Development of Green Engineered Cementitious Composites for Sustainable Infrastructure Systems

Over the last decade, enormous strides have been made in creating engineered cementitious composites (ECC) with extreme tensile ductility, on the order of several hundred times that of normal concrete or fiber reinforced concrete (FRC). Current ECC investigations include load carrying structural members in new infrastructure systems, as well as for repair and retrofitting of existing structures. ECC design has been built on the paradigm of the relationships between material microstructures, processing, material properties, and performance. This paradigm has worked very well in creating various versions of ECC that can be processed by self-consolidated casting, spraying, and extrusion. This paper describes preliminary results of an initial attempt at creating green ECCs, ECCs that maintain the tensile ductility characteristics, but which also incorporate sustainability considerations in the design of these materials for infrastructure applications. Sustainable material design integrates microstructure tailoring with life cycle analysis based on social, environmental, and economic (SEE) indicators. The framework of green ECC development is described. Some preliminary experimental results of the effect of cement substitution and fiber substitution with industrial by-products on the mechanical properties are reported. It is demonstrated that the concept of green ECC for sustainable infrastructures is feasible, although an extensive amount of research remains ahead.