Pre-Saturation Technique of the Recycled Aggregates:Solution to the Water Absorption Drawback in theRecycled Concrete Manufacture

Materials

Andrés Juan-Valdés¹  M. Ignacio Guerra-Romero¹  Julia Mª Morán-del Pozo¹  Julia García-González¹  Desirée Rodríguez-Robles¹ 

[1] Superior and Technical School of Agricultural Engineering, University of Leon,Avenida de Portugal 41, 24071 Leon, Spain;

关键词: construction and demolition waste;    compressive strength;    slump test;    moisture state of recycled coarse aggregate;   

DOI  :  10.3390/ma7096224

来源: DOAJ

【 摘 要 】

The replacement of natural aggregates by recycled aggregates in the concrete manufacturing has been spreading worldwide as a recycling method to counteract the large amount of construction and demolition waste. Although legislation in this field is still not well developed, many investigations demonstrate the possibilities of success of this trend given that concrete with satisfactory mechanical and durability properties could be achieved. However, recycled aggregates present a low quality compared to natural aggregates, the water absorption being their main drawback. When used untreated in concrete mix, the recycled aggregate absorb part of the water initially calculated for the cement hydration, which will adversely affect some characteristics of the recycled concrete. This article seeks to demonstrate that the technique of pre-saturation is able to solve the aforementioned problem. In order to do so, the water absorption of the aggregates was tested to determine the necessary period of soaking to bring the recycled aggregates into a state of suitable humidity for their incorporation into the mixture. Moreover, several concrete mixes were made with different replacement percentages of natural aggregate and various periods of pre-saturation. The consistency and compressive strength of the concrete mixes were tested to verify the feasibility of the proposed technique.

【 授权许可】

Unknown