Multi-objective optimization design of recycled aggregate …
It is a good way to use recycled aggregate produced by waste concrete to replace natural aggregate to prepare Recycled Aggregate Concrete (RAC), which improves the recycling rate of CDW and reduces the pressure of over-exploitation of natural resources. ... Research on RAC production plays a pivotal role in Chinese …
(PDF) Recycled aggregates in concrete …
Recycled concrete aggregate is considered as the most abundant and used secondary aggregate in concrete production, other types of solid waste are also being used in concrete for specific …
A comprehensive review on the use of recycled concrete aggregate …
Fig. 10 shows concrete containing natural coarse aggregate and recycled brick coarse aggregate (Liu et al., 2021). Hence, the RCA's physical, chemical, and mechanical characteristics must be investigated before use (Mills-Beale and You, 2010). As previously discussed, it is important to note that these properties would differ from the …
A review of recycled aggregate in concrete applications …
In Australia, recycled aggregate (both as coarse and as fine aggregate) has been the most common C&D waste used in concrete production. About 5.0 million …
A review of recycled aggregate in concrete applications …
The global aggregate production of 40 billion tons (Fig. 1) is an indication of the vast development projects which are materializing around the world [1].As the land for landfill becomes scarce and the world demand of aggregate reaches to an enormous 40 billion tons annually, ways to use C&D waste is gaining importance due to legislation, it …
Comparative Environmental Impacts of Recycled Concrete Aggregate …
Blengini et al. propose a management approach, i.e. sustainable aggregates resource management project (SARMa), which proposed guidelines for the sustainable management of aggregates.As per diversified studies conducted in recycling CDW, recycled concrete aggregate (RCA) can replace a significant portion of NA in the …
Environmental Evaluation of Concrete Containing Recycled …
This study aims to compare the potential environmental impact of the manufacture and production of recycled and by-product aggregates based on a life cycle assessment and to evaluate the environmental impact and cost when they are used as aggregates in concrete. To this end, the six potential environmental impacts (i.e., abiotic …
(PDF) Use of Recycled Concrete Aggregates in Production …
Recycled aggregate used to produce concrete differs from natural aggregate in t hat it contains old mortar attached to the surface of the aggregate. The RCA recycling process
Appraising the synergistic use of recycled asphalt pavement …
Appraising the synergistic use of recycled asphalt pavement and recycled concrete aggregate for the production of sustainable asphalt concrete. Author links open overlay panel Amjad Albayati a, Hasan Al ... (VA), recycled concrete aggregate (RCA), and reclaimed asphalt pavement aggregate (RAP). The VA is a crushed quartz …
A review of recycled aggregate in concrete applications …
The best estimates for 2015, of total aggregate production and recycled aggregate production of European Union countries including Ireland and the United Kingdom are depicted in Fig. 3 while Table 2 shows values for 6 years from 2010 to 2015. In European Union, the processing of construction waste (concrete, brick, asphalt and stone) into ...
Hybrid methods to improve microstructure of recycled …
Carbon-conditioning or chemical permeation methods can provide excellent microstructural improvements to recycled concrete and brick aggregate; however, the applications have their limitations. Further, recycled brick aggregate cannot be effectively carbon-conditioned with conventional methods as it contains only trace amounts of …
Carbon-conditioned recycled aggregate in concrete production …
This paper investigates the use of carbon-conditioned recycled aggregate (RA CO2) in concrete production.Experimental work is conducted for RA CO2 with varying chamber pressure (0 kPa, 75 kPa, 150 kPa), chamber duration (0 min, 30 min, 90 min) and RA CO2 replacement percentages (0%, 30%, ) for concrete production. Average …
Recycled Concrete as Aggregate for Structural Concrete Production
A comparative analysis of the experimental results of the properties of fresh and hardened concrete with different replacement ratios of natural with recycled coarse aggregate is presented in the paper. Recycled aggregate was made by crushing the waste concrete of laboratory test cubes and precast concrete columns. Three types of …
Recycled Concrete Aggregate
Reuse of recycled aggregate in the production of alkali-activated concrete. P. Chindaprasirt, T. Cao, in Handbook of Alkali-Activated Cements, Mortars and Concretes, 2015 19.2 A brief discussion on recycled aggregates. Recycled aggregate is defined as aggregate resulting from the processing of inorganic or mineral material previously used …
Alternative fine aggregates in production of sustainable …
Improvement of mechanical properties of recycled aggregate concrete basing on a new combination method between recycled aggregate and natural aggregate. Construct. ... Effects of foundry sand as a fine aggregate in concrete production. Construct. Build. Mater. (2014) M. Gesoglu et al. Failure characteristics of self …
Energy and CO2 from high performance recycled aggregate production
The production of recycled coarse aggregate implies generating large amounts of fines – a minimum fraction of 35–40%. As Fig. 2 shows, the generation of fines increases with a reduction in porosity of the recycled coarse aggregate, which is an increase in quality. Some recycling processes generate water absorptions around 1% …
Prediction of properties of recycled aggregate concrete …
Recycled aggregate concrete2.1. Recycled aggregate. Recycled aggregates include coarse recycled aggregates (CRA) with a typical particle size range of 4.75–31.5 mm and fine recycled aggregates (FRA) between 0.16 and 4.75 mm [27]. Since RA obtained from CDW contains hardened cement paste or mortar and the surface of …
Recycled Aggregates for Concrete Production: State-of-the …
The use of recycled aggregates for concrete production is regulated through the European existing standards, and it is limited to the coarse recycled …
Understanding the different types of recycled aggregates
Recycled Aggregate Types Recycled Type 1 (Sub-Base) Type 1 recycled aggregate is a type of recycled construction material that is produced from crushed concrete and sometimes includes other materials such as brick, asphalt, or rock. It is often used as a sub-base material for road construction, pathways, and hard-standing areas.
Recycled Aggregate: A Viable Solution for Sustainable …
Construction and demolition activities consume large amounts of natural resources, generating 4.5 bi tons of solid waste/year, called construction and demolition …
Recycled aggregates from construction and demolition …
Recycled aggregate is a sustainable solution for environmental depletion of construction sector. ... This article presents a literature review on the production and utilization of recycled aggregate in concrete. Because of its higher water absorption and lower density, the use of recycled aggregate can cause a slight reduction in workability ...
Use of recycled aggregate concrete in structural members: a …
Recycled aggregate production per unit weight of waste concrete. Download CSV Display Table. Concrete remains a significant component of mixed …
A review of life cycle assessment of recycled aggregate …
According to mass allocation, the environmental impact is weighted based on the mass ratio between the primary materials (waste disposal) and secondary materials (recycled aggregate production). However, there is a quality reduction between NAs and RAs, which is not considered in the approach of mass allocation. 5.1.6. Economic …
Environmental and Economic Comparison of Natural and Recycled …
Recycled aggregates (RAs) have been playing an important role in replacing natural aggregates (NAs) in concrete production, thereby contributing to a reduction in the extraction of natural resources and the promotion of a circular economy. However, it is important to assess the global impacts of this replacement, in both environmental and …
Life cycle assessment of natural and mixed recycled aggregate
The natural and mixed recycled aggregate production for use as road base and subbase have been compared through an attributional life cycle assessment.The primary data have been collected in a basalt natural aggregate production facility and in a recycling facility of mixed aggregate, both located in Southeast Brazil. The topic is …
Assessing Carbon Capture and Carbonation in Recycled …
Xing et al. showcased that recycled aggregate concrete exhibits the least environmental impact among the three concrete types with identical mix designs [52]. ... Accelerated carbonation of recycled concrete aggregates and its implications for the production of recycling concrete. Journal of Building Engineering, 79 (2023), Article …
Comparative environmental evaluation of aggregate production …
The figure shows that the production of fine aggregate from crushed stone has a single score environmental impact equivalent to 11.89 mPt (about 17% for extraction and handling, 23% for processing and 60% for transporting from extraction sites to the utilization sites), whereas 7.88 mPt is recorded from river sand (about 40% for extraction …
Recent advances in artificial aggregate production
A direct recycling of solid wastes as aggregate replacement is the primary option of prevalence, and among them the recycled concrete aggregate ... Cold bonding is a prevalent technology for aggregate production with the advantages of being energy saving and simple in terms of operation. However, the need of cementitious materials …
Electric Arc Furnace Slag as Coarse Recycled Aggregate for Concrete
Electric arc furnace (EAF) slag is a by-product of steel production in electric arc furnaces. Several studies have tried to demonstrate its suitability in civil engineering application, such as in bituminous mixtures and cement-based materials, due to its good physical, chemical and mineralogical properties. Particularly the re-use as coarse …
Recycled aggregates: Guidance for producers and …
aggregate production controls and testing procedures are the same so that the aggregate characteristics declared by different producers are directly ... A recycled aggregate having 55% concrete, 25% brick, 19% asphalt and ≤1% clay would have the categories Rc50, Rb30-, Ra20- and X1-.