FORMULATION OF MIX DESIGN TO INCORPORATE HYDROCARBON AFFECTED SOIL IN ASPHALT STABILIZED BASE

1. FORMULATION OF MIX DESIGN TO INCORPORATE HYDROCARBON AFFECTED SOIL IN ASPHALT STABILIZED BASE Prepared by: Michael Ruckgaber Summer 2000 REU

2. Aknowledgements • Dr. Musharraf Zaman • Rafiqul Tarefder • Don Steel • Cheong Fong

3. Introduction • 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)

4. Benefits • Energy savings • Cold-Mix Asphalt (CMA) using emulsion is less polluting than Hot-Mix Asphalt (HMA) • Extremely versatile – long-term use • Recyclable

5. Objectives • 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

6. Soil Analysis Moisture content, sieve analysis, specific gravity, hydrometer test, liquid limit, plastic limit, plasticity index, sand equivalent test, and finally, soil classification Aggregate Analysis (Don Steel) Moisture content, sieve analysis, LA abrasion, sand equivalent test, fractured faces, and specific gravity Research Plan

7. Mix Design Emulsion Type, Emulsion Content by Equation, Coating and Adhesion Tests, Optimum Emulsion and Moisture Contents, and Additives Sample Preparation and Evaluation Mixing, Curing, Resistance by Hveem Stability Method, Split-Tensile Strength Research Plan, cont.

8. Moisture content – 13.4% Average of 43% material by weight passed No. 200 sieve Soil Classification AASHTO – A-4(0) and A-4(2) USDA – Sandy loam and sandy clay loam Unified Soil – Sandy organic clay (OL) Soil Analysis

9. 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), Aggregate Analysis

10. 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% Mix Design

11. Sample Preparation Overview • 85 total samples • 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

12. Sample Preparation Cont. • 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 • Early – 24 hours at around 778F • Vacuum – early cured, then submerged in vacuum for 1 hour, and submerged for 1 more hour

13. Mold for Compactor

14. Texas Gyratory Compactor

15. Asphalt Samples

16. MTS Compression Machine

17. Sample Preparation, Cont. • Resistance values – must be above requirement of 70 • Split-tensile values – must be above 35 psi (TxDOT compressive requirement)

18. Conclusions • Soil – passed all requirements • Soil is very light (specific gravity less than 2) • Cement helps to increase the size of particles • Aggregate – passed all requirements • 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

19. Conclusions, Cont. • 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

20. Recommendations • 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