RI 8773 Mechanical Properties of Some Portland Cement Concretes Made With Coal and Coal Waste as Aggregates

A bench-scale evaluation of coal and coal waste materials as aggregate materials for use in longwall mine supports was undertaken as part of the Bureau of Mines Health and Safety program on ground control. Performance data were obtained on portland cement concretes (PCC) prepared with coal and coal wastes as aggregate materials. The effects of high-early-strength accelerators on strength and creep and of superplasticizers on strength properties of PCC formulated with coal and coal waste were investigated. Concrete formulated with a high-early-strength accelerator and coal and coal waste has 20 and 40 pet greater compressive strength, respectively, than the control samples without admixture. A concrete formulated with coal waste and the high-early-strength accelerator, using four bags of cement per cubic yard and a water-cement ratio of 1.0, had the lowest creep value of all the coal- and coal-waste-formulated PCC's tested.