Performance of recycled aggregate concrete based on a new concrete recycling technology

Lotfi, Somayeh; Eggimann, Manuel; Wagner, Eckhard; Mróz, Radosław; Deja, Jan

doi:10.1016/j.conbuildmat.2015.07.021

Cited by 159 publications

(68 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Existing research on the matter points towards negligible influence or a slight decline in this property with increasing coarse RCA content (65,(148)(149)(150)(151)(152)(153)(154).…”

Section: Resistance To Abrasionmentioning

confidence: 99%

Recycled concrete with coarse recycled aggregate. An overview and analysis

González-Fonteboa

Seara-Paz

Brito³

et al. 2018

Mater. construcc.

View full text Add to dashboard Cite

ABSTRACT:The construction field has contributed to environmental degradation, producing a high amount of construction and demolition waste (C&D waste) and consuming large volumes of natural resources. In this context, recycled concrete (RC) has been recognised as a means to preserve natural resources and reduce space for waste storage. During the last decades, many researchers have developed works studying different recycled concrete properties.This review focuses on structural RC made with coarse recycled aggregate from concrete waste. The main objective is to provide a state of the art report on RC's properties and an analysis on how to predict them taking into account relevant research works. Moreover, the study tries to collect and update RC findings, proposing equations to define RC's performance, in terms of mechanical strength, modulus of elasticity, stress-strain, creep and shrinkage. RESUMEN:Hormigón reciclado con árido grueso reciclado. Una visión general y análisis. El campo de la construcción ha contribuido a la degradación del medio ambiente, produciendo gran cantidad de residuos de construcción y demolición y consumiendo grandes volúmenes de recursos naturales. En este contexto, el hormigón reciclado se ha presentado como una opción para preservar los recursos naturales y reducir el espacio destinado a vertedero. Así, durante las últimas décadas, muchos investigadores han desarrollado trabajos para estudiar las propiedades del hormigón reciclado.Este artículo se centra en el hormigón estructural fabricado con árido reciclado grueso procedente de residuos de hormigón. El principal objetivo es desarrollar un estado del arte que recoja las principales propiedades del hormigón reciclado y un análisis de cómo calcularlas teniendo en cuenta un gran número de trabajos relevantes en este ámbito. Adicionalmente, el estudio recopila y actualiza el conocimiento sobre estos hormigones, proponiendo ecuaciones que permitan definir sus resistencias mecánicas, módulo de elasticidad, tensión-deformación, fluencia y retracción.

show abstract

“…Existing research on the matter points towards negligible influence or a slight decline in this property with increasing coarse RCA content (65,(148)(149)(150)(151)(152)(153)(154).…”

Section: Resistance To Abrasionmentioning

confidence: 99%

Recycled concrete with coarse recycled aggregate. An overview and analysis

González-Fonteboa

Seara-Paz

Brito³

et al. 2018

Mater. construcc.

View full text Add to dashboard Cite

show abstract

“…To substitute the natural aggregates of concrete with the recycled aggregates made of mining waste and demolished concrete structures, different approaches have been investigated in recent decades [1][2][3]. Efforts have been put into improving the recycling process and technology of recycled aggregates to eliminate the defects of recycled coarse aggregate, including irregular morphology of particles, and rough surface bonded with old mortar leading to greater water absorption [4][5][6][7][8]. The mix proportion design of concrete has been adjusting by using mineral admixtures [9,10], and different approaches of recycled aggregates replacing natural aggregates.…”

Section: Introductionmentioning

confidence: 99%

“…The mix proportion design of concrete has been adjusting by using mineral admixtures [9,10], and different approaches of recycled aggregates replacing natural aggregates. These approaches include coarse natural aggregate being partially replaced by recycled coarse aggregate, natural sand partially or all replaced by recycled fine aggregate, and full use of recycled fine and coarse aggregates [2,6,11,12]. The absolute volume method has been generally accepted in the design of mix proportion to deal with the difference of density among raw materials.…”

Section: Introductionmentioning

confidence: 99%

Shear Performance of Reinforced Concrete Beams Affected by Satisfactory Composite-Recycled Aggregates

Liang

Zhao

et al. 2020

Materials

View full text Add to dashboard Cite

This paper is the outcome of experiments on the shear performance of reinforced concrete beams with approved composite-recycled aggregates. The strength grade of composite-recycled aggregate concrete (CRAC) was between 30 MPa and 60 MPa. The shear span-to-depth ratio varied from 1 to 3. The adaptability of HRB400 rebar, with critical yield strength of 400 MPa, used as stirrups was also verified. As the composite technology overcame the shortcomings of recycled coarse aggregate, CRAC had similar mechanical properties with those of conventional concrete. Details on the shear behaviors of test beams under a four-point loading test are presented. The results indicated that the changes of CRAC strain, stirrup strain, and shear-crack width depended on the failure patterns, which are controlled by the shear-span to depth ratio. The stirrups yield at the failure of reinforced CRAC beams. The shear cracking resistance and the shear capacity of reinforced CRAC beams can be predicted by the statistical equations. Based on the design codes GB50010, ACI318-19, Model Code 2010 and DIN-1045-1-2008 for conventional reinforced concrete beams, the shear strengths provided by CRAC and stirrups are statistical analyzed. The rationality of the design equations is examined by the utilization level of shear strength provided by CRAC. The maximum shear-crack widths are extracted from the test data of reinforced CRAC beams at normal service state. Comparatively, by specifying the lower limit of shear strength provided by the CRAC with various shear-span to depth ratios, China code GB50010 gives a rational method for utilizing CRAC. Under the premise that the design of shear capacity would give considerations to meet the normal serviceability, the factored strength of HRB400 rebar should be 360 MPa for the calculation of shear strength provided by stirrups. The design methods in codes of GB50010, ACI318-19 and Model Code 2010 are conservative for the shear capacity of reinforced CRAC beams.

show abstract

“…Lotfi and Al-Fayez 11) reported that the freezethaw resistance of concrete containing CRCA and FRCA at replacement rates of 20% natural aggregate is as high as that of the reference non-recycled concrete. Lotfi et al 12) investigated low-strength and moderate-strength concrete that both contained an air-entraining agent (AEA). The frost resistance of concrete samples containing normal aggregate or 100% RCA has been tested.…”

Section: Introductionmentioning

confidence: 99%

Assessment of the freeze–thaw resistance of concrete incorporating carbonated coarse recycled concrete aggregates

Wang

et al. 2017

J. Ceram. Soc. Japan

View full text Add to dashboard Cite

This study aims to characterise the freezethaw resistance of concrete incorporating carbonated coarse recycled concrete aggregate (C-CRCA) at partial or full replacement rates of coarse natural aggregate (CNA). Experimental work is conducted for C-CRCA with varying CO 2 curing time (0 day, 3 day, 7 day) and C-CRCA weight replacement percentages (0, 20, 50, 100%) for concrete production. Weight loss, relative dynamic modulus of elasticity (RDME) and residual compressive strength were monitored after 300 freezethaw cycles. Pore size distribution and crack volume variation were also measured via nuclear magnetic resonance to investigate changes in the microstructure of the concrete interior. The compressive strength of concrete decreases with the replacement percentage of CNA by the C-CRCA. The internal freezethaw resistance of concrete with C-CRCA was higher or equal to those of concrete with CRCA and CNA. The total replacement of CNA by C-CRCA led to the highest RDME, and 50% replacement of CNA by C-CRCA led to the highest residual compressive strengths after the freezethaw cycles. However, the weight loss was more severe with the increasing replacement of CNA by C-CRCA. Increasing CO 2 curing time improved the frost resistance of C-CRCA concrete. The analyses of concrete mesostructure based on pore size distribution and crack volume variation agreed with the results of RDME and the compressive strength of concrete.

show abstract

Performance of recycled aggregate concrete based on a new concrete recycling technology

Cited by 159 publications

References 29 publications

Recycled concrete with coarse recycled aggregate. An overview and analysis

Recycled concrete with coarse recycled aggregate. An overview and analysis

Shear Performance of Reinforced Concrete Beams Affected by Satisfactory Composite-Recycled Aggregates

Assessment of the freeze–thaw resistance of concrete incorporating carbonated coarse recycled concrete aggregates

Contact Info

Product

Resources

About