Effects of microwave curing on the compressive strength development and hydration of cement-granulated blast furnace slag composite system

To investigate the effects of microwave curing on the compressive strength development of mortar prepared with cement-Granulated Blast Furnace Slag (GBFS) composite binder and the underlying mechanism, the evolution of temperature and water to binder ratio during the curing, the hydration products and microstructure of composite system were studied. The results show that with the increase of the GBFS content the highest temperature achieved during microwave curing and the final water to binder ratios are reduced slightly. Through the surface tension test, the existence of non-thermal effect of microwave in composite system is indirectly proved. Compared with steam curing, microwave is easier to promote the carbonation of composite binder. In addition to the acceleration of hydration at early ages, the decrease of the number of harmful pores is an important factor for the improvement of compressive strength of mortar prepared with cement-GBFS composite binder. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

With the increase of GBFS content, the highest temperature and final water to binder ratios during microwave curing are slightly reduced. The existence of non-thermal effect of microwave in the composite system is indirectly proved through surface tension test. Compared with steam curing, microwave is easier to promote carbonation, and the reduction of harmful pores is an important factor for improving the compressive strength of mortar prepared with cement-GBFS composite binder.