COMPARATIVE ANALYSIS OF THREE EMBANKMENT METHODS FOR ROAD CONSTRUCTION BY LIFE CYCLE ASSESSMENT AND COST

Abstract

In recent years, new composite geomaterials have been developed to reduce the weight of road
construction materials in soft ground and mountainous areas in Japan that are prone to ground liquefaction and
landslide. These new composite geomaterials have some problems, such as increased construction time, cost,
and adverse impacts on the environment. As a result, conventional geomaterials are usually chosen over
composite geomaterials in Japan. However, there are few researches that analyzed the environmental impacts
(for example, CO2, NOx, and SOx emissions as well as total life-cycle cost) of traditional and composite
geomaterials quantitatively from the perspective of LCA (life cycle assessment). Therefore, the purpose of this
research is to apply a LCA to estimate the total emissions of CO2, NOx, and SOx as well as the total life cycle
costs of three embankments—one constructed by the conventional method (cut and fill), one with lightweight
geomaterial mixed with expanded polystyrene beads, and one by the expanded polystyrol construction method.
All three embankments are located on a mountain road in Japan.