Limit Analysis of the Reinforced Soil and Modeling Strength of Solid Waste in Landfills Using the Concepts of Soil Reinforcement

Engineered reinforcement of soils has revolutionized the methods for constructing soil retaining structures, man-made slopes, and development of foundation soils. Both the geosynthetic reinforcement in the form of geogrid or woven geotextiles and metal strips have been very successful in construction. Fiber reinforcement, while it caught the attention of some researchers, never proved to be as useful, and the amount of research generated on the topic today is disproportional to the utility of the method in engineering practice. Development of the models describing the strength of fiber-reinforced soils, however, forced engineers to consider such issues as the yield condition, flow rule, and anisotropy. All of these are important in considering stability of municipal solid waste landfill slopes. Although a comprehensive yield condition for municipal solid waste has not been developed yet, an effort is presented indicating how the existing methods describing reinforced soils can be used to develop an anisotropic yield condition suitable for the description of solid waste. It will be shown that a homogenization scheme, sometimes referred to as the principle of macro-homogeneity, is a useful tool in developing the yield surfaces suitable for fiber-reinforced composites, thus also for fibrous solid waste.