Employing vegetable fibres as conveyors of healing in Ultra High Performance Concrete

Department

Department of Civil and Environmental Engineering, Politecnico of Milan

Main research activities/topics/projects

In pursue of greener cementitious composites the research aims at studying the implementation f vegetable fibers as conveyor of healing. Such use has an enormous advantage and has rarely been pursued intentionally. The cost of vegetable fibers is very low and they usually require just a wash in hot water to be incorporated into the concrete mix. These types of fiber have a porous hierarchical structure formed by several different wall layers (each one with a singular chemical composition). The porous size on those structure ranges between 0.2 nm and 30 nm and until 8 μm form lumen size. This variable porous media promotes a high and fast water absorption followed by a slow and controlled desorption process. The absorption happens during the molding process, interaction with the water from the mix design. The desorption is triggered off by several phenomena such as temperature elevation, matrix water evaporation, matrix necessities (more water for hydration reactions) The research wants to assess the role of vegetable fibers, acting as carriers of the water, which is the main healing agent in all autogenous and most autonomous healing processes in cement based materials, as well as nucleation spots for calcium carbonate deposition, thanks to their ability to maintain a highly moist micro-environment.

Working language

Italian and English

Special entry requirements

Computer skills: use of Matlab tools and finite elements. Lab experience: capacity to run experimental activity independently

Duration in months (min-max)

PhD Sanwhich: 6-12