scholarly journals Suitability Investigation of Recycled Concrete Aggregates for Concrete Production: An Experimental Case Study

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Woubishet Zewdu Taffese
Keyword(s):  
Construction Materials ◽  
Waste Recycling ◽  
Normal Weight ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Concrete Aggregate ◽  
Hardened Concrete ◽  
Demolition Waste ◽  
Concrete Production ◽  
The Difference

In developing countries, construction and demolition waste (CDW) is disposed to landfill, causing social, environmental, and economic crises. In these nations, CDW exponentially increase due to their rapid economic growth, industrialization, and urbanization. This paper aims to examine the possibility of recycling concrete waste for production of new concrete in Ethiopia. Physical and mechanical characteristics of recycled concrete aggregate (RCA) acquired from concrete waste are thoroughly examined. Though the RCA exhibited relatively lesser performance compared with the natural coarse aggregate (NCA), it reveals the same properties as of normal-weight aggregates in several instances. The performance of concrete specimens which employ RCA up to 20% is evaluated from workability, strength, and permeability aspects. The utilization of RCA slightly affects the workability and the water permeability properties of the concretes. Replacement of 10% of the NCA by the RCA enhances the compressive strength of the hardened concrete by 8%. The difference between the splitting tensile strength of the concretes which employ RCA and conventional aggregates is trivial. Generally, this work demonstrates the practicability of concrete waste recycling to produce new concrete or construction materials in Ethiopian context.

scholarly journals Reduction of the Cement Content by Incorporation of Fine Recycled Aggregates from Construction and Demolition Waste in Rendering Mortars

2021 ◽  
Vol 6 (1) ◽  
pp. 11
Author(s):  
Sara Jesus ◽  
Cinthia Maia Pederneiras ◽  
Catarina Brazão Farinha ◽  
Jorge de Brito ◽  
Rosário Veiga
Keyword(s):  
Cement Content ◽  
Construction Materials ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Concrete Aggregate ◽  
Demolition Waste ◽  
Construction And Demolition Wastes ◽  
Hardened State

The construction sector is responsible for one third of the total wastes produced in the EU. Finding solutions for the reuse or recycling of these wastes is one of the major environmental concerns of modern times. The replacement of sand or cement in specific construction materials, such as concrete or mortars, is a possible solution for these wastes’ management. By using construction and demolition wastes in construction materials, namely on buildings, the cycle of circular economy is closed, increasing the life cycle of the wastes in the same sector. In this research, a reduction of cement content in rendering mortars is analysed. This reduction is achieved by a decrease of the cement/aggregate ratio simultaneously with the incorporation of very fine recycled aggregate from construction and demolition waste. Two recycled aggregates were studied: recycled concrete aggregate (RCA) and mixed recycled aggregate (MRA). The fresh and hardened state properties of the mortars were analysed. Several tests were carried out to evaluate the mortars’ performance, such as mechanical strength tests, water absorption tests, drying tests and shrinkage. It was noticed that the incorporation of RCA led to a better behaviour than in the reference mortar, in terms of mechanical strengths and protection against water.

scholarly journals Experimental Study with Cement Mortars Made with Recycled Concrete Aggregate and Reinforced with Aramid Fibers

2021 ◽  
Vol 11 (17) ◽  
pp. 7791
Author(s):  
Alberto Morón ◽  
Daniel Ferrández ◽  
Pablo Saiz ◽  
Carlos Morón
Keyword(s):  
Construction Materials ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregates ◽  
Mechanical Resistance ◽  
Concrete Aggregate ◽  
Recycled Concrete Aggregate ◽  
Aramid Fibers ◽  
Demolition Waste ◽  
Cement Mortars

The reuse of construction and demolition waste is a necessary way to achieve greater sustainability in building, introducing the criteria of the so-called circular economy in the design of the production process of new construction materials. This research focuses on analyzing the properties of mortars made with recycled aggregates from concrete waste and reinforced with aramid fibers. For this purpose, an experimental campaign was carried out, including chemical, physical, mechanical and durability tests, performing a statistical analysis to discuss the different properties analyzed. The results show how the incorporation of aramid fibers in the matrix of cement mortars made with recycled concrete aggregate improves their technical performance and mechanical resistance, thus increasing their application possibilities and achieving similar results in some properties to those obtained with traditional mortars made with natural aggregate.

scholarly journals Influence of hydraulic jigging of construction and demolition waste recycled aggregate on hardened concrete properties

2021 ◽  
Vol 14 (3) ◽  
Author(s):  
Iago Lopes dos Santos ◽  
Luciana Vanni Frantz ◽  
Angela Borges Masuero
Keyword(s):  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Hardened Concrete ◽  
Demolition Waste ◽  
Coarse Aggregates ◽  
Concrete Properties ◽  
Concrete Production ◽  
Wide Scale

abstract: Concern with the maintenance of natural resources has increased research about recycled aggregates for concrete production. However, the heterogeneity of recycled aggregates is one of the main constraints for their use in practice, because it can generate variability in concrete properties, hence reducing their final quality. Then, the jigging has been seen as a promising way of improving recycled aggregate quality. This paper aimed to evaluate its use for better application in concrete. A modified jig was used to sort recycled coarse aggregates. Concrete were produced with water/cement ratio from 0.5 and 100% of recycled coarse aggregate. The recycled aggregate properties upgrade were achieved and the results of compressive strength and modulus of elasticity of recycled concrete made with aggregate which were submitted to jigging were increased, indicating a potential application in wide scale.

Use of Construction and Demolition Waste in Lateritic Concrete

2014 ◽  
Vol 600 ◽  
pp. 386-395
Author(s):  
Taíssa Guedes Cândido ◽  
Yane Coutinho ◽  
Milton Bezerra das Chagas Filho
Keyword(s):  
Coarse Aggregate ◽  
Production Costs ◽  
Construction And Demolition Waste ◽  
Viable Alternative ◽  
Economic Damage ◽  
Hardened Concrete ◽  
Demolition Waste ◽  
Public Places ◽  
Environmental Preservation ◽  
Concrete Production

In recent decades the problem of construction and demolition waste has been receiving more attention due to possible ecological and economic damage caused by them. This is because they are produced in large quantities and often receive inadequate disposal, being deposited illegally in vacant lots, public places and even in areas of environmental preservation. The practice of recycling of construction and demolition waste (CDW) by construction is an alternative that minimizes the amount of waste generated and the impacts caused by them. Moreover, the introduction of alternative materials might reduce the production costs of construction. In Brazil, there is great availability of lateritic concretions. This material, according to some studies, proved to be a viable alternative to be used as coarse aggregate in concrete production. In this study, it is used the CDW as a filler to replace 10% of Portland cement and, as coarse aggregate, lateritic concretions. Tests of physical properties of coarse and fine aggregates and determination of the mechanical strength of hardened concrete were made. The construction and demolition waste used as filler to replace the mass of cement in the mixture proved to be a viable alternative.

scholarly journals Influence of Partial Coarse Fraction Substitution of Natural Aggregate by Recycled Concrete Aggregate in Hot Asphalt Mixtures

2019 ◽  
Vol 12 (1) ◽  
pp. 250 ◽  
Author(s):  
Debora Acosta Álvarez ◽  
Anadelys Alonso Aenlle ◽  
Antonio José Tenza-Abril ◽  
Salvador Ivorra
Keyword(s):  
Asphalt Concrete ◽  
Coarse Fraction ◽  
Asphalt Mixtures ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Recycled Concrete Aggregate ◽  
Demolition Waste ◽  
Natural Aggregate

The main objective of this work is to evaluate the properties of hot asphalt mixtures that have been manufactured with different recycled concrete aggregate (RCA) percentages (0%, 20%, 40%, 60% and 80% of the fraction 5–13 mm) and asphalt (4%, 4.5% and 5%). Dense asphalt mixtures were made; partially replacing the natural aggregate (NA) fraction between 5 and 13 mm. Marshall specimens were manufactured to determine the main properties of the asphalt concrete (AC) in terms of density, voids, stability and deformation. Additionally, the optimal asphalt content (OAC) was determined, and measured the water sensibility, the stiffness modulus and the permanent deformation. The results corroborate the potential for using these sources of construction and demolition waste (CDW) as a RCA in asphalt concrete and show that the hot asphalt mixtures with up to 40% substitution of natural aggregate by recycled aggregate in the fraction 5–13 mm present good behavior.

A Brief Analysis of Domestic Construction and Demolition Waste Recycling Techniques

2012 ◽  
Vol 509 ◽  
pp. 1-5
Author(s):  
Su Ping Cui ◽  
Qi Dong Liu ◽  
Jian Hua Yan ◽  
Xin Du
Keyword(s):  
Natural Disaster ◽  
Waste Recycling ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Demolition Waste ◽  
Construction Waste ◽  
Healthy Development ◽  
Industrial Chain ◽  
Recycling Techniques

In this paper, the construction and demolition waste (C&D waste) recycling techniques in China is summarized, and proposed the C&D waste recycling suggestions in this foundation. The C&D waste can be divided into construction waste, decorating waste, demolition waste and natural disaster ruin waste. In addition to be buried, domestic C&D waste can be made into landscape material, roadbed material, recycled aggregate, recycled brick, recycled concrete, recycled admixture and so on. The state should establish positive promoting policies, improve the recycling industrial chain, and promote the healthy development of the C&D waste recycling.

Estimation of Water Absorption Capacity of Hardened Concrete with Recycled Aggregate Based on Experimental Determination

2015 ◽  
Vol 732 ◽  
pp. 411-414 ◽  
Author(s):  
Tereza Pavlů ◽  
Magdaléna Šefflová
Keyword(s):  
Water Absorption ◽  
Negative Impact ◽  
High Water ◽  
Absorption Capacity ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Hardened Concrete ◽  
Water Absorption Capacity ◽  
Demolition Waste

Recycled construction and demolition waste, especially recycled concrete, is able to use as an aggregate for concrete. The high water absorption capacity (WA) of recycled aggregate has a negative impact of concrete mix workability and influences the water-cement ratio. This paper presents results of experimental measurement of WA of recycled aggregate and recycled concrete. Series of concrete samples with various replacement ratios of natural aggregate and recycled aggregate were prepared for this study. The main aim of this study is to analyze the influence of recycled aggregate WA, and mixture ratios on the WA of hardened concrete (HC). Regression model to estimate the WA of hardened concrete is presented.

scholarly journals Concrete-Based and Mixed Waste Aggregates in Rendering Mortars

2020 ◽  
Author(s):  
Cinthia Maia Pederneiras
Keyword(s):  
Mechanical Performance ◽  
Ceramic Materials ◽  
Cementitious Materials ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregates ◽  
Concrete Aggregate ◽  
Demolition Waste ◽  
Recycled Concrete Aggregates ◽  
Mixed Recycled Aggregates

The construction industry is considered the biggest waste producer in Europe. In order to encourage recycling, European Parliament decreed through the Waste Framework Directive 2008/98/EC, that at least 70% of construction and demolition waste should be recycled by 2020. From recycling plants, three types of recycled aggregates are produced. Recycled Concrete Aggregate, mainly from cementitious waste, as such as concrete and mortars residues; Recycled Masonry Aggregates mainly composed by recycled ceramic materials, as such as tiles and bricks residues; Mixed Recycled Aggregates based on rubble residues, from heterogenous materials waste. This research evaluated the technical feasibility of rendering mortars with Recycled Concrete Aggregates and Mixed Recycled Aggregates, in different volume incorporation of 0%, 20%, 50% and 100%. The experimental programme comprised an analyse of the fresh and hardened properties, regarding the water and mechanical behaviour of the mortars. From the results, it was noticed that the modified mortars presented a reduction in the modulus of elasticity, which its correlated to a less susceptibility to cracking. Regarding mechanical performance, the modified mortars obtained reduction of the flexural and compressive strength over time. However, it was not a significant harmful criterion. Therefore, the incorporation of recycled aggregates in cementitious materials is considered a technical and sustainable solution.

scholarly journals PROPERTIES OF RECYCLED AGGREGATE CONCRETE

2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Mirjana Malešev ◽  
Vlastimir Radonjanin ◽  
Gordana Broćeta
Keyword(s):  
Great Powers ◽  
Recycled Concrete ◽  
Recycled Aggregate Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Demolition Waste ◽  
Aggregate Concrete ◽  
Recycling Industry ◽  
Concrete Mixtures

Following an example of the world's great powers that developed the recycling industry after natural disasters and wars, the paper points to the possibility of using large quantities of construction and demolition waste, generated as a result of the recent floods in the BiH and Serbia. Based on the years of extensive experimental research, and the research conducted by eminent experts, an overview is provided of the most basic properties and application of recycled aggregate concrete. It has been shown that the application of coarse recycled concrete aggregate, as the component materials in the concrete mixtures, it is possible to produce structural concrete that can be satisfactory and even with high quality, which primarily depends on the characteristics of crushed demolished concrete.

EFFECT OF RECYCLED CONCRETE AGGREGATE QUALITY ON PROPERTIES OF CONCRETE

2020 ◽  
Vol 15 (2) ◽  
pp. 57-69
Author(s):  
Daniel Hatungimana ◽  
Şemsi Yazıcı ◽  
Ali Mardani-Aghabaglou
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Water Absorption ◽  
Recycled Concrete ◽  
Recycled Aggregates ◽  
Concrete Aggregate ◽  
Hardened Concrete ◽  
Recycled Concrete Aggregate ◽  
Waste Concrete ◽  
Concrete Production

ABSTRACT The possibility of the use of recycled aggregates from the construction industry in green concrete production is of increasing importance to reduce the negative environmental impact associated with construction and demolition wastes. The objective of this study is to investigate the effect of recycled concrete aggregate (RCA) quality on the properties of hardened concrete properties such as compressive strength, splitting tensile strength, density, water absorption capacity and porosity accessible to water. The RCA used in this study was obtained from the crushing of waste concrete with two different compressive strengths (LRCA obtained from the crushing of waste concrete having compressive strengths below 30 MPa and HRCA obtained from the crushing of waste concrete having compressive strengths above 30 MPa). The natural coarse limestone aggregate was 100% replaced with coarse LRCA and HRCA. As a result of the study, the use of 100% HRCA and %100 LRCA instead of limestone coarse aggregate in the concrete adversely affected its mechanical and physical properties. In addition, HRCA showed better performance in terms of compressive strength, tensile strength, water absorption and porosity compared to the use of LRCA. Furthermore, the percentage of adhered mortar on the surface of LRCA and HRCA was analyzed using a computerized micro tomography device, and it was found that the percentages of attached mortar and aggregates are 61% and 35.5% for LRCA, whilst the attached mortar and aggregate contents for HRCA are 45.9% and 53.7%, respectively.

Sign in / Sign up

Export Citation Format

Share Document