Effect of Nano-TiO2 on Capillary Water Absorption of Recycled Aggregate Concrete

To improve the durability performance of recycled aggregate concrete in actual use, this paper uses nano-TiO2-modified coarse to study, through experiments, effects nano-TiO2 on pore distribution after freeze–thaw. The capillary-water-absorption law was used as evaluation index. prepared with different contents nano-TiO2, and changes 24 h capillary water absorption porosity freeze–thaw cycles were analysed. With help high-resolution image recognition binary-image-processing technology, before obtained. Through analysis water-absorption data at times, initial rate, S1, is reacted prediction model under established. results show that action cycles, increases increase RCA substitution rate decreases content. After 150 cumulative RC25-NT1.2 decreased by 25.52% 14.57%, respectively, compared test block without nanomaterials. It found has a prominent role modifying concrete. Nano-TiO2 can reduce alleviate negative impact cycles. observed scanning electron microscopy large amount C–S–H gel produced inside mixed which bonded internal pores cracks form dense structure.