Performance and economic analyses of low-energy ohmic heating cured sustainable reactive powder concrete with dolomite powder as fine aggregates

Abstract

The fabrication of reactive powder concrete (RPC) has been largely restricted by the high cost of raw materials and the high energy-consuming curing method. In this work, dolomite powder was incorporated to fully replace silica sand as fine aggregates to minimize the material cost of RPC and realize green sustainable development in economic society. Moreover, sustainable reactive powder concrete (SRPC) with dolomite powder fine aggregates was cured in energy-saving mode by using low-energy ohmic heating (LEOH) curing to replace traditional high temperature steam (HTS) curing. The results showed that the curing temperature of LEOH cured sample reached up to 180 °C to reduce the curing duration within 3 h, and the implementation of 3 h LEOH curing could remarkably stimulate the compressive strength of SRPC sample to 105.8 MPa which was comparable to that cured by 3 days HTS curing. Microstructural analyses results indicated the advantages of LEOH curing on improving hydration degree and microstructure of SRPC samples with dolomite powder incorporation. A thorough economic analysis was conducted to further emphasize the quantitative effects of dolomite powder incorporation and LEOH curing on reducing the material and energy costs of SRPC construction. This work broadens the application scenario for RPC structure construction with higher efficiency and lower cost.