Settlement characteristics of landfill wastes

Successful redevelopment on old landfill sites relies heavily on predictive models of engineering behaviour, particularly the long-term settlement characteristics. Predicting the settlement of recently placed waste landfills has become a vital element of effective landfill design. Sites containing waste landfill of varying age have been monitored for over 20 years by the Building Research Establishment and the settlement data are summarized. The relationship between settlement and leachate levels in landfill is illustrated. Where older landfills have been redeveloped, ground improvement techniques have been used to improve geotechnical properties with the principal aim of reducing compressibility and post-construction settlements. The effect of surcharge and proprietary ground treatment on long-term settlement and the use of logarithmic creep compression rate parameters to predict long-term settlement are discussed.