Coal mine overburden soft shale as a controlled low strength material

ABSTRACT

The storage of coal mine overburden consumes vast tract of usable land with occasional slope failure and environment pollution of nearby area. In the present study, a comprehensive laboratory investigation to develop a controlled low-strength material (CLSM) using the coal mine overburden shale as the base material and fly ash and cement as the cementitious material is presented. Several CLSM mix designs were tested for compressive strength, water absorption, ultrasonic pulse velocity, slake durability index, and leachability. The CLSM is shown to have self-flowing and self-levelling consistency, low bleeding, low unit weight, good ductility, adequate strength, reasonable durability, and no undesirable leachable constituents. The developed CLSM can be considered as an effective and sustainable construction material, offering significant environmental and economic benefits.

KEYWORDS:

• Mine overburden
• fly ash
• aggregate
• controlled low-strength material
• durability
• leachability

Acknowledgements

The authors acknowledge the partial financial support provided by the Ministry of Human Resources Development, Government of India, under SPARC project titled “Geoenvironmental and geotechnical issues of coal mine overburden”

Disclosure statement

No potential conflict of interest was reported by the authors.