Incorporation of recycled aggregates from construction and demolition waste in paver blocks

ABSTRACT: The consumption of natural resources and energy increased proportionally with the growth of the world population and its economic level. There was an increasing exponential consumption of natural resources, which implied an increase in environmental impacts. The construction sector is responsible for a very significant production of construction and demolition waste (CDW). Thus, there is a concern in search of a more sustainable final disposal. Many studies have been investigated the development of new materials with the incorporation of recycled aggregates from CDW. This paper presents a study of performance evaluation of concrete blocks produced with CDW. For that purpose, an experimental campaign was performed, including a characterization of the aggregates used. The incorporation of 100% of fine and coarse recycled aggregates. The mixtures were designed according to the condition of the aggregate (dry, washed or saturated). The performance of these blocks was evaluated in terms of mechanical strength and water absorption. Some additional tests were also performed to deeper analyze of the microstructure of these blocks. To assess the durability of the concrete blocks, a full-scale road was built. The results were very positive, since there were no significant differences between the modified concrete blocks and the reference sample (0% of the CDW). The modified block with fine aggregate presented the best performance of all the blocks, concerning mechanical strength. In addition, the performance of concrete blocks with washed recycled aggregates had a better performance compared to the others. The results obtained were satisfactory for the application of the blocks in the streets with low movement and low load.

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Recycled Aggregates from Construction and Demolition Waste in the Production of Concrete Blocks

Journal of Construction Materials ◽

10.36756/jcm.v2.1.6 ◽

2020 ◽

Vol 2 (1) ◽

Author(s):

Juan A. Ferriz-Papi ◽

◽

Simon Thomas ◽

◽

Keyword(s):

Reference Sample ◽

Substantial Reduction ◽

Construction And Demolition Waste ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

The European Union ◽

Demolition Waste ◽

Two Samples ◽

Concrete Blocks ◽

The Uk

The construction industry generates large amounts of waste, usually mixed, which can be composed of different origin materials, most of them catalogued as non-hazardous. The European Union targets for this waste for 2020 have been already achieved by the UK, but it is mainly developed in downcycling processes (backfilling) whereas upcycling (such as recycle in new concrete batches) still keeps at a low percentage. The aim of this paper is to explore further in the use of recycled aggregates from construction and demolition waste (CDW) in concrete mixes so as to improve upcycling. A review of most recent research and legislation applied in the UK is developed regarding the production of concrete blocks. As a case study, initial tests were developed with a CDW recycled aggregate sample from a CDW plant in Swansea. Composition by visual inspection and sieving tests of two samples were developed and compared to original aggregates. More than 70% was formed by soil waste from excavation, and the rest was a mix of waste from mortar, concrete, and ceramics with small traces of plaster, glass and organic matter. Two concrete mixes were made with 80% replacement of recycled aggregates and different water/cement ratio. Tests were carried out for slump, absorption, density and compression strength. The results were compared to a reference sample and showed a substantial reduction of quality in both mixes. Despite that, the discussion brings to identify different aspects to solve, such as heterogeneity or composition, and analyze them for the successful use of these recycled aggregates in the production of concrete blocks. The conclusions obtained can help increase upcycling processes ratio with mixed CDW as recycled aggregates in concrete mixes.

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Application of Construction and Demolition Waste in Civil Construction in the Brazilian Amazon—Case Study of the City of Rio Branco

Materials ◽

10.3390/ma14092247 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2247

Author(s):

Fernando da Silva Souza ◽

José Maria Franco de Carvalho ◽

Gabriela Grotti Silveira ◽

Vitória Cordeiro Araújo ◽

Ricardo André Fiorotti Peixoto

Keyword(s):

Mechanical Strength ◽

Raw Materials ◽

Amazon Region ◽

Construction And Demolition Waste ◽

Recycled Aggregates ◽

Federal State ◽

Construction Sites ◽

Demolition Waste ◽

Conventional Concrete ◽

Initial Adhesion

The lack of usable aggregates for civil construction in Rio Branco (capital of Acre, a Federal State in the Amazon region) makes the production and use of recycled aggregates from construction and demolition waste (CDW) an alternative of great interest. In this study, a comprehensive characterization of CDW collected from 24 construction sites of six building types and three different construction phases (structures, masonry, and finishing) was carried out. The fine and coarse recycled aggregates were produced and evaluated in 10 different compositions. The aggregates’ performance was evaluated in four mixtures designed for laying and coating mortars with a total replacement of conventional aggregates and a mixture designed for a C25 concrete with 50% and 100% replacement of conventional aggregates. CDW mortars showed lower densities and greater water retention, initial adhesion, and mechanical strength than conventional mortars. CDW concretes presented lower densities and greater resistance to chloride penetration than conventional concrete, with a small mechanical strength reduction. The recycled CDW aggregates proved to be technologically feasible for safe application in mortars and concrete; for this reason, it is believed that the alternative and proposed methodology is of great interest to the Amazonian construction industry, considering the high costs of raw materials and the need for defining and consolidating a sustainable development model for the Amazon region.

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Preliminary Analysis of the Use of Construction Waste to Replace Conventional Aggregates in Concrete

Buildings ◽

10.3390/buildings11030081 ◽

2021 ◽

Vol 11 (3) ◽

pp. 81

Author(s):

Fernando A. N. Silva ◽

João M. P. Q. Delgado ◽

António C. Azevedo ◽

António G. B. Lima ◽

Castorina S. Vieira

Keyword(s):

Compressive Strength ◽

Coarse Aggregate ◽

Recycled Aggregate Concrete ◽

Construction And Demolition Waste ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

Fine Aggregate ◽

Demolition Waste ◽

Fine Aggregates ◽

Mechanical Strengths

This work aims to study the influence of using construction and demolition waste in the replacement of coarse and fine aggregate to produce recycled aggregate concrete (RAC). A moderate compressive strength concrete made with usual fine and coarse aggregate was used as a benchmark material. Compressive and split tensile tests were performed using 120 cylindrical concrete specimens with 150 mm diameter and 300 mm length. Four-point flexural tests in reinforced beams made with conventional concrete and RAC were performed. The results obtained showed that the use of recycled fine aggregates, in both percentages of substitution investigated—50% and 100%— did not generate any deleterious influence on the values of compressive strength and split tensile strength of the RACs produced. Tin fact, the mechanical strengths of RACs produced with recycled fine aggregate were equal or higher than those from the reference concrete. The same behavior was not observed, however, when the recycled coarse aggregate was used. For this case, decreases in concrete mechanical strengths were observed, especially in compressive strength, with values around 35% lower when compared to the reference concrete. Tensile mechanical tests results confirmed the excellent behavior of all RACs made with replacement of usual fine aggregates by recycled. Bending tests performed in reinforced RAC beams had as objective to evaluate the deformation profile of the beams. The obtained results showed that RAC beams with full replacement of usual fine aggregate by the recycled aggregates have presented little changes in the global behavior, an aspect that encourages its use.

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Production of Concrete Blocks with Residues for Civil Construction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.865 ◽

2013 ◽

Vol 690-693 ◽

pp. 865-869 ◽

Cited By ~ 1

Author(s):

Marília Martinês de Camargo ◽

Rosa Cristina Cecche Lintz ◽

Luisa Andréia Gachet-Barbosa ◽

Marta Siviero Guilherme Pires

Keyword(s):

Value Added ◽

Construction And Demolition Waste ◽

Recycled Aggregates ◽

Partial Replacement ◽

Structural Function ◽

Demolition Waste ◽

Original Product ◽

Concrete Blocks ◽

Function Blocks ◽

Natural Aggregates

The Construction is recognized as one of the most important activities for the economic and social development, and on the other hand, behaves also as a major generator of environmental impacts, either by consumption of natural resources, the modification of the landscape or the generation of construction and demolition waste (CDW). Investing in an implementation of managed clean and healthy in the area of CDW is essential for the environment and for the economy of the cities, who are spending less resources on the collection, cleaning of drains and treatment of diseases. Nowadays, the amount of waste generated is considered large, occupying much space in landfills, and its transportation, depending on the volume and weight, is quite expensive. Recycling and reuse of these wastes are extremely important to control and mitigate environmental problems, as well as produce various materials value-added. Over 90% of waste can be recycled, reused and transformed into aggregates with characteristics very similar to the original product, thus creating environmentally friendly products such as sand, gravel, pebbles. This research concerns the study of the properties of concrete containing CDW, aiming its use in the manufacture of concrete blocks to seal without structural function. Blocks have been molded with partial replacement of natural aggregates by recycled aggregates and later were performed tests of compressive strength in accordance with the standards to prove the technical feasibility of the material for the trait studied.

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Concrete-Based and Mixed Waste Aggregates in Rendering Mortars

Materials ◽

10.3390/ma13081976 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1976 ◽

Cited By ~ 1

Author(s):

Samuel Roque ◽

Cinthia Maia Pederneiras ◽

Catarina Brazão Farinha ◽

Jorge de Brito ◽

Rosário Veiga

Keyword(s):

Mechanical Strength ◽

Recycled Concrete ◽

Construction And Demolition Waste ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

Accelerated Ageing ◽

Concrete Aggregate ◽

Recycled Concrete Aggregate ◽

Demolition Waste ◽

Cement Mortars

This paper presents a study of incorporation of two types of construction and demolition waste (CDW) in rendering mortars, as aggregates at 0%, 20%, 50% and 100% (by volume). Recycled concrete aggregate (RCA) and mixed recycled aggregate (MRA) were used. The former is mainly composed of cementitious waste and the latter consists of a mixture of non-segregated wastes. The performance of the cement mortars with recycled aggregates was evaluated through an extensive experimental programme. The analysis comprised workability, mechanical strength, water absorption, shrinkage, open porosity and the evaluation of durability by permeability to water under pressure after an artificial accelerated ageing test. The results are considered positive, although as the incorporation of recycled aggregates (both MRA and RCA) increased the mechanical strength, the modulus of elasticity and bulk density decreased, which leads to the production of lighter mortars that are less susceptible to cracking. The modified mortar with 20% of MRA presented the best performance, in terms of mechanical behaviour.

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Construction and Demolition Waste As Recycled Aggregate for Environmentally-Friendly Concrete Paving.

10.21203/rs.3.rs-396080/v1 ◽

2021 ◽

Author(s):

Manuel Contreras Llanes ◽

Maximina Romero Pérez ◽

Manuel Jesús Gázquez González ◽

Juan Pedro Bolívar Raya

Keyword(s):

Tensile Strength ◽

Reference Sample ◽

Production Costs ◽

Construction And Demolition Waste ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

Demolition Waste ◽

Natural Sand ◽

Natural Aggregates ◽

Sand And Gravel

Abstract Recycled aggregates (RA) from construction and demolition waste (CDW) instead of natural aggregates (NA) was analysed in the manufacture of new eco-friendly concrete. Fine (FRA) and coarse (CRA) recycled aggregates were used in different percentages as substitutes of natural sand and gravel, respectively. The results revealed that the use of RA in percentages of up to 50 wt.% are feasible. Additionally, RA were used to produce paving blocks in accordance with industrial requirements. Thus, values of water absorption lesser than 6% and tensile strength upper than 3.6 MPa were obtained, which are similar to those of a reference sample. These results were achieved by reducing the incorporation of cement, thereby saving production costs and minimizing environmental impact.

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Concrete performance evaluation of coarse aggregate replacement by civil construction waste

Revista Eletrônica em Gestão Educação e Tecnologia Ambiental ◽

10.5902/2236117043603 ◽

2020 ◽

Vol 24 ◽

pp. e52

Author(s):

Juliane Patricia Oliveira ◽

Carlos Henrique Dos Santos ◽

Maria Lúcia Okumura ◽

Natália Ueda Yamaguchi

Keyword(s):

Natural Resources ◽

Coarse Aggregate ◽

Construction And Demolition Waste ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

Construction Sector ◽

Waste Generation ◽

Demolition Waste ◽

The Sustainable Development ◽

Recycled Coarse Aggregate

The construction sector is considered a major generator of environmental impacts due to the high consumption of natural resources and waste generation. Thus, this article aims to evaluate the performance of a concrete produced by the partial and total replacement of natural coarse aggregate by recycled coarse aggregate, derived from the concrete residue of buildings and demolitions. The study was made by comparing the compressive strength and absorption of three different concrete traces, keeping the water/cement factor of 0.60 and changing only the proportions of recycled coarse aggregate between 0%, 50% and 100%. The results showed that the higher the percentage of substitution, the greater the water absorption and the lower the resistance results concrete compression. This result was obtained due to the lighter characteristic of the recycled aggregate compared to the natural aggregate. It was concluded that the concrete produced with recycled aggregates could be used in nonstructural functions, giving an adequate destination to the construction and demolition waste and consequently reducing the extraction and consumption of natural resources and contributing for the sustainable development.

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Improving the Performance of Mortars Made from Recycled Aggregates by the Addition of Zeolitised Cineritic Tuff

Crystals ◽

10.3390/cryst12010077 ◽

2022 ◽

Vol 12 (1) ◽

pp. 77

Author(s):

Domingo A. Martín ◽

Jorge L. Costafreda ◽

Leticia Presa

Keyword(s):

Mechanical Strength ◽

Amorphous Materials ◽

Volcanic Glass ◽

Secondary Phase ◽

Positive Influence ◽

Main Phase ◽

Construction And Demolition Waste ◽

Recycled Aggregates ◽

Demolition Waste ◽

Intrinsic Nature

Metropolitan construction and demolition waste (CDW) is currently an important source of recycled materials that, despite having completed their useful life cycle, can be reincorporated into the circular economy process (CEP); however, the recycling process is very selective, and waste material is not always fully satisfactory due to the intrinsic nature of the waste. This work aims to demonstrate and establish how to increase the effectiveness of the construction and demolition waste in more resistant mortars, by mixing it with zeolitised cinerite tuff (ZCT) at varying normalised proportions. To attain the objectives of this research, a series of tests were done: First, a chemical, physical and mineralogical characterisation of the CDW and the ZCT through XRF, XRD, SEM and granulometric methods. Second, a technological test was made to determine the mechanical strength at 7, 28 and 90 days of specimens made with Portland cement (PC) and mixtures of PC/CDW, PC/ZCT, and PC/CDW-ZCT. The results obtained through the characterisation methods showed that the sample of construction and demolition waste consisted of the main phase made of portlandite and tobermorite, and by a secondary phase consisting of quartz, ettringite and calcite; whereas the ZCT has a main phase of mordenite and a secondary phase of smectite (montmorillonite), amorphous materials consisting of devitrified volcanic glass, quartz and plagioclase. Mechanical strength tests established that specimens made with PC/CDW mixtures have very discreet compressive strength values up to 44 MPa at 90 days, whereas specimens made with PC/ZCT mixtures achieved a remarkably high mechanical strength consisting of 68.5 MPa. However, the most interesting conclusion in this research is the good result obtained in mechanical strength of the specimens made up of mixtures of PC/CDW-ZCT, which increased from 52.5 to 62 MPa at 90 days of curing; this fact establishes the positive influence of ZCT on waste in the mortar mixtures, which permits the authors to establish that the objective of the work has been fulfilled. Finally, it can be argued that the results obtained in this research could contribute to more effective use of construction and demolition waste in metropolitan areas.

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Applicability of recycled aggregates in concrete piles for soft soil improvement

Waste Management & Research ◽

10.1177/0734242x16676544 ◽

2016 ◽

Vol 35 (1) ◽

pp. 56-64 ◽

Cited By ~ 1

Author(s):

Ronaldo A Medeiros-Junior ◽

Carlos ET Balestra ◽

Maryangela G Lima

Keyword(s):

Compressive Strength ◽

Bearing Capacity ◽

Soft Soil ◽

Construction And Demolition Waste ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

Fine Aggregate ◽

Demolition Waste ◽

Soft Soils ◽

Natural Aggregates

The expressive generation of construction and demolition waste is stimulating several studies for reusing this material. The improvement of soft soils by concrete compaction piles has been widely applied for 40 years in some Brazilian cities. This technique is used to improve the bearing capacity of soft soils, allowing executing shallow foundations instead of deep foundations. The compaction piles use a high volume of material. This article explored the possibility of using recycled aggregates from construction waste to replace the natural aggregates in order to improve the bearing capacity of the soft soil, regarding its compressive strength. Construction wastes from different stages of a construction were used in order to make samples of concrete with recycled aggregates. The strength of concretes with natural aggregates was compared with the strength of concretes with recycled (fine and coarse) aggregates. Results show that all samples met the minimum compressive strength specified for compaction piles used to improve the bearing capacity of soft soils. The concrete with recycled aggregate from the structural stage had even higher resistances than the concrete with natural aggregates. This behaviour was attributed to the large amount of cementitious materials in the composition of this type of concrete. It was also observed that concrete with recycled fine aggregate has a superior resistance to concrete with recycled coarse aggregate.

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Caracterización físico-mecánica del hormigón estructural fabricado con áridos reciclados: comparativa experimental con sustitución de áridos finos y gruesos = Physical-mechanical characterization of the structural concrete made with recycled aggregates: experimental comparative with substitution of fine and coarse aggregates

Anales de Edificación ◽

10.20868/ade.2017.3532 ◽

2017 ◽

Vol 3 (1) ◽

pp. 24

Author(s):

Sara Valverde Fernández

Keyword(s):

Water Absorption ◽

Modulus Of Elasticity ◽

Shrinkage Strain ◽

Construction And Demolition Waste ◽

Recycled Aggregates ◽

Fine Aggregate ◽

Demolition Waste ◽

Coarse Aggregates ◽

Static Modulus ◽

Static Modulus Of Elasticity

ResumenEste trabajo estudia las propiedades mecánicas y físicas de hormigones estructurales fabricados con áridos reciclados obtenidos de residuos de construcción y demolición. Se han seleccionado mezclas con una relación específica agua / cemento y una sustitución de agregados gruesos y finos similares. Se han comparado los resultados de la deformación, la resistencia a la compresión, la resistencia a la rotura por fraccionamiento, el módulo estático de elasticidad, la deformación por contracción, la densidad aparente y los ensayos de absorción de agua. Los datos muestran que las propiedades más afectadas debido a la sustitución de agregados naturales por agregados reciclados son la trabajabilidad, el módulo de elasticidad, la deformación por contracción y la absorción de agua.AbstractThis work studies the mechanical and physical properties of structural concretes made by recycled aggregates obtained from construction and demolition waste. Mixes with a specific water/cement ratio and a similar coarse and fine aggregate substitution have been selected. Results from slump, compressive strength, splitting tensile strength, static modulus of elasticity, shrinkage strain, bulk density and water absorption tests have been compared. The data show that the most affected properties because of natural aggregate substitution for recycled aggregates are workability, modulus of elasticity, shrinkage strain and water absorption.

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