Efficient creep prediction of recycled aggregate concrete …

2.2.3. Regression tree (RT) Decision tree and regression tree are mathematical models consisting of nodes and branches [40].Generally, two branches are connected with one node, and the node deals with the data according to the feature in the node and the boundary value in the branch [41].The training process of the regression …

Comparative Environmental Impacts of Recycled Concrete Aggregate …

Construction and demolition waste (CDW) management is essential for the sustainable development of a country. Recycled concrete aggregates (RCA) manufactured from CDW can replace a significant portion of natural aggregates in concrete as per various research studies conducted. Nowadays, various alternate …

A Comprehensive Review on Recycled Aggregate and Recycled Aggregate …

Using recycled aggregates from construction and demolition waste can preserve natural aggregate resources, reduce demand of landfill, and contribute to sustainable built environment. This study provides a comprehensive review on recycled aggregate (RA) and recycled aggregate concrete (RAC) regarding their history, …

Recycled Concrete Aggregates: A Review | International …

Methods for improving the durability of recycled aggregate concrete…

Li et al. [48] used RA crushed from waste concrete with a strength grade of 50 MPa.It was found that after carbonation, the water absorption rate decreased, which is consistent with the results observed by Li [41], and the smaller the particle size, the more obvious the effect of reduced water absorption.The reason is that when the particle size …

Sustainable production of recycled concrete aggregates …

The demolished concrete as shown in Fig. 2 was obtained from concrete specimens (cubes, prisms or cylinders) tested in the Structural Engineering Laboratory of Department of Civil Engineering, IIT (BHU), Varanasi. Further, the demolished concrete was crushed by 5 kg hammer in size range of 25–4.75 mm to produce hammer crushed …

Durability assessment of recycled aggregate in concrete …

20.6. Dimensional stability of recycled aggregates concrete. Concrete durability then is its ability to overcome several types of damage by keeping its appearance, strength, and integrity for its service life of exposure to its environment (Bamigboye et al., 2017, Guo et al., 2018).The dimensional stability of RAC will be treated under the …

(PDF) Recycled concrete production: Multiple …

Its main purpose was to demonstrate the technical sustainability of multiple recycling of coarse stone aggregates originally obtained from the demolition of existing concrete elements...

A comprehensive review on the use of recycled concrete …

Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon …

A practical enhancing method of recycled concrete aggregates …

The properties and reuse of recycled aggregate concrete (RAC) are markedly limited by the defects of RCAs, highlighting the need to effectively enhance the properties of RCAs. However, the presented individual enhancing methods of RCAs, such as mechanical grinding (MG) and bio-deposition enhancement, both have some inferior …

Experimental Study of Compressive Strength of …

aggregate is used coarse aggregate I (grit, which is 10 mm down) and coarse aggregate II (20 mm down). Recycled Concrete Aggregate: The C&D waste was collected from Varachha Road near old Gitanjali Cinema at Surat. The demolished structure named "Shree Ram hospital" was mainly used for public and residential purpose.

Prediction of compressive strength of recycled aggregate concrete …

In the recycled aggregate concrete, the adherence of mortar in the concrete affects the hardness of the aggregates as well as results in increased water absorption. These properties result in a detrimental impact on the concrete's performance especially in its hardened states (e.g. compressive strength).

Environmental Assessment of Two Use Cycles of Recycled Aggregate Concrete

The main goal of this study was to compare two use cycles of natural aggregate concrete and recycled aggregate concrete, which is another way to compare the environmental impacts of recycled materials. A series of concrete mixtures with various replacement ratios of primary resources with recycled ones were prepared for …

Prediction on CO 2 uptake of recycled aggregate concrete

Carbonation of concrete is a process which absorbs carbon dioxide (CO2). Recycled aggregate concrete (RAC) may own greater potential in CO2 uptake due to the faster carbonation rate than natural aggregate concrete (NAC). A quantitative model was employed to predict the CO2 uptake of RAC in this study. The carbonation of RAC and …

Accelerated carbonation of recycled concrete aggregates …

1. Introduction. Demolished concrete can be crushed to obtain recycled concrete aggregates (RCA) that are used to produce recycling concrete. The motivation of this approach is to move towards a circular material flow in the construction industry and to preserve the limited sources of natural aggregates [[1], [2], [3], [4]].Moreover, RCA …

Experimental investigation and comparative machine …

Recycled aggregates (RA) can provide a sustainable solution for replacing natural aggregates (NA) in the concrete mix. However, the stakeholders and inspection professionals lack confidence in predicting their compressive strength (CS) due to limited databases. Most of them solely focus on the concrete mix with natural aggregates only. …

Recycled Aggregate Concrete (RAC)

Requirement for coarse recycled concrete aggregate (RCA) as per BS8500 Importance of Recycling Aggregates for Concrete. Recycled aggregates are collected from CDW (Construction and demolition waste) as the amount of CDW has increased significantly over past few years. From a study it is estimated that nearly 70 …

Background of recycled concrete aggregate used in Japan

In Japan, recycled concrete aggregate (RCA) and recycled-aggregate concrete (RAC) are standardized in the Japanese Industrial Standards (JIS) A 5021–5023. The differences between the specifications in JIS and those in foreign countries are explained. In Japan, the durability of RAC under severe conditions, particularly freezing …

Influence of Waste Brick Powder in the Mechanical …

Brick and concrete are the main materials contributing to demolition and construction waste. Considering this precedent, the effects of using both residuals in medium strength concretes are analyzed. Waste brick …

A review of life cycle assessment of recycled aggregate concrete

NO. Functional unit Detailed descriptions; FU 1: Volume: The environmental impact of 1 m 3 RAC with different aggregate replacements is compared with that of 1 m 3 natural aggregate concrete (NAC) [86], [81], [13]: FU 2: Combining volume and strength: The functional unit is chosen as 1 m 3 of concrete. The mix proportion of NAC and RAC …

Design Strategy for Recycled Aggregate …

Currently, a number of disadvantages hampers the use of recycled concrete aggregates (RCA). The current review proves that concretes made with complete replacement of natural aggregate with …

Stress-Strain Behavior of FRP-Confined Recycled Aggregate Concrete

A large amount of research has been conducted on recycled aggregate concrete (RAC) due to its social, environmental, and economic significance. However, the in situ application of RAC has so far been mainly limited to nonstructural purposes, as the performance of RAC, in both the short and long term, is inferior to its normal concrete ...

RETRACTED: Properties of Normal and Recycled Brick Aggregates …

This study compares the properties of normal and recycled brick aggregates to produce a medium range (25–30 MPa) compressive strength of structural grade concrete. Up to date, brick aggregates are commonly used in structural concrete in some South Asian and African countries. Many concrete structures which were built in …

Investigating the Alkali-Silica Reaction of Recycled Glass Aggregates

"Performance of fly ash concrete with recycled glass aggregate." Proc., TRB Annual Meeting (CD-ROM), Paper No. 09-1570, Transportation Research Board, Washington, D.C. Google Scholar. Bleszynski, R. F., and Thomas, M. D. A. (1998). "Microstructural studies on alkali-silica reaction in fly ash concrete immersed …

Production of Recycled Plastic Aggregates and Its Utilization in Concrete

A novel aggregate (RPA) comprising recycled plastic was developed. The aggregate produced was lightweight, with a density ranging from 510 to 750k kg/m³ and absorption of from 2.7 to 9.81%.

Recycled Aggregates for Concrete Production: State-of-the …

A review of the use of recycled aggregates from construction and demolition waste and slag in concrete, with a focus on the codes and norms that regulate their …

Production of Roller Compacted Concrete Made of Recycled …

This research aims to evaluate the potential using of recycled asphalt pavement aggregate (RAP), recycled concrete aggregate (RCA) and silica fume (SF) in production of roller compacted concrete (RCC). Thirty RCC mixes were casted in which natural aggregates (NA) were totally replaced by RAP and RCA with (90% and 10%), …

Recycled Concrete as Aggregate for Structural Concrete Production

A comparative analysis of the experimental results of the properties of fresh and hardened concrete with different replacement ratios of natural with recycled coarse aggregate is presented in the paper. Recycled aggregate was made by crushing the waste concrete of laboratory test cubes and precast concrete columns. Three types of …

Economical Assessment of Recycled Asphalt Pavement (RAP) Aggregate …

Structural concrete aggregate can be substituted with sustainable alternatives from construction and demolition waste, such as reclaimed asphalt pavement (RAP). This contribution assesses the RAP aggregate production chain and aims to investigate the economic aspect of RAP aggregate, evaluating the costs associated …

Microstructural analysis of recycled aggregate concrete …

From these three types of recycled coarse aggregate, C1, C2 and C3, and two types of recycled fine aggregate, F1 and F2, four types of suggested RAC applications are recommended for civil and building works, as tabulated in Table 2.Among the three types of civil engineering applications of RAC, namely, CI, CII and CIII with respect to …

Recycled Aggregate in Concrete: Use of Industrial, …

The widespread use of this material has led to continuous developments such as ultra-high strength concrete and self-compacting concrete. Recycled Aggregate in Concrete: Use of Industrial, Construction and Demolition Waste focuses on the recent development which the use of various types of recycled waste materials as aggregate in the production ...

Prediction of Shear Strength of Reinforced Recycled Aggregate Concrete

For decades, recycled coarse aggregate (RCA) has been used to make recycled aggregate concrete (RAC). Numerous studies have compared the mechanical properties and durability of recycled aggregate concrete (RAC) to those of natural aggregate concrete (NAC). However, test results on the shear strength of reinforced …

Performance of concrete made with commercially produced coarse recycled

This grading and a fine-to-coarse aggregate ratio of 46:54 were kept constant throughout the test program for all concrete mixtures. Based on visual inspection, the surface texture of the plant-crushed recycled concrete aggregate appeared characteristically grainy compared to the basalt.

Production of sustainable and structural fiber reinforced recycled

Fiber reinforced recycled aggregate concrete (FRAC) is one such material that has gained popularity since the beginning of twenty-first century due to its high strength, eco-friendly, and cost-effectiveness benefits. Fiber reinforcement in recycled aggregate concrete (RAC) tends to reinforce and retard the crack propagation and thus …

Use of recycled aggregate concrete in structural members: a …

This article presents a comprehensive review on the use of recycled concrete aggregate (RCA) and recycled aggregate concrete (RAC) in construction, …

A review of recycled aggregate in concrete applications …

The global aggregate production of 40 billion tons (Fig. 1) is an indication of the vast development projects which are materializing around the world [1].As the land for landfill becomes scarce and the world demand of aggregate reaches to an enormous 40 billion tons annually, ways to use C&D waste is gaining importance due to legislation, it …