Determination of Mechanical Properties for Cement- …

1 Determination of Mechanical Properties for Cement- Treated Aggregate Base M. SHABBIR HOSSAIN, , Senior Research Scientist HARIKRISHNAN NAIR, , Research Scientist H. CELIK OZYILDIRIM, , Principal Research Scientist Final Report VTRC 17-R21 Standard Title Page - Report on Federally Funded Project 1. Report No.: 2. Government Accession No.: 3. Recipient s Catalog No.: FHWA/VTRC 17-R21 4. Title and Subtitle: 5. Report Date: Determination of Mechanical Properties for Cement- Treated Aggregate Base June 2017 6.

2 Performing Organization Code: 7. Author(s): M. Shabbir Hossain, , , Harikrishnan Nair, , , and H. Celik Ozyildirim, , 8. Performing Organization Report No.: VTRC 17-R21 9. Performing Organization and Address: Virginia Transportation Research Council 530 Edgemont Road Charlottesville, VA 22903 10. Work Unit No. (TRAIS): 11. Contract or Grant No.: 104524 12. Sponsoring Agencies Name and Address: 13. Type of Report and Period Covered: Virginia Department of Transportation 1401 E. Broad Street Richmond, VA 23219 Federal Highway Administration 400 North 8th Street, Room 750 Richmond, VA 23219-4825 Final 14.

3 Sponsoring Agency Code: 15. Supplementary Notes: 16. Abstract: The Virginia Department of Transportation (VDOT) currently follows pavement design procedures for all new and rehabilitated pavements based on the 1993 AASHTO Guide for Design of Pavement Structures. VDOT s Materials Division is in the process of implementing the Mechanistic-Empirical Pavement Design Guide (MEPDG) procedure via AASHTOWare Pavement ME Design software. The MEPDG uses Mechanical Properties of pavement materials for pavement structural design.

4 The mechanistic-empirical design process presents a major change in pavement design from the 1993 AASHTO design guide. It calculates pavement responses through mechanistic analysis based on inputs such as traffic, climate, and materials Properties to predict the pavement damage or distress over time for both asphalt and concrete pavements. The purpose of this study was to evaluate the Mechanical Properties of Cement- treated aggregate (CTA) and recommend values for use in AASHTOWare Pavement ME Design software.

5 The field construction of CTA was monitored, and samples were collected for laboratory Determination of the compressive strength, modulus of elasticity, and modulus of rupture. Tests with the falling weight deflectometer were conducted to back-calculate the CTA modulus of elasticity, and field cores were collected for testing compressive strength and modulus of elasticity. CTA gained strength with increases in cement content, and the increase in strength and the strength level depended on the aggregate Properties , such as the resilient modulus of unbound aggregate.

6 All measured Properties were highly variable. VDOT would need to implement a strength-based CTA design to be able to use the required Mechanical Properties of CTA in the MEPDG system. The study recommends using a target design 7-day compressive strength of 600 to 800 psi. Such strength corresponds well with VDOT s current pavement design practice in accordance with the 1993 AASHTO design guide. CTA Mechanical Properties were suggested based on this target strength. Most of the default values presented in the MEPDG are considered reasonable.

7 In addition, the values recommended for use in the MEPDG are million psi for modulus of elasticity and 200 psi for modulus of rupture. 17 Key Words: 18. Distribution Statement: cement treated aggregate, CTA, MEPDG and stabilized base No restrictions. This document is available to the public through NTIS, Springfield, VA 22161. 19. Security Classif. (of this report): 20. Security Classif. (of this page): 21. No. of Pages: 22. Price: Unclassified Unclassified 52 Form DOT F (8-72) Reproduction of completed page authorized FINAL REPORT Determination OF Mechanical Properties FOR Cement- TREATED AGGREGATE BASE M.

8 Shabbir Hossain, , Senior Research Scientist Harikrishnan Nair, , Research Scientist H. Celik Ozyildirim, , Principal Research Scientist In Cooperation with the Department of Transportation Federal Highway Administration Virginia Transportation Research Council (A partnership of the Virginia Department of Transportation and the University of Virginia since 1948) Charlottesville, Virginia June 2017 VTRC 17-R21 ii DISCLAIMER The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the data presented herein.

9 The contents do not necessarily reflect the official views or policies of the Virginia Department of Transportation, the Commonwealth Transportation Board, or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. Any inclusion of manufacturer names, trade names, or trademarks is for identification purposes only and is not to be considered an endorsement. Copyright 2017 by the Commonwealth of Virginia. All rights reserved. iii ABSTRACT The Virginia Department of Transportation (VDOT) currently follows pavement design procedures for all new and rehabilitated pavements based on the 1993 AASHTO Guide for Design of Pavement Structures.

10 VDOT s Materials Division is in the process of implementing the Mechanistic-Empirical Pavement Design Guide (MEPDG) procedure via AASHTOWare Pavement ME Design software. The MEPDG uses Mechanical Properties of pavement materials for pavement structural design. The mechanistic-empirical design process presents a major change in pavement design from the 1993 AASHTO design guide. It calculates pavement responses through mechanistic analysis based on inputs such as traffic, climate, and materials Properties to predict the pavement damage or distress over time for both asphalt and concrete pavements.