In recycled aggregate concrete, the loss in mechanical strength and modulus of elasticity can be attributed, among other factors, to the presence of the mortar adhered to the recycled aggregate, resulting in higher water absorption and lower specific mass. ... The Duncan test grouped the 30RCC, 50RCC, and 70RCC specimens together, indicating a ...
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gates grouped by coarse and fine, natural and ... e 50% of recycled aggregate, f of recycled aggregate. Figure 4. GWP (kg CO 2 eq) vs. PE-NRe (MJ) results from the literature review, per ...
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Pre-saturating the recycled aggregate between 60 and 90 % of its 24h-water absorption is a recommendation [27, [35], ... the data were grouped in distinct categories of effective water to cement ratio, or weighted water absorption of aggregates to obtain the best coefficient of correlation (R 2). The procedure did not affect the physical and ...
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Polypropylene fibres and air entrainment have known freeze/thaw protection qualities when used in concrete (Richardson, 2003, Richardson and Wilkinson, 2009).Concrete manufactured using plain aggregate normally has a higher compressive strength when compared to concrete made with recycled demolition waste aggregate (Richardson et al., 2009).
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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 …
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Process of Recycling Concrete Aggregate. It is mainly done by two methods : 1. Mechanical Method. 2. Air-heating and Grinding Method. Uses of Recycled Concrete Aggregate. Recycled Concrete Aggregate has a wide variety of uses in the field of the construction Industry. The uses are grouped into two categories : Unprocessed Recycled Aggregate
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In recent years, the reuse of recycled concrete aggregate (RCA) in cementitious materials has garnered significant interest [6].Currently, natural aggregates dominate cement-based composites, comprising up to 60–75 % [7].However, the extensive expansion of global infrastructure projects has resulted in a depletion of natural aggregates, leaving civil …
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In this scenario, replacing NA with recycled aggregate (RA) from C&DW and other wastes can mitigate environmental problems. We review the use of RA for concrete production and draw the main challenges and outlook.
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Aggregates fall into three types based on where the minerals are sourced from: natural, manufactured, or recycled. Materials include sand, natural gravel, crushed rock, Type …
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105 grouped into one specimen series and tested after exposure to the ISO 834 standard fire for 0 106 min (i.e. at ambient temperature), 15 min, 30 min and 45 min. For each column specimen, the ... 113 The recycled aggregate concretes (R0, R35, R70) were produced from three types of …
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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, …
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For performance enhancement studies, cubes were cast keeping the recycled aggregate constant as 50% and varying copper slag in proportions of 0%, 25%, 50%, 75%, and with 3 cubes for each mix.
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Recycled Concrete Aggregate (RCA) To align with Singapore's vision in construction sustainability, Eastern Continent also recycle concrete debris from demolishing works and convert them into useable products as Recycled Concrete Aggregate (RCA). The primary process will be using excavator and jaw crusher to break up the concrete hardcore.
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7. Classification & properties of recycle aggregate concrete Material composition is the basis for classification of recycled concrete aggregate in two main types- 1) Crushed concrete 2) Mixed material Each of these types is divided in a class for bound and a class for unbound use Crushin g age Bulk specific gravity Bulk density Absorp tion (%) Crushin g value(% ) 1 days …
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Some pioneering studies were conducted on recycled aggregate concrete (RAC), Lu used substitution levels of 0, 25, 50, 75 ... and , and the air pressure P g (namely strain rate) were grouped into 0.3, 0.7, and 1.1 MPa. For each P g, each r, four repetitions of SHPB tests were carried out. 5 Results and Discussion. 5.1 Quasi-static ...
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In this scenario, replacing NA with recycled aggregate (RA) from C&DW and other wastes can mitigate environmental problems. We review the use of RA for concrete production and draw the main challenges and outlook. RA reduces concrete's fresh and hardened performance compared to NA, but these reductions are often negligible when the ...
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The above-mentioned experimental results were grouped according to the loading pattern during the triaxial test. ... The effect of the recycled aggregate source on the triaxial mechanical behavior of RAC was discussed in the previous Sections. Generally speaking, CDWs contain all kinds of building wastes, such as waste concrete lumps/blocks ...
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Coarse natural aggregates are normally grouped into gravel or crushed rock. The use of coarse CCA is permitted within BS 8500 and the section on Recycled Aggregates within 'How to design concrete structures to Eurocode 2: BS 8500 for building and civil structures' provides further details on this. Coarse RA is also permitted for use within ...
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Presentations were grouped into three sessions, this is the recording of session 2. Programme Overview. Session 2 - Exploring new uses. Introduction and welcome. Elaine Toogood, Director of Architecture and Sustainable Design, The Concrete Centre Current and evolving standards for use of recycled aggregate in concrete Mike will explain the ...
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It is assumed that the water absorbed into the aggregate (recycled or not) will not affect the effective water. For both recycled (RC) and mixed (MC) 20-mm concrete samples, a ... This means that the impact category indicator results are grouped to form damage categories. The environmental impact indicators 'global warming', 'ozone layer ...
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Previous research on recycled aggregate concrete-filled steel tube (RACFST) members was briefly summarised herein. ... S100-R35 and S100-R70), with the four column specimens, fabricated from the same type of concrete, grouped into one specimen series and tested after exposure to the ISO 834 standard fire for 0 min (i.e. at ambient temperature ...
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Use of recycled aggregate in concrete application: case studies. Sustainable waste management and recycling: construction demolition waste. In: International Conference, Concrete and Masonry Research Group, Kingston University; September 14–15 2004. p. 245–57. Google Scholar [4] C. Poon, D. Chan. The use of recycled aggregate in concrete in ...
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This study introduces an innovative approach to enhancing recycled aggregate concrete (RAC) by incorporating nanosilica (NS) and natural fibers (NF), specifically sisal fiber (SF) and palm fiber (PF). This novel combination aims to overcome the inherent limitations of RAC, such as reduced strength and durability, while promoting sustainability ...
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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% at the expense ...
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Geopolymer recycled aggregate concrete (GRAC) is a new green construction material, which uses geopolymer as the binder and recycled concrete as aggregates. To compare the flexural performance of GRAC and ordinary recycled aggregate concrete (RAC) beams, static loading tests were conducted on seven GRAC beams and three RAC beams.
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4.2.2.1 Recycled concrete coarse aggregate Recycled aggregate exhibits a notable increase in water absorption, neces- sitating additional water during production. T absh and …
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Inert, construction and demolition waste (and especially crushed concrete) forms a possible source for recycled aggregates when produced in accordance with a WRAP Quality …
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Regarding the creation of recycled aggregate, which consists of natural aggregate and old mortar, the process begins with the previously generated natural aggregate (referred to as A in Fig. 6 (a)). ... Clustering process for skeleton junctions: while there is a skeleton junction not grouped into a cluster do Set the origin as a centroid.
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On this access road project, the combination of Tensar InterAx geogrid and recycled aggregate achieved a 32% reduction in construction cost, a 1.2 day reduction in construction time, along …
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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 economic terms. …
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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 in construction (BS EN 12620, 2013; MPA, 2013).When consisting mainly of crushed concrete, it may be classified as recycled concrete aggregate (RCA). Information on processing old concrete into RCA can …
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Sources for these basic materials can be grouped into three main areas: Mining of mineral aggregate deposits, including sand, gravel, and stone; use of waste slag from the manufacture of iron and steel; ... Further tests and studies on the recycled aggregate concrete are highly recommended to indicate the different characteristics of recycled ...
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The primary disadvantages of recycled aggregate lie in the residual old cement mortar adhered to its surface and the micro-cracks and damage incurred during its production [26, 27]. These defects result in recycled aggregate having higher porosity and water absorption, increasing the heterogeneity of the internal structure [28, 29].
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There are several types of recycled aggregates, including gravel, sand, crushed stone, asphalt, bricks and blocks, slags and recycled concrete. Recycled aggregate concrete (RAC) is also …
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Therefore, the qualities of recycled aggregate needs to be further improved. In this study, waste concrete was divided into waste sand (0.3–4.75 mm) and waste powder (<0.3 mm), and it is proposed that the waste sand was strengthened as the inner core. In addition, the waste powder, microbial solution and binding material as the outer core.
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The present paper gives a brief status of recycled aggregate concrete made out of recycled aggregate, summarizes and critically analyses some of the most important research findings over the past few years regarding the material aspects. ... These approaches can be grouped in to three broad aspects which have been explained in details as ...
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The recycled concrete aggregate is carefully crushed, sorted, and tested to ensure it meets quality and safety standards, making it a reliable material for both large-scale infrastructure projects and smaller residential uses. Trap Rock Industries' dedication to concrete recycling reflects its role as an industry leader in sustainable building ...
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