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AbstractThe present study illustrates the susceptibility of optimized-quality recycled concrete aggregate (RCA) to supplementary cementitious materials (SCMs), …
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In addition, methods for enhancing the mechanical characteristics of recycled aggregate and long-term efficiency such as improving the properties without …
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Recycled concrete aggregate (RCA) has been widely used as a resource in reinforced soil structures, especially as a substitute for natural aggregate. Direct shear tests were conducted using a dynamic direct shear apparatus to study the effects of particle-size gradation (0.06–37.5 mm) on the shear properties of RCA-geogrid interface, in which ...
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As shown in Table 1, three types of recycled aggregate concrete were prepared, with water binder ratio (w/b) of 0.48, sand ratio of 37%, and recycled aggregate content of ."M1" refers to ordinary recycled aggregate concrete; "M2" refers to recycled aggregate concrete prepared with 15% fly ash equivalent instead of cement; …
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1. Introduction. Significant construction and demolition wastes due to economic and construction development are generated constantly worldwide, particularly in developing countries, such as India and China [1].In view of the considerable demand for natural aggregates in construction and for enhanced sustainability, waste concrete must …
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At present, compared with other recycled coarse aggregate types, recycled concrete aggregate is the most extensive implemented RA in construction, and organizations in many countries have developed specifications [10], [11], [12]. In this paper, the performance and application of recycled concrete aggregate were focused on.
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This study investigates the influence of recycled fine aggregates (RFA) and waste concrete powder (WCP) on the compressive strength of concrete. The response surface methodology is employed, considering three factors: the content of WCP, the water–cement ratio, and the replacement ratio of recycled fine aggregates. …
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RAC is processed from solid construction waste. Particles with particle sizes between 75 µm and 4.75 mm are called recycled fine aggregate, while those with particle sizes greater than 4.75 mm are called recycled coarse aggregate [31]pared with natural aggregate, RCCA is coated with a large amount of old mortar, which generally …
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Abstract and Figures. This study aims to examine the impact of using basalt macro-fibers (BMF) on characteristics of concrete made with recycled concrete aggregates (RCA). Test variables included ...
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The development of stress–strain characteristics of natural aggregate concrete with partial replacement of sand with waste foundry sand and addition of superplasticizer demonstrated in Fig. ... Hansen TC (1986) Recycled aggregate and recycled aggregate concrete, second state-of-the-art report, developments from …
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Aggregate strength, gradation, absorption, specific gravity, shape and texture are some of the physical and mechanical characteristics that contribute to the …
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Recycled aggregate (RA) made from waste concrete is an environmentally friendly alternative to natural aggregate (NA) for concrete manufacturing. However, compared to NA concrete, concrete produced with recycled aggregates has poor characteristics. ... Hanumesh et al., 2018 [51] utilized PPFs in RAC and noticed …
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This study points out the close relationship between several quality indicators of recycled aggregate and the performance of recycled aggregate concrete. Regarding the diversity in quality and composition of the recycled concrete products, three laboratory produced air-entrained-concretes with low, medium and high water-cement ratios and a …
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Due to the complication of sources and types of CDW, there are great differences in properties among recycled coarse aggregates [6, 7].Most of the demolished buildings in Chinese cities are brick-concrete structures built in the 1960s–1980s, and such recycled aggregates are mainly composed of crushed brick aggregate and crushed …
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Replacing natural aggregate with construction waste to prepare concrete is an effective way of its resource utilization, which is in line with China 's " carbon peaking and carbon neutrality " strategy and the green development needs of the construction industry.Due to the existing technology is difficult to completely separate waste bricks …
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The recycled aggregate negatively influenced the compressive strength, which curtailed with an escalation in the quantity of recycled aggregate. (Arulrajah et al., 2016) FA: ... The optimum replacement level is governed by different factors such as the characteristics of the recycled aggregates, the level of workability adopted during the ...
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This study was conducted with the aim to chemically remove the cement paste attached to the aggregate surface using acidic substances. Sulfuric and hydrochloric acids were used as the acidic substances, and after analyzing the quality characteristics of the aggregates following the acid treatment, a mortar test was performed using the …
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In this study, the comprehensive performance and material properties of recycled aggregate concrete (RAC) under the coupled effect of salt-frost cycles were investigated to simulate the effect of complex environmental effects on the durability and deterioration of RAC. The tests on mass loss, relative dynamic modulus of elasticity (RDME), and …
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The study showed that the recycled aggregates can be used in rigid pavements also and the inclusion of fibers can benefit the fatigue performance of recycled aggregate concrete. Discover the world ...
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Sources of recycled aggregate for Recycled Aggregate Concrete (RAC) Pexels. When a structure is demolished, the particles are of larger sizes. So to make the processing easier the particles need to be crushed down to 300mm. Steps included in recycling aggregates Separation. 75% of the concrete is made of aggregates.
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The recycled coarse aggregate (RCA) and recycled fine aggregate (RFA) complicate the interfacial transition zone (ITZ) and pore structure of RAC [21], [22]. Wu et al. [23] indicated that the fracture energy and fracture toughness of recycled coarse aggregate concrete (RCAC) decreased with the increase of RCA replacement rate.
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The inherent inferior quality of recycled coarse aggregate (RCA) influences the microstructural characteristics and consequently, the macro-mechanical properties of recycled aggregate concrete (RAC). The present paper investigates the influence of aggregate properties, degree of hydration ( α ), and micro and meso level …
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Abstract. Recycled aggregate (RA) is a product of construction and demolition wastes, and RA particle presents low strength and adhesion with asphalt mortar compared with natural aggregate. With the aim of studying fracture characteristics of recycled aggregate asphalt concrete (RAAC), the influence of RA on interfacial zone …
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AbstractWith the rise in the adoption of recycled aggregate for construction, investigation on ways to improve its quality has been wide spread. The major factor that affects the quality of recycled aggregate is the large amount of cement mortar that remains on the surface of the recycled aggregate. This attached mortar results in …
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Properties of recycled aggregate concrete (RAC) are influenced by the composition and particle size distribution of recycled coarse aggregate (RCA). The study herein designed seven distinct groups of RACs with varying aggregate fractal dimensions (D) and one group of natural concrete (NAC). The impact of D on the workability, …
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Characteristic of recycled aggregate. Crushing hardened concrete is a lot like crushing natural rock, and the grade or quality of the original concrete doesn't make a big difference [5]. You can expect recycled concrete aggregate made from all but the worst original concrete to pass the same tests that are done on regular aggregates [4].
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Three types of crushing tests were carried out to investigate the crushing characteristics of the recycled aggregate particles, (i) single-particle crushing, (ii) multi-particle crushing, and (iii) the aggregate crushing value test. The experimental setups are shown in Fig. 1 (a). Universal electronic material testing machines with various ...
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The viscous property of the recycled concrete aggregate is similar to the one of ordinary type backfill materials. When well compacted around and pre-peak stiffness decreases at a very high rate. The viscous property of the recycled concrete aggregate is similar to the one of ordinary type backfill materials.
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First, the aggregate fragmentation caused by compaction effort was simulated using the superpave gyratory compactor. In this regard, the influences of aggregate type and RA content were investigated. Second, the indoor experiment scheme was determined using the Taguchi method to obtain compaction data of recycled …
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