Mechanical Properties of Municipal Solid Waste in Lagos Metropolis, a Case Study of Ikeja

Abstract

Studying the mechanical behavior of Municipal Solid Waste (MSW) is accompanied by many complications. This work attempts at studying some properties of municipal waste recovered from Ikeja Municipal Area in Lagos, Nigeria. Knowledge of the likely ranges of mechanical properties of waste is required to assess potential modes of failure and hence to design the landfill, as the stability of waste mass is one of the major concerns associated with the design of landfill expansion in Lagos. Mechanical properties such as green compression, permeability, bulk density, porosity and shear strength were determined experimentally for three different waste samples A, B and C at different moisture contents. The values of the experimental results for the different moisture contents are given as follows: green compression: Maximum 65 N/m2, minimum 24 N/m2; permeability: maximum 209.56cm/sec., minimum 73.17 cm/sec.; bulk density: maximum 2.364 g/cm3, minimum 0.6514 g/cm3; porosity: maximum 204.09, minimum 83.19 and shear strength: maximum 85 N/m2, minimum 45 N/m2. The results obtained showed that green compression, shear strength, permeability, bulk density, and porosity all have varying values dependent on the constituents of the wastes. The results also showed that sample C has both the highest and lowest porosities. On a plot of experimental values obtained, all the sample wastes converge at the same point of moisture content of 25%. This shows that shear strength property becomes similar as moisture content increases. It can also be concluded that different moisture contents influence the mechanical properties of solid waste.