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.

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The coefficient of thermal expansion (CTE) was determined for a typical concrete-paving mixture made with six different types of coarse aggregates belonging to the basic class of glacial gravel, quartzite, granite, diabase, basalt, and dolomite. The CTE, compressive strength, and splitting tensile strength of fifteen different concrete mixtures were determined at the age of 28 days. Two parameters, CTE and splitting tensile strength, are the basic input in AASHTO's new mechanistic-empirical pavement design method. The study revealed a noticeable variation in the values of the CTE of concrete with different types of aggregates. Concrete with quartzite aggregate had the highest value of the CTE followed by dolomite, glacial gravel, granite, and diabase or basalt. The estimated value of the splitting tensile strength of concrete, considering its compressive strength and using AASHTO's Mechanistic-Empirical Pavement Design Guide for Level 2 design of concrete pavements was discovered to be significantly lower (17-31%) than its actual experimentally determined value.

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