Use Of Recycled Aggregate In Concrete – IJERT
The specific gravity in saturated surface dry condition of recycled concrete aggregate was found from 2.35 to 2.58 which are less but satisfying the results. If specific gravity is less than 2.4, it may cause segregation, honeycombing & also yield of concrete may get reduced. ... The bulk density of recycled aggregate is lower than that of ...
Materials | Free Full-Text | Influence of Wetting and Drying
Recently, concerns have been rising about the impact of increasing the depletion of natural resources and the relevant generation of construction and demolition waste, on the environment and economy. Therefore, several efforts have been made to promote sustainable efficiency in the construction industry and the use of recycled …
Properties of HPC with recycled aggregates
Dry-loose density. As aforementioned, recycled aggregates have lower specific gravity than that of natural aggregates and consequently the dry-loose density of recycled aggregates is lighter than natural aggregates in the range of 1350 kg/m 3 (Table 1). 3.1.4. Soundness and wear resistance
Thermal Performance of Concrete with Recycled Concrete …
The joint use of GRC+MRA, in turn, induced declines in dry density relative to NAC of 10.4% in R10/50 and 13.1% in R25/50, findings consistent with earlier observations in concrete made with recycled (coarse and fine) aggregate consisting of crushed waste clay brick .
Drying shrinkage of geopolymeric recycled aggregate …
Table 2 reports the physical and mechanical properties of natural and recycled coarse aggregates. The density, absorption, and crushing value were tested according to the Standard for Technical Requirements and Test Method of Sand and Crushed Stone (or Gravel) for Ordinary Concrete (JGJ52-2019). The content of residual …
Recycled Concrete Aggregate Classification Based on …
German standard DIN-4226–100 limits maximum water absorption to 10%, and oven-dry density should exceed 2000 kg/m 3 for high-quality RCA in structural concrete. Water …
Specific gravity and dry-rooded bulk density of aggregates
Table 1 presents aggregate size distribution of different aggregate types used for construction. Fig. 3 compares the dry-rodded bulk density with the specific gravity of different limestone and ...
Bulk density of recycled aggregates | Download Scientific …
The compressive strength of mixes contained recycled concrete aggregate (RCA) at age of 7, 28 and 56 day were less than natural aggregate concrete, except concrete mixes with 20% and 40% coarse ...
Micro- and macro-porosity of dry- and saturated-state recycled …
Both the RDSAC's and RDAC's density decrease with the incorporation of recycled saturated aggregate (RSA) and recycled dry aggregate (RDA), because on the one hand of the lower density of recycled aggregate and, on the other, of the mortar differences induced by the aggregate production and mixing method. The influence of …
(PDF) A Study on Properties of Recycled Coarse …
The recycled aggregate was used as 0%, 20%, 50% and replacements of coarse natural aggregate. Furthermore, fly ash was employed as 0% and 25% addition of cement.
Assessment of the engineering properties and economic
The dry density of the recycled aggregate concrete developed using the RBA and coconut shell aggregate was less than 2000 kg/m 3, thereby satisfying the requirements of LWC. In addition, the UPV of the recycled aggregate concrete showed a good linear correlation with its dry density, indicating that the recycled aggregate was …
Recycled Aggregates
Only up to 10 to 20 percent fine RCA is beneficial. The aggregate should be tested at several substitution rates to determine the optimal rate. Often recycled aggregate is combined with aggregate when used in new concrete. An example of a mix design using recycled aggregates in a pavement application is shown following table.
Sustainable Materials: A Review of Recycled Concrete Aggregate …
Surface image of natural and recycled concrete aggregates (a, c, e: Recycled concrete aggregate; b, d, f: Natural aggregate) (64-66). Figures - uploaded by Ali Mardani Author content
Recycled aggregates from construction and …
The acceptable content of recycled aggregates in concrete depends on the desired concrete strength grade and the characteristics of the recycled aggregate, …
Study on the Effect of Recycled Fine Aggregate Qualities on …
One promising solution lies in the utilization of recycled fine aggregate (RFA), especially in combination with the emerging geopolymer technology, an innovative alternative to traditional cement. ... Absolute dry density refers to the mass of sand per unit volume in a completely dry state; that is, without any moisture. On the other hand ...
A REVIEW OF RECYCLED CONCRETE AGGREGATES AS A
recycled aggregates, which were cured at 20 C in a water bath [8]. However, with of RCA there was a reduction in by 20-25% as compared to NA, at 28 days. with the same effective w /c of 0.5 ...
Micro- and macro-porosity of dry- and saturated-state recycled …
The results show that the dry and saturated recycled aggregate lead to very different concrete properties. On the one hand, the use of dry aggregate causes a local reduction of the w/c ratio ...
Density of Aggregate
The relative density (specific gravity) of an aggregate is the ratio of its mass to the mass of an equal volume of water. Relative Density = Mass of the Aggregate / Mass of equal volume of water. Key Features: Most aggregates have a relative density between 2.4-2.9 with a corresponding particle (mass) density of 2400-2900 kg/m3 (150-181 lb/ft3).
Characterization of compaction and CBR properties …
As can be seen in the figure, the maximum dry density (MDD) was observed close to zero void curves (ZVC) for both tested samples of D max = 25 and …
Mechanical Properties, Dry Shrinkage, and Water …
The recycled concrete aggregate (RCA) ... (OMC) and maximum dry density (MDD) of the samples can be derived by the curves. As can be seen, the OMCs of U0, U4, U8, and U12 are 8.7, 9.8, 10.4, and 11.5%, respectively. The OMC increases with higher ultrafine RCA percentages. This is attributed to the high water absorption of …
A Study on the Properties of Recycled Aggregate …
Technology is needed to resolve the quality decline, due to impurities, by processing the waste materials, implementing technology to remove mortar from the surface of the recycled fine aggregate, and …
Buildings | Free Full-Text | The Effect of Phase Change
A closer examination of the data in Table 1 reveals that this discrepancy can be attributed to the inherently higher dry density of the gravel in comparison to the recycled aggregate (RA). The variations in dry density observed among the mixtures reflect the distinct characteristics of the aggregate components used in their formulations.
Strength and Durability Evaluation of Recycled Aggregate …
This paper discusses the suitability of producing concrete with 100 % recycled aggregate to meet durability and strength requirements for different applications. Aggregate strength, gradation, absorption, specific gravity, shape and texture are some of the physical and mechanical characteristics that contribute to the strength and durability …
Recycled aggregates from construction and demolition
Usually, the international standards restrict the use of recycled aggregates in structural concretes. The acceptable content of recycled aggregates in concrete depends on the desired concrete strength grade and the characteristics of the recycled aggregate, such as composition, dry density, water absorption, and the percentage of …
Recycled Ceramic Fine Aggregate for Masonry Mortar Production …
The particle density of recycled fine aggregate is 2.38 k/cm 3. Penteado et al. reported similar results using samples of three ... with an increase in the replacement percentage when using recycled fine aggregate from ceramic walls because the dry density of recycled fine aggregate was lower than that of the natural fine aggregate …
Effect of different substitution of natural aggregate by recycled …
It was noticed that using of recycled aggregate decreased the dry density of pervious concrete and a systematical decreasing in dry density was observed when the natural aggregate replaced with the recycled aggregate at designated levels. The decreasing rate of 8.5 and 10.2 % in dry density were observed when the recycled …
Quality improvement of recycled fine aggregate using steel …
The recycled aggregates were of high quality, evidenced by the fact that the oven-dry density and absorption ratio measured after the abrasion using sulfuric acid solution were 2.51 g/cm 3 and 2.3%, respectively, which satisfied the oven-dry density and absorption ratio criteria for Class I concrete, which are "over 2.2 g/cm 3 " and ...
Concrete Mix Design for Completely Recycled …
The porosity of the adhered mortar distinguishes recycled aggregate from the natural aggregate and causes the recycled aggregate to have lower density and higher water absorption. ... the MFF …
Effects of Particle Shape and Packing Density on the …
A new systematic firefly algorithm for forecasting the durability of reinforced recycled aggregate concrete. Front. Struct. Civ. Eng. 2022, 16, 329–346. [Google Scholar] Amin, M.; Hakeem, I.Y.; Zeyad, A.M. Influence of recycled aggregates and carbon nanofibres on properties of ultra-high-performance concrete under elevated temperatures.
Durability of Recycled Concrete Aggregates Prepared with
The reused or recycled aggregate generated from concrete or asphalt is also considered a resource with additional high value as an option for the natural aggregate resources, ... The primary parameters used to categorize the RCA quality are water absorption and dry density, which played a vital role .
