Geotechnical Characterization of Clinker-Stabilized Fly Ash - Coal Mine Overburden Mixes for Subbase of Mine Haul Road

Abstract

A B S T R A C TFly ash is a major by-product of thermal power plants that adversely affects land, water, and air. Its gainful utilization in many areas is being continuously explored. Use of fly ash in opencast coal mine haul road construction is one such option. This article reports detailed laboratory investigations carried out on clinker-stabilized fly ash-mine overburden mixes to evaluate their suitability for subbase of mine haul roads. Composite materials were prepared from fly ash, mine overburden, and clinker at different proportions. Proctor compaction test, unconfined compressive strength (UCS), and ultrasonic pulse velocity tests were carried out at different curing periods. UCS values were found to be strongly dependent on clinker content as well as curing period. Ultrasonic pulse velocity tests confirmed the obtained UCS results. The composite with 62% fly ash and 8% clinker content showed adequate mechanical strength suitable for the subbase of a mine haul road.

Effect of fly ash on geotechnical properties and stability of coal mine overburden dump: an overview

“…Rajak et al [59] reported that UCS value get increased by 9.34% with the addition of 20% fly ash in OB material. Few additives were added in different proportions with the fly ash-OB mix like lime [63,64,70], clinker [71,72], cement [68], GGBS [56], and kiln dust [69] to determine the UCS value. The best suitable results of UCS value under different mix proportions of OB material, fly ash, or/and additive are described in the Table 4.…”