, Resistance by Hveem Stability
Method, Split-Tensile Strength
Soil Analysis
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Moisture content –
13.4%
Average of 43%
material by weight
passed No. 200 sieve
Soil Classification
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AASHTO – A-4(0)
and A-4(2)
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USDA – Sandy loam
and sandy clay loam
Unified Soil – Sandy
organic clay (OL)
Aggregate Analysis
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Preformed by Don Steel, student here
Surpassed all set requirements by Oklahoma
Department of Transportation (ODOT) and Texas
Department of Transportation (TxDOT), like
gradation, fractured Faces (75% with 2), and
Sand Equivalent (minimum of 40),
Mix Design
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Emulsion type – CSS-1h
Coating, more than 50%) and adhesion tests
(boiling water)
Optimum emulsion content – 4.5
Additives – Cement at 0, 1 and 2%
Sample Preparation Overview
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85 total samples
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34 50% soil, 50% aggregate (50/50)
21 60/40
12 70/30
6 80/20
Most with 2% cement
Some early cured, some fully cured
Sample Preparation Cont.
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1/3 water, mix, cement (if any), mix, 1/3 water,
mix, 1/3 water, mix, emulsion, mix, mechanical
mixer
Compacted using a Rainhart Gyratory Compactor
Curing
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Early – 24 hours at around 778F
Vacuum – early cured, then submerged in vacuum for
1 hour, and submerged for 1 more hour
Mold for Compactor
Texas Gyratory Compactor
Asphalt Samples
MTS Compression Machine
Sample Preparation, Cont.
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Resistance values – must be above
requirement of 70
Split-tensile values – must be above 35 psi
(TxDOT compressive requirement)
Conclusions
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Soil – passed all requirements
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Aggregate – passed all requirements
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Soil is very light (specific gravity less than 2)
Cement helps to increase the size of particles
Very coarse, well suited for mixing with soil
The 80% soil 20% aggregate mix provided
adequate resistance and tensile strength values
Would have tried 100% soil, but ran out of time –
will more than likely work
Conclusions, Cont.
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More emulsion is need with mixtures
containing high percentages of soil
Cement is also needed with high soil
percentages
Using more soil in a mix is cheaper, but
requires more emulsion and cement
Recommendations
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This process will stabilized the affected soil
in a productive, economic, viable product
that saves the tax payer’s money
Investigation of other additives such as
lime, fly ash, and cement kiln dust (CKD)
could be useful
Could also investigate asphalt
incorporation using HMA design