An overview of study on recycled aggregate concrete in China (1996-2011)

Properties and composition of recycled aggregates from construction and demolition waste suitable for concrete production

This paper discusses the properties of RCA, the effects of RCA use on concrete material properties, and the large scale impact of RCA on structural members. The review study yielded the following findings in regards to concrete material properties: (1) replacing NA in concrete with RCA decreases the compressive strength, but yields comparable splitting tensile strength; (2) the modulus of rupture for RCA concrete was slightly less than that of conventional concrete, likely due to the weakened the interfacial transition zone from residual mortar; and (3) the modulus of elasticity is also lower than expected, caused by the more ductile aggregate. As far as the structural performance is concerned, beams with RCA did experience greater midspan deflections under a service load and smaller cracking moments. However, structural beams did not seem to be as affected by RCA content as materials tests. Most of all, the ultimate moment was moderately affected by RCA content. All in all, it is confirmed that the use of RCA is likely a viable option for structural use.

https://link.springer.com/content/pdf/10.1007%2Fs40069-013-0032-5.pdf

Recycled Concrete Aggregates: A Review

This paper presents a review of the literature published so far on the use of fine aggregates from construction demolition waste used as a partial or total replacement of fine natural aggregates in concrete production. The review presents the initial works on this subject and an overview of the existing regulations. It goes on to describe the production, treatment and properties of the fine recycled aggregates (FRA). The most suitable mixing techniques for concrete with this type of aggregates are then discussed. The properties of these concrete mixes are analysed in detail, after which a few examples of structures with this type of concrete are described and compared. The acquisition of fine natural aggregates and the dumping of the fine fraction of construction and demolition waste are two serious environmental problems that can be solved simultaneously by using FRA in concrete production, a subject that is lagging behind the use of the corresponding coarse fraction.

Concrete with fine recycled aggregates: a review

An experimental study on flexural strength of reinforced concrete beams with 100% recycled concrete aggregate

In order to evaluate whether concrete with recycled aggregate can be applied for concrete structures, flexural loading tests of reinforced recycled concrete members were carried out The recycled coarse aggregate and the recycled fine aggregate were produced mainly from various reinforced concrete members of a building structure as well as from 300 mm cubic concrete specimens The properties of concrete with recycled aggregates, such as strength, Young's modulus, shrinkage, creep and shrinkage-induced stress depending on the combination of natural and recycled aggregates, curing condition, and water to binder ratio, were discussed based on a comparison with the properties of concrete with virgin aggregates Furthermore, the flexural behavior of reinforced recycled concrete beams was also discussed through comparison with the behavior of companion virgin concrete beams in which the tension reinforcement ratio, curing condition, and water to binder ratio of concrete, are the main factors The results indicate the mechanics-based possibility of utilizing recycled concrete for reinforced concrete structures under the proper design and within the proper limit of application

Takahisa Sogabe

Papers

Flexural Behavior of Reinforced Recycled Concrete Beams