This investigation was performed to develop technology for manufacturing cast-concrete products using Class F fly ash, coal-combustion bottom ash, and used foundry sand. A total of 18 mixture proportions with and without the by-products was developed for manufacture of bricks, blocks, and paving stones. Replacement rates, by mass, for sand with either bottom ash or used foundry sand were 25 and 35%. Replacement rates, by mass, for portland cement with fly ash were 25 and 35% for bricks and blocks, and 15 and 25% for paving stones. Analysis of test data revealed that bricks with up to 25% replacement of cement and blocks with up to 25% replacement of cement and sand with recycled materials are suitable for use in both cold and warm climates. Other bricks and blocks were appropriate for building interior walls in cold regions and both interior and exterior walls in warm regions. Paving stones with 15% replacement of cement with fly ash showed higher strength, freezing and thawing resistance, and abrasion resistance than the control specimens.
This investigation was conducted to collect the state-of-the-art information on strength and durability of roller-compacted concrete (RCC) for pavement construction made with and without supplementary cementitious materials, and to describe the construction experience grained in two pavement projects (Project I and Project II) recently completed in Wisconsin. Project I deals with performance of conventional high-volume fly ash (HVFA) concrete pavement having a roller-compacted, no-fines permeable base course containing fly ash obtained from a SO 2 control technology (dry desulphuring process), and Project II deals with RCC pavement (RCCP) containing 30% ASTM Class C fly ash. Past studies have shown that mechanical behavior of RCC pavement is similar to that of conventional paving concrete. However, non air-entrained RCC is susceptible to freezing and thawing (F & T) damage if critically saturated when subjected to freezing actions. Laboratory testing of specimens derived from the pavements showed excellent results for conventional HVFA pavement, and satisfactory performance of the RCCP
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