Models for predicting strength properties of recycled concretes made with non-treated CRCAs: Empirical approach

Ohemeng, Eric A.; Ekolu, Stephen O.; Quainoo, Harry

doi:10.1016/j.conbuildmat.2021.124585

Cited by 20 publications

(6 citation statements)

References 106 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, due to the old mortar and crushed bricks in coarse recycled aggregate (RA), the elastic modulus of RAC is lower than NAC of equal compressive strength, meaning that the equations for the elastic modulus of NAC, such as Equations ( 1) -(3), cannot apply to RAC. Therefore, many equations for the elastic modulus of RAC have been developed [4][5][6][7][8][9][10][11]. However, most of them are not practical for the estimation as they use many parameters unknown at the design stage, such as the detailed mix proportion of concrete, the aggregate type, the cement type, the aggregate size, the elastic modulus of the control concrete and so on.…”

Section: Introductionmentioning

confidence: 99%

“…It shows that Class I RA has no adverse effect on the elastic modulus. However, a little old mortar may be attached to Class I RA that reduces the elastic modulus, and Ohemeng et al [4] report that RCA made with high-quality RA may gain equal or higher compressive strength but lower elastic modulus, which means η for Class I RA should be less than 1. 2.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A Practical Equation for the Elastic Modulus of Recycled Aggregate Concrete

2022

View full text Add to dashboard Cite

For greater sustainability in construction, coarse recycled aggregate concrete (RAC) is becoming popular as a replacement for natural aggregate concrete (NAC) in structures. The elastic modulus of concrete (E) is a fundamental parameter in structure design. However, the empirical equations for E of NAC cannot apply to RAC because E of RAC is lower than NAC of equal strength, which hinders the widespread use of RAC to a certain extent. This paper provides a practical equation for E of RAC based on a comprehensive statistical analysis of 1383 mixes from 154 publications, allowing designers to easily estimate E of RAC by known parameters at the design stage, such as compressive strength, replacement rate and quality of recycled aggregate. This equation is developed by introducing a reduction factor η into the empirical equation for NAC and verified by the additional experimental results. Compared with JGJ/T443-2018 (a Chinese standard), this paper provides a more reasonable and accurate estimate by analysing much more data and taking into account other factors, such as aggregate type and the volume ratio of aggregate to paste.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

A Practical Equation for the Elastic Modulus of Recycled Aggregate Concrete

2022

View full text Add to dashboard Cite

show abstract

“…Structural concretes with a typical strength of 30 MPa and the ability to linearly lower global warming potential, according to [23]. [27] asserts that the resistance to compression load, flexural load and tensile load of RAC made from superior CRCA concretes with strengths greater than 50 MPa remain unaffected. We can infer that the strength of the original concrete affects the properties of RAC.…”

Section: Treatments To Enhance Coarse Recycled Aggregate Concrete's H...mentioning

confidence: 99%

Review on the Importance of Coarse Recycled Concrete Aggregates as Alternative Construction Materials

Kareem,

Sahoo

2024

Advanced Materials in Civil Engineering

View full text Add to dashboard Cite

Recycled concrete aggregates are one of the most important supplementary building materials used in the production of "green concrete" or recycled aggregate concrete. They are collected from construction and demolition trash, which decreases construction industry waste (RAC). By size, aggregates are divided into coarse and fine aggregate. Focus of research is on the replacement of coarse aggregate in concrete using coarse recycled concrete aggregate (CRCA). It is vital to provide a major overview on the main developments and advancements in the characterization of CRCA and in the comprehension of the behaviour of concrete containing this, taking into account its varied attributes such as freshness, hardness, and durability. Because of the weak attached mortar present on its surface, CRCA's performance in all areas falls as the replacement percentage rises. Different treatments such as washing and drying of aggregate, changed mixing sequences, carbonation, slurry and microbiological treatments, CO2 mineralization and air jigging process can mitigate the negative effects of CRCA in the concrete. This study discusses the issues raised by the widespread use of CRCA on concrete and the effectiveness of the numerous treatment solutions that are now available in the industry.

show abstract

“…For example, in Australia, 12.3 million tons (72% of total) are recovered, and 4.8 million tons (28%) are disposed of in landfills [69,70]. Recycled concrete often produces inferior performance compared to natural aggregate concrete [71,72]. As the structural performance requirement for kerb is lower compared to many other structures, it can be a suitable application area for such materials.…”

Section: Recycled Concretementioning

confidence: 99%

A Review of Current Design and Construction Practice for Road Kerbs and a Sustainability Analysis

et al. 2022

View full text Add to dashboard Cite

Kerb is an integral part of road infrastructure and performs several important functions, including providing stability to the edges of the road and providing effective drainage. Their performance can significantly influence the behaviour and service life of a road. The design conditions, construction materials and their sustainability can be important to assess from an asset management and sustainable construction point of view even though this area has been paid limited research attention in the past. This paper reviews the available literature on the design and construction considerations for kerbs and critically analyses them with a special focus on sustainable construction practice. The different materials commonly used around the world for the construction of kerb in terms of their properties, failure and available design guidelines have been discussed along with their management practice. Special situations, such as expansive soil movement and tree root-related problems, have also been considered, and the current guidelines for designing in such situations have also been discussed. A carbon footprint and sustainability analysis has been conducted on the current practice of using natural aggregate concrete and compared against several potential alternatives. The review of the design process indicated that the current practice relies on over-simplified design procedures and identified scopes for improvement, especially with the incorporation of mechanical behaviour of the material being used in construction. The carbon footprint and sustainability analysis indicated that the use of alternative materials could result in significant savings in the kerb construction industry’s carbon footprint.

show abstract

Models for predicting strength properties of recycled concretes made with non-treated CRCAs: Empirical approach

Cited by 20 publications

References 106 publications

A Practical Equation for the Elastic Modulus of Recycled Aggregate Concrete

A Practical Equation for the Elastic Modulus of Recycled Aggregate Concrete

Review on the Importance of Coarse Recycled Concrete Aggregates as Alternative Construction Materials

A Review of Current Design and Construction Practice for Road Kerbs and a Sustainability Analysis

Contact Info

Product

Resources

About