This research aims to clarify the intrinsic effect of microwave pre-curing on the hydration kinetics and microstructure development of Ultra-High Performance Concrete (UHPC). Six hours after casting, the UHPC samples are subjected to microwave pre-curing for 60–240 s. Then, the macro and micro characteristics of the cured UHPC are evaluated. The observed experimental results show that the microwave treatment can create a dense shell around the cured UHPC's periphery, which can resist the lateral deformation of the specimen and guarantee the excellent mechanical properties of the treated sample. Moreover, when steel fibres are included into UHPC, the reflection and shielding effect of the 3D fibres network can significantly block the promotion effect of microwave on the strength development of UHPFRC. Additionally, due to the high energy of microwave, high polymerization hydration products and advanced pore structure (micro and meso scales) can be observed in the pre-cured UHPC. 

Hydration kinetics and microstructure development of Ultra-High Performance Concrete (UHPC) subjected to microwave pre-curing

Influence of different curing methods on the compressive strength of ultra-high-performance concrete: A comprehensive review

The effect of curing regimes on physico-mechanical, microstructural and durability properties of alkali-activated materials: A review

ABSTRACT There is an urgent need to recycle glass fiber-reinforced polymer (GFRP) and carbon fiber-reinforced polymer (CFRP) composites due to environmental challenges caused by incineration and traditional landfilling. This review incorporates an overview of the latest knowledge on the recycling techniques for different GFRP and CFRP composites. The applications of these chopped fibers are limited due to significant depreciation in their mechanical properties after recycling. The high-value applications of the composites remanufactured through recycled fibers are outlined. This review also incorporates the present challenges and modern trends in the recycling of fiber-reinforced composites. It is expected that further innovations in recycling technologies will be helpful to establish a circular economy and sustainable benign environment. Graphical abstract

Zhou Hang

Papers

Recent development of microwave applications for concrete treatment

An analysis model for the temperature and residual stress of tunnel liner exposed to fire