Solidification of Sediments Deposited in Reservoirs with Cement and Fly Ash for Road Construction

This paper explores the stabilisation of dredged lakebed sediments with ordinary portland cement and fly ash to repurpose the sediment as road pavement construction material. Data are obtained from previous studies on sediments collected from Phayao Lake and Huai Mae Phong Reservoir in Phayao province, and Mae Sab Reservoir in Chiang Mai province in Thailand. Empirical correlations are established between strength and stiffness parameters of the chemically stabilised dredged sediments intended for transportation and geotechnical applications. The strength and stiffness parameters considered in this study include unconfined compressive strength, the California bearing ratio, and the resilient modulus. The influence of curing period on strength development is determined. New strength and stiffness correlations are proposed and presented to describe stabilised soils based on the extensive experimental data. Optimised sediment/cement/fly ash mixtures which proved to be most effective in generating appropriated material strengths for road construction are reported.