Compaction Analysis of Municipal Solid Waste
Project Summary: This study was conducted to investigate compaction characteristics of municipal solid waste (MSW). Tests were conducted in the laboratory and in the field as a function of moisture content, compactive effort, and seasonal effects. Laboratory tests were conducted on manufactured wastes using modified and 4X modified efforts. Field tests were conducted at a MSW landfill in Michigan on incoming wastes without modifications to size, shape, or composition, using typical operational compaction equipment and procedures. Laboratory testing provides an effective means for evaluating trends in compaction characteristics of wastes, while field testing allows for identifying and ascertaining specific quantitative values of significant compaction parameters. Field tests generally included higher efforts and resulted in higher unit weights at higher water contents than the laboratory tests. Moisture addition to wastes in the field was more effective in winter than summer due to dry initial conditions and potential thawing and softening of wastes. Soil compaction theory was reasonably applicable to MSW with the exception that the Gs of waste solids increased with compactive effort resulting in steep degree of saturation curves and low change in wopt between efforts. Moisture addition to wastes during compaction increased workability, unit weight, and amount of incoming wastes disposed, and reduced compaction time. Moisture addition during compaction provides an effective means of uniform moisture delivery to wastes and an alternative method for introducing leachate, water, or other liquids to wastes for leachate recirculation and bioreactor landfill applications. The combined effects have significant environmental and economic implications for landfill operations.

Principal Investigator: Jim Hanson and Nazli Yesiller

Funding Agency: Office of Naval Research and Partner Landfill (Riverview Land Preserve)

Hanson, J. L., Yesiller, N., Von Stockhausen, S. A., and Wong, W. W., (2010), "Compaction Characteristics of Municipal Solid Waste," Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 136, No. 8, p. 1095-1102. [Download pdf]

Yesiller, N., Wong, W. W., and Hanson, J. L., (2010), "Hydraulic Conductivity of Municipal Solid Waste as a Function of Placement Conditions," Proceedings Sixth International Conference on Environmental Geotechnics, New Delhi, India.