Summary: Ahmet H. Aydilek, 1 Tuncer B. Edil, 1 Patrick J. Fox2
Consolidation Characteristics of Wastewater Sludge
Reference: Aydilek, A. H., Edil, T. B., and Fox, P. J., "Consolidation Characteristics
of Wastewater Sludge", Geotechnics of High Water Content Materials, ASTM STP
1374, T. B. Edil and P. J. Fox, Eds., American Society for Testing and Materials, West
Conshohocken, PA, 1999.
Abstract: Capping is a cost-effective remediation method for soft contaminated sludge.
The Madison Metropolitan Sewerage District evaluated different remediation alternatives
to treat its polychlorinated biphenyl (PCB) contaminated sludge and the U.S. EPA agreed
to permit capping as the method of remediation. Design of the cap required knowledge
of the consolidation behavior of the sludge. In order to analyze this behavior, a series of
consolidation tests was performed. The laboratory testing program included three large-
scale consolidation tests and four conventional oedometer tests. Consolidation settlement
of the sludge was observed in two field test cells capped with a wood chip/soil mixture
which was reinforced with a woven geotextile. Instrumentation of the test cells included
settlement plates, surface survey markers, and piezometers at different depths in the
sludge. Laboratory and field observations were compared with results from conventional
consolidation theory and a nonlinear finite-strain (large strain) numerical model (CS2).
Conventional theory exhibited some limitations in analyzing the results and