Engineering Properties of Compacted Fly Ash

by Donald H. Gray, Assoc. Prof. of Civ. Engrg.; Univ. of Michigan, Ann Arbor, MI,
Yen-Kuang Lin, Proj. Engr.; Soil and Materials Engineers, Inc., Detroit, MI,

Serial Information: Journal of the Soil Mechanics and Foundations Division, 1972, Vol. 98, Issue 4, Pg. 361-380

Document Type: Journal Paper


The lower compacted density of fly ash relative to conventional earthfill recommends its use when a fill or embankment must be constructed over soft, compressible ground. Field evidence to date indicates that compressibility or settlement of compacted fly ash fills is not significant. Long-term field settlements cannot be predicted satisfactorily on the basis of short-term laboratory tests because fly ash exhibits age-hardening or pozzolanic properties. Low-level additions of lime to the fly ash before compaction accentuate this behavior. Frost susceptibility likewise is not as serious a problem in compacted fly ash as might be presumed from its grain size distribution. Gradation alone does not suffice as a criterion of frost susceptibility; pozollanic properties also play an important role. Undesirable frost heave in compacted fly ash can be reduced to tolerable levels by addition of lime or cement.

Subject Headings: Earth fills | Compaction (material) | Fly ash | Compression | Soft soils | Lime | Frost | Compacted soils

Services: Buy this book/Buy this article


Return to search