Sponsor: Michigan Department of Environmental Quality (MIDEQ)
PI: Qingli Dai
In the recent decade, the resuse of scrap tire rubbers in concrete has attracted much interests of researchers and practitioners. The practical efforts can reduce the environmental impact. In general, the rubber-modified concrete can improve static and dynamic fracture toughness and decrease brittleness. Particularly, the mixed rubber particles (mesh size #10-#30) will introduce the uniformly distributed “elastic entrained particles”, which can release internal expansive stress due to freeze-thaw damage and chemical attack for improved durability. In addition, the surface-treated rubber particles have good bonding strength with cement paste.
This project will develop mixture design for PVA reinforced rubber concrete with exceptional mechanical and durability performance. Following current rubber particle treatment for improved bonding strength with cement concrete, this research will be further conducted to develop PVA filber-reinforced rubber concrete with a high content of rubber particles (up to 50% volumetric replacement of fine aggregates). With increased amounts of rubber particles in concrete, the PVA fibers will be added as reinforcement to meet the strength and stiffness requirements.
The dispersed rubber particles and PVA fibers will not only improve the elasticity and enhance the fracture toughness by interfering crack propagation, but also reduce the transport property and improve durability under freeze-thaw and chemical attack conditions. The rubber particles with mesh size 10 (2.54 mm) to 30 (0.84 mm) will be used with the volume percentage (15-50%) of fine aggregates in concrete. In the lab, fiber-reinforced rubber concrete with four rubber contents will be designed, prepared and tested for early-stage property development, as well as mechanical and durability performance. Following the lab testing studies, a field construction project is also proposed to use the rubber-reinforced cement concrete to pave Laketon Avenue in Muskegon, MI by collaborating with the City of Muskegon and a material supply company.
The main objectives of this project are to develop a practical approach for PVA fiber-reinforced rubber concrete design and to conduct the lab and field performance studies to facilitate the material field applications.