Municipal incinerated solid waste bottom ash as sustainable construction material in the construction of flexible pavements

The main factors driving the reuse of construction waste in pavement are the rapid decline in the availability of conventional aggregates, increasing haulage distances, and the scarcity of landfill sites. Municipal Solid Waste Incineration (MSWI) is a popular solid waste treatment method that can reduce landfill clogging. In an attempt to reduce waste accumulation and conserve natural resources, this study evaluated the effectiveness and feasibility of using MSWI-BA as a partial replacement for fine aggregate in Bitumen Concrete Grade II (BC-II), a closely graded wearing course widely used in India. The optimal asphalt content of asphalt mixes for different MSWI-BA percentages was determined using the Marshall mix design. Tests to determine the resilient modulus, indirect tensile strength, resistance to moisture-induced damage, and rut resistance using a dynamic creep test were conducted to study the performance of the asphalt mixes with various MSWI-BA contents. From the research, it is advisable to replace the fine aggregates with MSWI-BA up to 20% to obtain a physically strong, higher performing, and economically efficient bituminous concrete layer. The toxicity characteristic leaching procedure test results indicated that the concentration of heavy metals and the levels of toxicity were significantly reduced after it was mixed with asphalt mix.