Solid waste

landfill A landfill site, also known as a tip, dump, rubbish dump, garbage dump, or dumping ground, is a site for the disposal of waste materials. Landfill is the oldest and most common form of waste disposal, although the systematic burial of the waste ...

s can be affected by seismic activity. The tension in a

landfill liner A landfill liner, or composite liner, is intended to be a low permeable barrier, which is laid down under engineered landfill sites. Until it deteriorates, the liner retards migration of leachate, and its toxic constituents, into underlying aquif ...

rises significantly during an

earthquake An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...

, and can lead to stretching or tearing of the material. The top of the landfill may crack, and methane collection systems can be moved relative to the cover.Matasovic, N.; Kavazanjian Jr., E. (2006) "Seismic Response of a Composite Landfill Cover" ''Journal of Geotechnical and Geoenvironmental Engineering'' V. 132(4): 448-455. Increasing the depth of a waste column typically leads to a decrease in the

ground acceleration Peak ground acceleration (PGA) is equal to the maximum ground acceleration that occurred during earthquake shaking at a location. PGA is equal to the amplitude of the largest absolute acceleration recorded on an wikt:accelerogram, accelerogram at a ...

felt at the surface of that landfill during an earthquake.Bray, J.D.; Augello, A.J.; Leonards, G.A.; Repetto, P.C.; Byrne, R.J. (1995) "Seismic Stability Procedures for Solid-Waste Landfills" ''Journal of Geotechnical Engineering'' V. 121(2): 139-151. The weight of waste is important in the analysis of landfill liner puncture and pipe crushing during an earthquake.Choudhury, D.;Savoikar, P. (2009) "Simplified Method to Characterize Municipal Solid Waste Properties Under Seismic Conditions" ''Waste Management'' V. 29(2):924-933. Unstable rock under landfills such as limestone may yield during an earthquake, leading to a partial collapse of the fill.Krinitzsky, E.L.;Hynes, M.E;Franklin, A.G (1997) "Earthquake Safety Evaluation of Sanitary Landfills" ''Engineering Geology'' V. 46(2): 143-156. A major concern in this case would be the potential contamination of water sources that may be located below the landfill.

Modeling

In a pseudostatic

slope stability analysis Slope stability analysis is a static or dynamic, analytical or empirical method to evaluate the stability of earth and rock-fill dams, embankments, excavated slopes, and natural slopes in soil and rock. Slope stability refers to the condition of i ...

, the earthquake is modeled as a constant horizontal force. The fact that the earthquake force is modeled as a constant force acting in one direction, represents this model's major limitation. In a Newmark permanent deformation mathematical analysis, movement of a landfill occurs when a driving force on the landfill is greater than its resisting force. A shaking table laboratory test works to explore the strength characteristics at interfaces between different components of the landfill. Of primary concern is the contact between soil and landfill liner, as this is usually considered to be a weak point in the system. A dynamic centrifuge test works to model the landfill in a scaled-down form. Typically in this approach, a small simplified landfill is constructed in a test box. During this testing, earthquake loading is simulated on the sample landfill. A major application of this type of testing is to observe the behavior of landfill liners during ground shaking. The uniqueness of many landfills makes it difficult to apply test results from one site to another. Measuring properties of landfills such as waste unit weight could lead to health concerns, as the handling of waste could be dangerous. Accessing this waste would likely involve damaging the cover liner, which could compromise the ability of the system to function properly. Landfills are systems which change over time, so periodic evaluations may be necessary.

References

{{DEFAULTSORT:Seismic Response Of Landfill Landfill Seismology