Effect of Wet-Dry Cycles on Resilient Modulus of Class C Coal Fly Ash-Stabilized Aggregate Base

Abstract

A laboratory study was undertaken to investigate the effect of wet-dry (W-D) cycles on low-quality aggregates stabilized with Class C coal fly ash (CFA). Resilient modulus (M_r), unconfined compressive strength, and elastic modulus were used to evaluate this effect. Cylindrical specimens stabilized with 10% CFA, cured for 3 and 28 days, and subjected to different W-D cycles were tested. The M_r values of 28-day-cured specimens increased as W-D cycles increased up to 12, beyond which a reduction was observed. For 3-day-cured specimens, M_r increased with the number of W-D cycles. W-D action produced a greater detrimental effect on 28-day-cured specimens than on 3-day-cured specimens. The M_r values of 28-day-cured specimens subjected to 30 cycles were approximately 5% lower than the corresponding M_r values of specimens without any W-D cycles. The M_r values of 3-day-cured specimens subjected to 30 W-D cycles, however, increased approximately 55% compared with the corresponding M_r values of specimens with no W-D cycles. Also, it was found that 12 to 30 W-D cycles could be considered adequate to have a noticeable negative effect on 28-day-cured specimens; however, more than 30 cycles are needed for 3-day-cured specimens. Additionally, the positive effect of curing time was more dominant on 3-day-cured specimens, and the detrimental effect of W-D cycles was more influential on 28-day-cured specimens.

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References

NCHRP Final Report, Project 1-26: Calibrated Mechanistic Structural Analysis Procedures for Pavements. TRB, National Research Council, Washington, D.C., May 1992.

Uzan

Permanent Deformation of a Granular Base Material. In Transportation Research Record: Journal of the Transportation Research Board, No. 1673, TRB, National Research Council, Washington, D.C., 1999, pp. 89–94.

Resilient Modulus of Fly Ash Stabilized Aggregates. Master’s thesis. University of Oklahoma, Norman, 1995.

Pandey

K. K.

Evaluation of Resilient Modulus and Layer Coefficients of a Coal Ash Stabilized Marginal Aggregate Base for AASHTO Flexible Pavement Design. Ph.D. dissertation. University of Oklahoma, Norman, 1996.

Ingles

O. G.

, and Metcalf

J. B.

. Soil Stabilization—Principles and Practice. Halsted Press, New York.

Majko

M. R.

Fly Ash in Soil Stabilization and as an Engineered Construction Material. http://www.geocities.com/capecanaveral/launchpad/2095/soilstab.htm. Accessed Oct. 5, 2000.

AASHTO Guide Design for Pavement Structures. AASHTO, Washington, D.C., 1986.

Laguros

J. G.

, and Keshawarz

M. S.

. Construction Performance of the Stabilized Base Course on U.S. 77 Ponca City, Kay County. Final Report ODOT No. 83-07-02, ORA 155-487. University of Oklahoma, Norman, 1987.

Nunan

, and Humphrey

. A Review and Experimentation of Gravel Stabilization Methods. Technical Report 90-2. Technical Services Division, Maine Department of Transportation, Orono, July 1990.

10.

Miller

A. G.

, Zaman

M. M.

, Rahman

, and Tan

K. N.

. Laboratory and Field Evaluation of Soil Stabilization Using Cement Kiln Dust. Draft Report, Item 2144, ORA 125-5693. Submitted to Oklahoma Department of Transportation, Oklahoma City, February 1999.

11.

Zaman

M. M.

, Zhu

J.-H.

, and Laguros

J. G.

. Durability Effects on Resilient Moduli of Stabilized Aggregate Base. In Transportation Research Record: Journal of the Transportation Research Board, No. 1687, TRB, National Research Council, Washington, D.C., 1999, pp. 29–38.

12.

Little

D. N.

, Males

E. H.

, Pursinski

J. R.

, and Stewart

. Cementitious Stabilization. http://www.nationalacademies.org/trb/publications/millennium/00016.pdf. Accessed Jan. 10, 2001.

13.

Huffman

G. G.

, Bridges

K. F.

, Ganser

R. W.

, Holtzman

A. M.

, and Merritt

M. L.

. Geology and Mineral Resources of Marshall County, Oklahoma. Oklahoma Geological Survey, Bulletin 142. University of Oklahoma Press, Norman, 1987.

14.

Chen

D. H.

Resilient Moduli of Aggregate Bases and a Mechanistic-Empirical Methodology for Flexible Pavement. Ph.D. dissertation. University of Oklahoma, Norman, 1994.

15.

Determining the Resilient Modulus of Soils and Aggregate Materials. AASHTO Part II Test Methods, Designation T292-91. AASHTO, Washington, D.C., 1995, pp. 779–793

16.

NCHRP Final Report, Project 1-28: Laboratory Determination of Resilient Modulus for Flexible Pavement Design. TRB, National Research Council, Washington, D.C., June 1997.

17.

Determining the Resilient Modulus of Soils and Aggregate Materials. AASHTO Part II Test Methods, Designation T307-99. AASHTO, Washington, D.C., 1999, pp. 733–758.