Exploring the effect of the micropore on the microstructure development of low water-cement ratio composite (LW/B-CC) subjected to microwave pre-curing
Siyu Wang, Feixiang Chen, Min Yu, Teng Liu, Jinyun Zhu, Tianyi Yin, Kangning Liu, Rui Yu, Rui Yu
Abstract
Microwave pre-curing, as an energy-saving and efficient pre-curing method, is employed and further optimized to produce low water-cement ratio composite (LW/B-CC) in this study. Theoretically, by replacing part of the coarse sand with porous zeolite sand, the potential stress concentration induced by microwave pre-curing and the crack risk in LW/B-CC can be reduced, which is beneficial for promoting the application of microwave curing strategy in practice. The obtained results show that the addition of zeolite can indeed achieve a win-win situation for early and late strength . This is the combined effect of space and time, working together in a four-dimensional (4-D) perspective: in space, Zeolite balanced the temperature difference at different positions of the sample during microwave treatment, reducing cracks caused by differences in thermal expansion coefficients of the matrix; in time, Zeolite reduces the porosity by extending the migration rate of water molecules to large pores and the water molecule backflow during microwave pre-curing. Finally, based on the proposed new idea in this study, the microstructure of LW/B-CC can be well optimized during microwave curing process.