01661252

Component

Incineration bottom ash (IBA), which is produced in the process of municipal solid waste incineration, need to be recycled properly in order to avoid environmental pollution and provide appropriate road materials. In this study, mineralogical characterizations, physical properties and environmental impact of IBA were evaluated by X-ray diffraction (XRD), basic property tests and leaching tests. And a series of engineering performance tests of IBA and IBA treated two types of subgrade soils, including compaction tests, California bearing ration (CBR) tests, unconfined compressive strength (UCS) tests, resilient modulus tests and repeated load triaxial permanent deformation tests, were conducted. It was observed that weathering time has a significant effect on properties of IBA, such as decrease of cementitious activities, bulk density, pH and conductivity, and increase of water absorption. The evaluation demonstrates that IBA content and curing time both are the influence factors due to the interlock strength and gelatinous substances of IBA. As IBA content increases, the maximum dry density decreases, while the optimum moisture content increases; CBR, UCS and resilient modulus after water damage increase; and the deformations under soaking and load are significantly reduced, except that permanent deformation of IBA treated clay slightly increase. And IBA have different effects on the performance of clay and silt due to their different mineral compositions. With longer curing time, IBA treated soils will achieve better properties of strength, anti-water damage and anti-deformation. IBA with longer than 90-days weathering and more than content of 30% is recommended for treating subgrade soils.

This paper was sponsored by TRB committee AFP40 Standing Committee on Geo-Environmental Processes.

18-02388

English

15p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; References; Tables

Bottom ash; Environmental impacts; Materials tests; Soil stabilization; Soils; Subgrade materials; Weathering

Incineration

Environment; Geotechnology; Highways; Materials

Transportation Research Board Annual Meeting 2018 Paper #18-02388

TRIS, TRB, ATRI

Jan 8 2018 10:35AM