Use of Fly Ash in Road Constructions

Abstract

The aim of this Use Of Fly Ash In Road Constructions study was to compare the different sections regarding stiffness and environmental impact. The environmental impact of the road was estimated from soil water and leachate from the road and an initial leaching of K, Na, Cl and SO 4 was found from the lysimeters.

The estimated total leaching from the road was not corresponding to the laboratory leaching tests performed on the ash (L/S10). The bearing capacity of the sections was measured with falling weight deflectometer at four different occasions and the bearing capacity increased with time and ash content. During snow-melting periods, the reference sections showed different disruptions but the test sections were unaffected.

Conclusion

The overall evaluation of the roadway in phase two of the three-phase program indicates good performance of the LFA base despite the poor quality of construction. This performance indicates that a LFA stabilized granular material is a viable option for replacement of a bituminous material in base course construction. An economic analysis of the phase two project indicated significant savings of approximately $30,000 per 2-lane mile by using a LFA stabilized material instead of a bituminous material for the base course construction.