Research on Mixture Ratio of Recycled Concrete Aggregate in Concrete

2012 ◽  
Vol 193-194 ◽  
pp. 1371-1375
Author(s):  
Yong San Cheng ◽  
Ke Qiang Yu ◽  
Shuang Xi Wang
Keyword(s):  
Mechanical Properties ◽  
Experimental Investigation ◽  
Raw Materials ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Recycled Concrete Aggregate ◽  
Mixture Ratio

In order to better understand the recycled concrete aggregate, it is essential to investigate the different mixture ratio in it. For determining the better mixture ratio of recycled concrete aggregate, the experimental investigation was conducted by making use of recycled concrete aggregate of different ratio instead of small stones in concrete, while maintaining the proportion of other raw materials of concrete unchanged. Its mechanical properties were also investigated. It is found that the better materials proportion of recycled concrete is that sand: recycled aggregate: water= 1: 1.8 : 2.1: 0.55.

High Performance Concrete with SCM and Recycled Aggregate

2016 ◽  
Vol 677 ◽  
pp. 233-240 ◽  
Author(s):  
Wojciech Kubissa ◽  
Roman Jaskulski ◽  
Artur Koper ◽  
Marcin Supera
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
High Performance Concrete ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Waste Materials ◽  
Concrete Aggregate ◽  
Reinforced Concrete Structures ◽  
Recycled Concrete Aggregate ◽  
Class F Fly Ash

In the article the possibility of utilization of two waste materials: Recycled Concrete Aggregate (RCA) fraction 4-16 mm and Class F fly ash (from coal burning power plant) in high perfor-mance concrete (HPC) was presented. Concrete with RCA were made with varying amount of cement and Suplementary Cementing Materials (SCM). The specimens of concrete were tested to compare mechanical properties as well as some properties related to the durability of concrete. Compression strength values up to 71.40 MPa were achieved and good values of properties determinig durability of reinforced concrete structures.

Mechanical Properties of Concrete Using Treated Recycled Concrete Aggregate in Marine Environment

2020 ◽  
Vol 841 ◽  
pp. 138-143
Author(s):  
Sallehan Ismail ◽  
Mahyuddin Ramli
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Marine Environment ◽  
Impact Resistance ◽  
Recycled Concrete ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Recycled Concrete Aggregate ◽  
Curing Conditions

This study also investigates the effectiveness of multiple surface modification of recycled concrete aggregate (RCA) with respect to mechanical properties of the resultant recycled aggregate concrete (RAC) when exposed to various curing conditions, namely, normal water (Nw) and seawater (Sw). The properties included compressive and flexural strength and impact resistance. Findings show that effect inclusion of the treated coarse RCA is significant in enhancing the mechanical properties of RAC. The exposure to Sw appears to affect the degradation of the compressive strength of RAC remarkably in a marine environment. In this case, however, using of treated RCA is found beneficial in decreasing the deterioration in the compressive strength of RAC.

scholarly journals Influence of Impregnation of Recycled Concrete Aggregate on the Selected Properties of Concrete

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4611
Author(s):  
Roman Jaskulski ◽  
Pavel Reiterman ◽  
Wojciech Kubissa ◽  
Yaroslav Yakymechko
Keyword(s):  
Mechanical Properties ◽  
Cement Paste ◽  
Water Glass ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Impregnation Method ◽  
Recycled Concrete Aggregate ◽  
Freezing And Thawing ◽  
Durability Properties

The paper focuses on investigating the effect of impregnation of recycled concrete aggregate on the mechanical and durability properties of concrete using this aggregate. Cement paste, limewater and diluted water glass were used to impregnate the aggregate. Both a single impregnation and a double impregnation using two different solutions were carried out. A total of four groups of concrete series, with two values of w/c ratio (0.45 and 0.60), were made. Concrete made using the impregnated aggregate was tested and the results were compared with those of concrete made using untreated recycled aggregate of the same kind. The results indicate that impregnation of aggregate improves the mechanical properties of concrete in many cases but reduces its resistance to cyclic freezing and thawing. Furthermore, in the case of impregnation with two solutions, the order in which the impregnants are applied influences the effect obtained. Using the results received, the impregnation methods were ranked in order from best to worst. The best impregnation method proved to be with cement paste, followed by diluted water glass, while the worst results were obtained with limewater, followed by diluted water glass.

scholarly journals Mechanical properties of roller compacted concrete containing recycled concrete aggregate

2021 ◽  
Vol 20 (2) ◽  
pp. 277-290
Author(s):  
Hojjat Hosseinnezhad ◽  
◽  
Daniel Hatungimana ◽  
Şemsi Yazıcı ◽  
◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Detrimental Effect ◽  
Impact Resistance ◽  
Pulse Velocity ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Recycled Concrete Aggregate ◽  
Limestone Aggregate ◽  
Roller Compacted Concrete

The compressive strength, splitting tensile strength, pulse velocity, and drop weight impact resistance of roller-compacted concrete (RCC) mixtures containing recycled concrete aggregate (RCA) were investigated. The cement contents of the RCC mixtures were chosen as 150, 200 and 250 kg/m3. In addition to the control mixtures containing no RCA, 25, 50, 75, and 100 wt% of the crushed limestone aggregate was replaced with RCA. In this way, 15 RCC mixtures were prepared. The water content of RCC mixtures was determined by the maximum density method. The results showed that increasing the amount of recycled aggregate decreased the mechanical properties of the concrete. However, up to 25% replacement level, recycled aggregate had not a significant detrimental effect on the properties of RCC. Besides, the detrimental effect of RCA substitution was more pronounced in leaner mixtures and reduced by increasing the cement content of the RCC.

scholarly journals Scanning Electron Microscopy of Metakaolin Based Geopolymer Concrete

2021 ◽  
Vol 2114 (1) ◽  
pp. 012061
Author(s):  
Layth Al-Jaberi ◽  
Al-Saraj K. Wissam Al-Saraj ◽  
Al-Serai J. Sahar Al-Serai
Keyword(s):  
Mechanical Properties ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Geopolymer Concrete ◽  
Recycled Concrete Aggregate ◽  
Normal Concrete ◽  
Sem Study ◽  
Concrete Mix ◽  
Scanning Electron

Abstract This work is a Scanning Electron Microscope (SEM) study to investigate the behaviour of Metakaolin based GPC mixes with and without cement and containing recycled concrete aggregate. Three (3) GPC mixes and Normal Concrete mix (NC) designed mingled and tested to achieve the goals of this research. Control specimens were cast from each mix to determine the mechanical properties for each mix. (12) SEM micrographs from carefully selected samples. SEM study confirmed that the presence of recycled concrete aggregate can be a source of generating cracks and fissures. The un-hydrated cement particles in recycled aggregate can contribute to further hydration when contact with water. Also, the metakaolin based GPC matrix with natural aggregate showed enormous with unrealized morphology, which indicates amorphous. Finally, the replacement of 20% of Metakaolin with cement led to enhance mechanical properties.

scholarly journals Roller Compacted Concrete with Recycled Concrete Aggregate for Paving Bases

2020 ◽  
Vol 12 (8) ◽  
pp. 3154 ◽  
Author(s):  
Hedelvan Emerson Fardin ◽  
Adriana Goulart dos Santos
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Modulus Of Elasticity ◽  
Splitting Tensile Strength ◽  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Recycled Concrete Aggregate ◽  
Roller Compacted Concrete ◽  
Flexural Tensile Strength ◽  
Mechanical And Physical Properties

This research aimed to investigate the mechanical and physical properties of Roller Compacted Concrete (RCC) used with Recycled Concrete Aggregate (RCA) as a replacement for natural coarse aggregate. The maximum dry density method was adopted to prepare RCC mixtures with 200 kg/m³ of cement content and coarse natural aggregates in the concrete mixture. Four RCC mixtures were produced from different RCA incorporation ratios (0%, 5%, 15%, and 30%). The compaction test, compressive strength, splitting tensile strength, flexural tensile strength, and modulus of elasticity, porosity, density, and water absorption tests were performed to analyze the mechanical and physical properties of the mixtures. One-way Analysis of Variance (ANOVA) was used to identify the influences of RCA on RCC’s mechanical properties. As RCA increased in mixtures, some mechanical properties were observed to decrease, such as modulus of elasticity, but the same was not observed in the splitting tensile strength. All RCCs displayed compressive strength greater than 15.0 MPa at 28 days, splitting tensile strength above 1.9 MPa, flexural tensile strength above 2.9 MPa, and modulus of elasticity above 19.0 GPa. According to Brazilian standards, the RCA added to RCC could be used for base layers.

Recycling of Waste Concrete and Fly Ash for Recycled Aggregate Concrete: Fundamental Characteristics Evaluation

2009 ◽  
Vol 620-622 ◽  
pp. 255-258 ◽  
Author(s):  
Cheol Woo Park
Keyword(s):  
Fly Ash ◽  
Recycled Concrete ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Experimental Program ◽  
Concrete Aggregate ◽  
Fine Aggregate ◽  
Recycled Concrete Aggregate ◽  
Aggregate Concrete ◽  
Waste Concrete

As the amount of waste concrete has been increased and recycling technique advances, this study investigates the applicability of recycled concrete aggregate for concrete structures. In addition fly ash, the industrial by-product, was considered in the concrete mix. Experimental program performed compressive strength and chloride penetration resistance tests with various replacement levels of fine recycled concrete aggregate and fly ash. In most case, the design strength, 40MPa, was obtained. It was known that the replacement of the fine aggregate with fine RCA may have greater influence on the strength development rather than the addition of fly ash. It is recommended that when complete coarse aggregate is replaced with RCA the fine RCA replacement should be less than 60%. The recycled aggregate concrete can achieve sufficient resistance to the chloride ion penetration and the resistance can be more effectively controlled by adding fly ash. It I finally conclude that the recycled concrete aggregate can be successfully used in the construction field and the recycling rate of waste concrete and flay ash should be increased without causing significant engineering problems.

scholarly journals Recycled Concrete Aggregate for Medium-Quality Structural Concrete

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4612
Author(s):  
Dong Viet Phuong Tran ◽  
Abbas Allawi ◽  
Amjad Albayati ◽  
Thi Nguyen Cao ◽  
Ayman El-Zohairy ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Coarse Aggregate ◽  
Pulse Velocity ◽  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Predictive Equation ◽  
Recycled Concrete Aggregate ◽  
Structural Concrete ◽  
Medium Quality ◽  
Ultrasound Pulse

This paper reports an evaluation of the properties of medium-quality concrete incorporating recycled coarse aggregate (RCA). Concrete specimens were prepared with various percentages of the RCA (25%, 50%, 75%, and 100%). The workability, mechanical properties, and durability in terms of abrasion of cured concrete were examined at different ages. The results reveal insignificant differences between the recycled concrete (RC) and reference concrete in terms of the mechanical and durability-related measurements. Meanwhile, the workability of the RC reduced vastly since the replacement of the RCA reached 75% and 100%. The ultrasound pulse velocity (UPV) results greatly depend on the porosity of concrete and the RC exhibited higher porosity than that of the reference concrete, particularly at the transition zone between the RCA and the new paste. Therefore, the sound transmission in the RC required longer times than that in the reference concrete. Moreover, a predictive equation relating the compressive strength to the UPV was developed.

scholarly journals Influence of different monomer ratios and recycled concrete aggregate on mechanical properties and durability of geopolymer concretes

2019 ◽  
Vol 205 ◽  
pp. 519-528 ◽  
Author(s):  
Mahdi Koushkbaghi ◽  
Pedram Alipour ◽  
Behzad Tahmouresi ◽  
Ehsan Mohseni ◽  
Ashkan Saradar ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Recycled Concrete Aggregate
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