Concrete production uses a considerable amount of natural resources that cannot be replaced or replenished. With landfills being created at an alarming rate compounded with the increased cost of dumping trash, the need for recycling has reached an all-time high. It is logical to try to find an acceptable replacement for material that is normally consumed with one that is typically thrown away in landfills. Thus, this study considers the use of recycled tire rubber as a fine aggregate in place of sand in concrete. Novel concrete materials with a unique balance of stiffness and toughness would be valuable in many new and existing applications. Due to the scale of the building and construction market, especially in regions such as China, natural resources such as sand and gravel are currently being consumed on an exponential scale. Furthermore, acceptance of this type of product would help transform our society to a more sustainable environment with a significant reduction in the amount of tires going into landfills and consequently conservation of natural resources, such as sand.
A statistical design of experiments utilizing a JMP Custom Design was generated for this study. Mix factors include the rubber to sand volume % proportion and the super plasticizer concentration. The water to cement ratio also needed to be adjusted in order to compensate for the increased water absorption of rubber versus sand. Responses of interest include work ability (slump), density (unit weight), and compressive testing (to measure strength, toughness, and the modulus of elasticity of the mixes). Statistical analyses of the results were performed using Excel and JMP.