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This article presents a comprehensive review on the use of recycled concrete aggregate (RCA) and recycled aggregate concrete (RAC) in construction, with emphasis on structural applications and identification of …
The physical and mechanical properties of these aggregates, and their strength and performance of recycled aggregate concrete are determined. The results show that treatment with H 2 SO 4, and heating and scrubbing yield, aggregate with reduced water absorption and other desired properties of natural aggregate. The concrete made out of these ...
To reduce the shrinkage and explore the best content of mineral admixtures of coarse aggregate ultra-high performance concrete (CA-UHPC), this study conducted 12 …
Utilizing alternate aggregates is crucial for conserving resources, promoting sustainability, and managing waste effectively. The focus of the current study was the …
By collecting the used concrete and breaking it up, recycled concrete aggregate (RCA) is created (Fig. 1). This paper focuses on coarse RCA which is the coarse aggregate …
The raw materials for GPC primarily include cementitious materials made from industrial by-products and natural materials. Currently, the most commonly used materials for …
The mechanical properties of recycled brick aggregate concrete (RBAC) are significantly affected by design parameters such as recycled brick aggregate (RBA) replacement ratio and water-cement ratio, which not only increases the difficulty of designing RBAC by experimental or theoretical methods, but also makes the mechanical properties (compressive …
Reusing aggregate from building and demolition waste can help protect the ordinary natural aggregate supply, reduce landfill demand, and drive toward a more …
In Japan, recycled concrete aggregate (RCA) and recycled-aggregate concrete (RAC) are standardized in the Japanese Industrial Standards (JIS) A 5021–5023. The differences between the specifications in JIS and those in foreign countries are explained. In Japan, the durability of RAC under severe conditions, particularly freezing and thawing with/without …
Improving the performance of recycled brick aggregates to enhance concrete performance is the key to promoting recycled concrete technology. In this paper, pure bacteria (Bacillus subtilis) and unoptimized activated sludge mixed bacteria are used to reinforce recycled brick aggregates by soaking them, and a multi-faceted assessment evaluation of microbial …
Abstract. This paper focuses on the particle crushing mechanism of construction solid waste recycled aggregate (CWRA), particularly recycled concrete (RC) and recycled bricks (RB), using natural gravel (NG) as a control group.
This paper presents the results of an investigation into the bonding characteristics between complete carbonation recycled aggregate concrete (RAC) and reinforcing steel. Test specimens were meticulously prepared, incorporating five distinct replacement ratios (0%, 30%, 50%, 70%, and ) of recycled coarse aggregate (RCA).
Recently, studies on multiple recycling of concrete have been attracting attention. In general, multiple recycling increases adhered mortar content of aggregate, consequently, the water absorption of the multiple recycled aggregate is increased, and the slump of concrete with the multiple recycled aggregate is reduced. Therefore, this study attempted to offset the …
The recycling of locally collected concrete waste is being promoted toward reducing the carbon footprint. In the preparation of concrete, recycled concrete aggregates (RCA) are encouraged instead of natural aggregates (NA), as they can help reduce the consumption of materials, the extraction and transportation of which can be costly and …
Previous research indicates that lightweight aggregate (LWA) concrete exhibits more brittle failure under compression than conventional normal density (ND) concrete. In contrast, angle-ply fiber-reinforced polymer (FRP) filament-wound tubes filled with ND concrete show significant improvements in strength and deformability compared to hollow tubes.
This study experimentally investigated the behavior of reinforced recycled aggregate concrete (RAC) beams under monotonic and cyclic loadings to identify the advantages and shortcomings of RAC in reinforced concrete beams. Five RAC specimens and one normal aggregate concrete (NAC) specimen were tested to failure. The concrete …
Journal Suggester; Open access publishing; We're here to help. Find guidance on Author Services. Home All Journals ... Aggregate-to-cement ratio (3, 4 and 5), compaction (0, 30 and 60 blows from standard Proctor rammer), aggregate sizes (5–12 mm, 12–18 mm and 18–25 mm) and aggregate shape (0, 200 and 1000 revolutions of milling in Los ...
International Journal of Environmental Design & Construction Management Published by Cambridge Research and Publications IJECM ISSN-2325-1884(Print) 306 Vol. 21 No. 4 ... blending aggregate for concrete used for highway pavement and its effect on compressive strength of concrete. Keywords: Concrete, aggregate, ...
The new aggregate is similar to conventional lightweight aggregates, but the ratio of density of concrete to compressive strength is much more favorable to making structural concrete. This paper summarizes the results of experiments on the mechanical properties of concrete made of this new expanded glass aggregate.
The chemical and physical interactions in the interfacial transition zone (ITZ) between three different types of coarse aggregates (limestone, granite and basalt) and cement paste were investigated. The results show that all the aggregates are chemically active. Significant amounts of Ca2+, K+, and Na+ are absorbed by all the aggregates from the …
Pervious concrete (PC) as a green infrastructure material has been increasingly used due to its positive environmental impacts, such as controlling storm water runoff, removing water pollutants and reducing heat island effect. The aggregate gradation is a critical factor influencing the physical properties of PC. Therefore, this paper represents an attempt to …
To alleviate the shortage of river sand and the pollution of construction waste, this paper proposed the recycled aggregate concrete (RAC) and its application in structures. Two specimens at 1:2 scale are tested under quasi-static cyclic load, and the results were verified by the finite element model (FEM). The specimen KJ-1 is a frame structure composed of the steel …
AbstractThe suitability of crushed concrete or recycled concrete aggregate (RCA) materials has been evaluated for use as pavement material for unbound basecourses. This paper covers the general engineering properties and response to cyclic loading as ...
Recycled aggregate concrete (RAC) is a sustainable alternative that encounters challenges due to varying sources and processing methods. This study introduces a novel approach to optimize the mix proportions of RAC through machine learning and multi-objective optimization techniques. ... IEEE/CAA Journal of Automatica Sinica, 8 (10) (2021), pp ...
Turning construction and demolition wastes (CDW) into recycled fine/coarse aggregate to prepare recycled aggregate concrete (RAC) has been widely considered as an …
On probability distribution of chloride diffusion coefficient for recycled aggregate concrete. International Journal of Concrete Structures and Materials, 10(1), 61–73. Article Google Scholar Yu, Y., Yu, J., & Ge, Y. (2016). Water and chloride permeability research on ordinary cement mortar and concrete with compound admixture and fly ash.
There is evidence that the presence of certain microfine coatings (⩽ 75 μ m) on coarse aggregates encountered in actual field conditions and accepted for state projects has adverse consequences for the properties of hardened concrete. The purpose of this research was to investigate the influence of natural coarse aggregate coatings on physical properties of …
Waste concrete with a particle size of 2.36–19 mm after crushing can be called RA. The RA formed by simple treatment of waste concrete usually contains many initial defects, such as a large amount of adhesive mortar and microcracks [14, 15].These adhesive mortars are rough and porous, resulting in greater water absorption compared to NA and the formation of a larger …
Abstract: Fine aggregate has been extensively used in the construction industry as a key component of concrete production. Although river sand is one of the major sources of fine aggregate, different sources exhibit different properties by virtue of the geological formation of the drainage basin. Further, the
International Journal of Concrete Technology(IJCT) is an international peer-reviewed journal that covers topics related to advancement in concrete technology starting from concrete plants, concrete mixer to reinforced concretes. The Journal publishes both experimental as well as theoretical articles and review papers that can create an impact in the research community.
recycled aggregate produced only 0.0024 million ton carbon is produced. Considering the global consumption of 10 billion tons/year of aggregate for concrete production, the carbon footprint can be determined for the natural aggregate as well as for the recycled aggregate. The use of recycled aggregate generally increases
AbstractThe influence of recycled coarse aggregates (RCAs) on the fresh, hardened, and freeze-thaw durability properties of recycled aggregate concrete (RAC) is investigated in the research reported in this paper. Four different mixes were considered with ...
Recycled concrete is a green material composed of natural aggregate and recycled aggregate mixed with cementing material and water in a certain ratio. The random distribution of aggregate in concrete has a great impact on material properties due to its supporting effect. In order to explore the characteristics of aggregate and the influence of its …
This article presents a comprehensive and critical review of the structural performances of reinforced recycled aggregate concrete beams and columns based on …
Abstract This study investigates the bond behavior of glass aggregate–reinforced concrete (GARC) after freeze–thaw cycles, considering a number of freeze–thaw cycles (10, 20, and 30) and fine aggregate replacement rates (25%, 50%, and 75%) as variable ... Practical Applications Glass aggregate–reinforced concrete has excellent resistance to freeze–thaw …
Amidst the global pursuit of sustainable alternatives in concrete production, this study explores the viability of incorporating by-products or waste materials as aggregates to support the concrete construction industry, with a specific emphasis on steel slag. The objective of this study is to evaluate the effectiveness of steel slag as a partial replacement for fine and …
Recycled aggregate concrete exhibits considerably complicated structure than natural aggregate concrete (NAC) as it contains dual interfacial transition zones (ITZ) between old mortar and aggregate and new mortar and old mortar which increases the porosity and causes the reduction in strength (Liu et al., 2011).
Concrete is the most widely used construction material. Cement, which is the binder in concrete, is produced in increasing quantities each year and the total production of cement around the world is estimated approximately 5 billion tons [].Manufacture of Portland cement is the third most energy-intensive production process and production of 1 ton of …
Journal of Building Engineering. Volume 38, June 2021, 102196. ... It is also reported that multiple crushed concrete aggregate, will eventually have increase of the volume of old adhered mortar [11]. In Japan, with repeated crushing, more …
Journal of Building Engineering. Volume 43, November 2021, 102567. Use of ceramic wastes as aggregates in concrete production: A review ... (FBCA) content at each curing age. The 28-day compressive strength of ceramic aggregate concrete, with a 20– replacement ratio, varied in the range of 40–47 MPa, 33–38 MPa, and 29–35 MPa for the ...