Mechanical Properties and Fluidity of Grouting Material with Recycled Fine Aggregate at Different Temperature

Abstract

At the present stage, the demolition industry of old building has produced more and more wastes. From the perspective of environment, economy and society, the amount of waste has reached an unacceptable level. Therefore, the resource utilization of waste has become a research hotspot. At present, as cement-based materials are the most widely used building materials in the world, the production of recycled aggregate from waste materials is an effective way to reuse cement-based materials. The fluidity, flexural strength and compressive strength of recycled fine aggregate grouting materials at 20 ℃, 30 ℃ and 40 ℃ were studied in this paper. The water cement ratio of the three grouting materials is designed to be 0.29, 0.37 and 0.45. The amount of recycled fine aggregate is 0%, 25% and 50% respectively. The results revealed that both the replacement of recycled fine aggregate and the high temperature had an adverse effect on the fluidity of grouting material. When the replacement of recycled fine aggregate increased, the initial fluidity decreased, also the fluidity after 30min. A rise in temperature had a similar effect. At 20°C, there is no obvious evidence that the amount of recycled fine aggregate affects the compressive strength and the flexural strength. Under the condition of 40℃, when the recycled sand content is 50%, the flexural strength of 28 days decreases. At 40℃, when the recycled sand content is 50%, the compressive strength of 3 days and 28 days decreases.