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Crushing value is to evaluate the ability to resist crushing. The smaller the value is, the stronger the crushing capacity is. Compared with the original aggregate, the crushing values of RA treated by C-3, C-7, N-P, and H method were reduced by 11.5%, 7.6%, 3.3%, and 6.9%, respectively.
In the present investigation, an attempt was made to study the influence of the strength of parent concrete on the properties of recycled aggregates and recycled aggregate concrete. In this study, four grades of normal concrete mixes: M20, M25, M30, and M40 were considered as parent concrete to produce the recycled coarse …
The crushing strength of recycled aggregate materials for three samples prepared for the overall performance determination was relatively similar to the conventional aggregate materials that occurred naturally "Sehgal et al. [13]. This is in the acceptable values for application in various parts of the ongoing projects.
Construction and Demolition Waste (C&DW) is generated around the world and its quantity will increase in the future. Recycling has become the favored method of dealing with concrete waste but, to avoid its downcycling, it is important to develop a recycling process which is able to produce high-grade recycled concrete aggregates …
Geopolymer recycled aggregate concrete (GPRAC) is a new type of green material with broad application prospects by replacing ordinary Portland cement with geopolymer and natural aggregates with recycled aggregates. This paper summarizes the research about the mechanical properties, durability, and microscopic aspects of …
Ceramic aggregate has the characteristics of light weight, heat insulation, and low cost, and recycled aggregate is a type of green material that realizes the re-crushing of construction waste. This paper studied the impact of replacing natural coarse aggregate with ceramic aggregate and natural sand with recycled fine aggregate, on the physical, …
An enormous amount of construction and demolition waste is generated globally every year, and it increases disposal costs in landfills. The advantage of adopting crushed concrete aggregate as an alternative cushioning material provides a novel approach for reusing and recycling waste materials. However, a lack of understanding of …
This research aims to analyse the variables that influence the self-cementing of recycled aggregates, both concrete and mixed. Elaborating recycled …
Furthermore, during the crushing process, the forced crushing method will produce some microcracks on the surface or inside recycled coarse aggregates (Figure 5e,f). These will have adverse effects on the strength of recycled concrete.
According to the analysis results of the nonlinear fitting curves between the property indexes of mixed recycled coarse aggregate (water absorption and crushing value) and the performance parameters of mixed recycled coarse aggregate concretes (cubic compressive strength, prism compressive strength, splitting tensile strength, …
From the table, it is observed that the aggregate crushing value of natural coarse aggregate is 17.52% against 33.5, 34.4, and 36.7%, respectively, for recycled …
The mechanism behind this mechanochemical and thermal treatment is that high-quality RCAs were obtained; these were characterized by a low absorption ratio, a …
However, the traditional recycled aggregates prepared by crushing and screening processes are mainly composed of broken brick and concrete aggregate, which have some problems, ... A California Bearing Ratio tester was used to determine the crushing strength value of the prepared artificial aggregates. Before the test, a Vernier …
A total number of 11 papers were considered for the analysis of tensile and flexural strength of concrete containing recycled aggregates . Referring to the tensile strength, recycled aggregates with less attached mortar can be used as a substitute of natural aggregate, producing a concrete with a similar or even better performance .
Recycled aggregates. Said Kenai, in Waste and Supplementary Cementitious Materials in Concrete, 2018. Abstract. Construction industry generates huge amounts of debris that needs to be recycled and reused as recycled aggregates (RAs) for partial or total substitution of natural aggregates. Recycling reduces waste and reduces energy …
Distribution of specific density, saturated surface dry density, water absorption, and crushing value of mixed recycled coarse aggregate, as well as the …
2.1. Test details. The test includes three parts: in the first part, the physical properties of coarse aggregate are taken as the research object, the effective water absorption, apparent density and crushing index of coarse aggregate are taken as variables; in the second part, the compressive strength of cement mortar is taken as the …
Recycled aggregate comes primarily from PCC and AC from road rehabilitation and maintenance, demolition, and leftover batches of AC and PCC. After processing, the rocks retain bits of cement or asphalt. A roadway is built in several layers: pavement, base, and sometimes subbase. The pavement is the surface layer, and is made of PCC or AC.
The aggregate crushing value is an essential index in the construction of road bases and is defined as the mass percentage of fine particles after a confined compression test of recycled CDW. In this study, experiments and numerical simulations were conducted to evaluate the crushing characteristics of the CDW, consisting of three …
Among them, the studies of Ref. [14] evaluated the use of RA obtained by crushing RMC waste that was deposited without adequate treatment and concluded that for the lowest strength level (17 MPa), the replacement of up to 50% of the aggregate provides concrete with an average compressive strength only 10% lower than that of conventional …
The recycled aggregate concrete (RAC) is widely applied in existing engineering, due to the great economy and environmental protection. However, there are several disadvantages of RAC: complex existing mix design methods, lower strength, and brittleness. This chapter initially presents a simple mixed design method.
The strengthening of recycled aggregates is a critical issue, as the low strength of recycled aggregates is the main reason that limits their widespread use. The slurry coating method can strengthen the recycled aggregates by repairing the aggregate surface, but it is hard to improve the internal strength due to the existence of pores and …
where σ 0 is the characteristic crushing strength, m is the Weibull modulus, d is the median particle size for each particle group, and λ is a fitting parameter with a …
Abstract This study proposes a new mix design method for C30 recycled concrete using recycled aggregate crushed from different strength source concrete (SC). The dosages of cement, water, sand, and coarse recycled concrete aggregate (CRCA) are the same as the corresponding components in natural concrete, but the CRCA should be …
Aggregate crushing test. The strength of the aggregate can be assessed by conducting this test. The aggregate crushing value gives a relative measure of the resistance of an aggregate to crushing under a gradually applied compressive load. Size of recycled aggregates taken for conducting test was between 12.5mm and 10mm.
In addition, water absorption refers to the amount of water absorbed by aggregate voids, and the results are illustrated in Fig. 4. While, crushing value gives a relative measure of the crushing resistance of the aggregate under the gradually applied compressive load, and the results are. Conclusions
In this study, recycled aggregates (RA) from crushed clay bricks were used to make recycled aggregates pervious concrete (RAPC), and the influence of crushing index on its properties were presented. Based on the findings of this summary, the following items may be drawn as following. The value of compressive strength, flexural strength …
Reading time: 5 minutes. The aggregates used in the production of concrete are inert granular materials such as gravel, crushed stone, sand, slag, recycled concrete, and geosynthetic aggregates. The aggregates may be natural, manufactured, or recycled. Fig 1: Aggregates used in production of concrete. The aggregates are broadly classified into …
Maximum crushing strength of recycled ceramic brick aggregate used by Cachim [ 10 ] was 30 MPa, though the age of the parent structure was not mentioned. Figure 2.
The application of recycled coarse aggregates (RCA) in high-performance concrete (HPC) was analyzed in the article. In the paper, the behavior of HPC with coarse recycled aggregate and natural coarse aggregate (NCA) was compared. Short-term experiments were conducted, including concrete deformation, deflection, load bearing …
crushing value is defined by the percentage loss in mass on 2.36 mm size of test. Bigger percentage of aggregate crushing value means the aggregate is inferior in quality. According to BS 882:1992, aggregate with crushing value less than 25% can be used in heavy duty floor, crushing value for more than 30%, aggregate to be used in concrete for
where A max is the mass of accumulated pollutants, mg; C i is the concentration of pollutants in the ith diffusion solution, mg/L; V L, i is the volume of the diffusion solution, L.. Results Crushing Characteristics …
aggregate pellets (with lightweight and possessing less specific gravity and high impact value than gravel) were batch manufactured by a cold bonded technique using disc pelletiser (used to perform agglomeration). The prepared aggregates are characterised based on their crushing and impact strength rate and also moisture absorption.
This pore structure also interferes with the mechanical strength of the aggregate itself. Regarding its resistance from crushing and degradation, recycled aggregate has a higher aggregate crushing value, higher Los Angeles abrasion index, and lower "10% fine" value [32, 46, 47, 62].
This study evaluates the quality and mechanical performance of various shapes of reclaimed concrete aggregates (RCAs), including elongated, cone-shaped, …
The strength and deformation of cemented recycled aggregates was studied using DEM (Mohammadinia et al., ... A DEM numerical simulation can be used to predict the crushing value of the recycled aggregates. The crushing value is obtained from the experiments, while the bond breakage ratio is determined from the DEM simulations. In …
Recycled aggregates consist mainly of crushed concrete and crushed asphalt pavement. Construction aggregates make up more than 80 percent of the total aggregates market, …
