Construction of a large oedometer for MSW and non-conventional materials testing

The design, construction and evaluation of a large consolidometer for testing municipal solid waste (MSW) and other non-conventional materials is proposed. The apparatus features leachate recirculation and biogas production monitoring. Furthermore, it is equipped with moisture content sensors, suction and at-rest lateral earth pressure measuring capabilities. Fresh MSW samples were collected from a metropolitan centre landfill and were used to test performance and conduct MSW mechanical behaviour analyses. Values of vertical stress (σ_z) ranging from 10 to 1000 kPa were employed in the test, which lasted for approximately 1 year. The results show that the secondary compression index was affected by sample saturation and that biogas composition acted as an indicator of the MSW phase of decomposition. Lateral earth pressure at rest values increased with σ_z, although they decreased over time for the same loading stage. Values of primary compression and swelling indexes (c_c and c_e, respectively) are close to those reported in the literature for similar material.