Prediction of the mechanical behavior of recycled concrete with fresh concrete waste aggregate

Recycled aggregate (RA) acknowledge with its inferior quality due to high water absorption and lower strength which is mainly due to presence of attached adherent mortar. Concrete made with RA have lower strength and durability properties when compared with natural aggregate concrete (NAC), recorded by many previous researches in past. In order to overcome these difficulties, two‐stage mixing approach (TSMA) is a good tool to improve the properties of recycled aggregate concrete when compared with normal mixing approach (NMA). The main objective of present research work is to study the influence of mixing approaches on concrete made with treated recycled aggregate (TRA). Basically the workability, mechanical and durability properties of concrete have been studied at fresh and hardened state. In this work, four different types of mixing approaches (viz. NMA, TSMA, TSMA1, and TSMA2) were used. In all types of mixing approaches, the natural aggregate was replaced with TRA at different replacement levels viz.: 0, 25, 50, 75, and 100% in a control mix of M40 grade. Based on the experimental results the workability, strength, and durability properties of concrete made with TRA were improved in TSMA2 when compared with all other mixing approaches.

Section: Resultsmentioning

confidence: 99%

Influence of mixing approaches on strength and durability properties of treated recycled aggregate concrete

Verma

Babu

Arunachalam

2020

“…One of the solutions actively considered by the construction industry is the use of recycled aggregate (RA), obtained from demolition waste, in the preparation of recycled aggregate concrete (RAC). The advantages of using RAC is the conservation of natural resources 1,2 and gainful utilization of an environmentally-damaging waste material. Consequently, RAC will be a green and sustainable material.…”

Section: Introductionmentioning

confidence: 99%

Influence of mix composition on the properties of recycled aggregate concrete

Zaben

Maslehuddin

Al‐Amoudi

et al. 2021

There is an increasing trend towards using recycled aggregate (RA) in concrete due to the shortage of high quality natural aggregates. The use of RA in concrete results in the conservation of natural resources, protects the environment and encourages sustainable construction. Though some studies have been conducted on the use of recycled aggregate concrete (RAC), the effect of mixture composition on its properties has not been well addressed. In the reported study, the effect of mixture composition, namely cement content and water/ cement ratio and the proportion of RA on the mechanical properties of RAC was evaluated, with the intention of developing varying grades of RAC. As reported in earlier studies, the properties of RAC were generally inferior to that of normal aggregate concrete (NAC). Notwithstanding this, RAC with acceptable mechanical properties can be produced utilizing RA, for example RAC with low strength can be used in non-structural applications. The construction industry should be encouraged to use RAC in building construction; as its use will lead to technical, economic and environmental benefits. Further, the use of RAC will lead to a sustainable development of the construction industry, particularly in regions that lack good quality natural aggregates.Based on the data developed in the reported study, the following quantities of RA are recommended to produce RAC: (i) 20% to produce low strength (20--30 MPa) concrete, (ii) 40% to produce medium (30-50 MPa) concrete and high strength (more than 50 MPa) concrete. Mathematical correlations between the mechanical properties of RAC with varying mix design parameters, such as cement content and water cement ratio and the quantity of RA, are also reported. These correlations can be used to predict the properties of RAC prepared with other proportions of RA and mix design parameters.bond strength, compressive strength, mixture proportions, modulus of elasticity, morphology, recycled aggregate concrete, tensile strength Discussion on this paper must be submitted within two months of the print publication. The discussion will then be published in print, along with the authors' closure, if any, approximately nine months after the print publication.

“…On the other hand, Nazarpour and Jamali 3 studied the mechanical and freezing cycle properties of concrete, which used recycled aggregates. Wang et al 4 investigated the mechanical properties of recycled concrete, which used waste aggregates. Furthermore, Abbas et al 5 used sugarcane bagasse ash in concrete to reduce the effect of Alkali‐silica reaction.…”

Section: Introductionmentioning

confidence: 99%

Effect of super absorbent polymer on microstructural and mechanical properties of concrete blends using granite pulver

Laila

Ananthi

Roy

et al. 2020

Industrialization and urbanization has caused a serious impact on the environment due to the vast consumption of energy and eco‐unsustainable production. Therefore, scientists and engineers are placing more effort to design environmentally sustainable systems. To achieve sustainability, one potential solution is to use renewable resources to produce construction materials. The effect on various amounts of admixed super absorbent polymer (SAP) on microstructural, fresh and hardened properties of autogenous cured concrete incorporating Granite Pulver (GP) have been investigated. For this purpose, a small quantity of Portland cement was replaced by GP as 5, 10, 15, and 20%. The SAP was used at volume fractions of 0.1 to 1% to the GP‐concrete blends to counteract self‐desiccation during the hydration of concrete. Along with the GP, fly ash (FA) was also added as filler to improve the workability of GP‐concrete blends. The chemical and microstructural properties of unprocessed GP, fly ash, and cement samples along with the mechanical properties of GP‐concrete blends were investigated through different tests. A total of 627 specimens were prepared for mechanical testing of GP‐concrete blends. The GP along with the SAP increases the compressive strength and flexural strength in comparison with the control mixture by around 1.6 and 6.8% respectively, when a replacement of cement by GP up to 15% was made with an addition of 0.4% of SAP in the mixture.