Shrinkage of heavyweight magnetite concrete with and without fly ash

Yang, Keun–Hyeok; Mun, Ju–Hyun; Shim, Hyunju

doi:10.1016/j.conbuildmat.2013.05.034

Cited by 19 publications

(18 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, this will not be achievable in this study due to the flowability requirements of self-compacting concrete [15]. The ordinary sand and fly ash are often suggested as replacements for heavyweight fine aggregate and cement in mixing design of HWC, respectively, since these substitutions are effective in avoiding segregation by adjusting the HWA’s grading and minimizing temperature cracks by lowering heat generated during the hydration process [16].…”

Section: Literature Reviewmentioning

confidence: 99%

Development of Heavyweight Self-Compacting Concrete and Ambient-Cured Heavyweight Geopolymer Concrete Using Magnetite Aggregates

et al. 2019

View full text Add to dashboard Cite

Heavyweight self-compacting concrete (HWSCC) and heavyweight geopolymer concrete (HWGC) are new types of concrete that integrate the advantages of heavyweight concrete (HWC) with self-compacting concrete (SCC) and geopolymer concrete (GC), respectively. The replacement of natural coarse aggregates with magnetite aggregates in control SCC and control GC at volume ratios of 50%, 75%, and 100% was considered in this study to obtain heavyweight concrete classifications, according to British standards, which provide proper protection from sources that emit harmful radiations in medical and nuclear industries and may also be used in many offshore structures. The main aim of this study is to examine the fresh and mechanical properties of both types of mixes. The experimental program investigates the fresh properties of HWSCC and HWGC through the slump flow test. However, J-ring tests were only conducted for HWSCC mixes to ensure the flow requirements in order to achieve self-compacting properties. Moreover, the mechanical properties of both type of mixes were investigated after 7 and 28 days curing at an ambient temperature. The standard 100 × 200 mm cylinders were subjected to compressive and tensile tests. Furthermore, the flexural strength were examined by testing 450 × 100 × 100 mm prisms under four-point loading. The flexural load-displacement relationship for all mixes were also investigated. The results indicated that the maximum compressive strength of 53.54 MPa was achieved by using the control SCC mix after 28 days. However, in HWGC mixes, the maximum compressive strength of 31.31 MPa was achieved by 25% magnetite replacement samples. The overall result shows the strength of HWSCC decreases by increasing magnetite aggregate proportions, while, in HWGC mixes, the compressive strength increased with 50% magnetite replacement followed by a decrease in strength by 75% and 100% magnetite replacements. The maximum densities of 2901 and 2896 kg/m3 were obtained by 100% magnetite replacements in HWSCC and HWGC, respectively.

show abstract

Section: Literature Reviewmentioning

confidence: 99%

Development of Heavyweight Self-Compacting Concrete and Ambient-Cured Heavyweight Geopolymer Concrete Using Magnetite Aggregates

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The autogenous shrinkage strains of HPC is typically characterised by an exponential distribution that has both acceleratory and slow flow periods for the increasing rate of shrinkage with age, as shown in Figure 10 . Thus, the autogenous shrinkage strain (

) of concrete at a given time ( t ) is commonly expressed by the product of the ultimate autogenous shrinkage strain (

) and an exponential time function (

), as expressed in the following form [ 32 , 33 ]:

…”

Section: Modelling the Autogenous Shrinkage Of Hpc Containing Zeolmentioning

confidence: 99%

“…Thus,

is determined from

when the experimental record is given at

. Overall,

can be calculated from the following equation [ 33 ]:

…”

Section: Modelling the Autogenous Shrinkage Of Hpc Containing Zeolmentioning

confidence: 99%

Effect of Zeolite on Shrinkage and Crack Resistance of High-Performance Cement-Based Concrete

et al. 2020

Self Cite

View full text Add to dashboard Cite

This study examined the effectiveness of zeolite addition to reduce the autogenous shrinkage of high-performance cement-based concrete (HPC). The zeolites were replaced up to 15% of the cement content by weight and their mean particle size varied from 5.6 to 16.7 µm. To evaluate the crack resistance of HPC containing zeolites, the ring tests and internal relative humidity measurements were performed at different ages. The compressive strengths were determined at 3, 7, 28 and 90 days of curing. Test results confirmed that the addition of zeolite was promising and favourable in enhancing the compressive strength, crack resistance and reducing the autogenous shrinkage of HPC due to synergistic pozzolanic and internal curing effects. The autogenous shrinkage tended to decrease with the increase in zeolite content and its particle size. In addition, the extent of the autogenous shrinkage development at the early ages decreased with higher zeolite content replaced. Furthermore, to predict the autogenous shrinkage of HPC containing zeolite, an improved model has been proposed, in which the conventional ultimate autogenous shrinkage strain and time function were modified by introducing new parameters accounting for the zeolite content and its particle size. It appeared that the proposed model was able to capture the autogenous shrinkage behaviour of HPC with or without zeolite, while the fib 2010 model underestimated the autogenous shrinkage of HPC containing less than 10% zeolite replacement.

show abstract

“…It has been shown in previous literature that the shielding capacity of walls has a direct relationship with the density of the concrete and its thickness. Hence HWC radiation‐shielding properties can be improved by increasing either of these variables 10 . It can be deduced from this information that HSHWC is a viable option for a higher shielding requirement where space is limited.…”

Section: Literature Reviewmentioning

confidence: 99%

“…Yang et al 10 examined 15 heavyweight magnetite concrete mixes with the various substitution levels of conventional sand and fly ash, based on the practical mixing conditions, in order to explore the correlation between the aggregate particle properties and the concrete shrinkage. They found that it is beneficial to add up to 15% fly ash as a replacement before occurring a decrease in strain capacity and other measurable strength properties.…”

Section: Literature Reviewmentioning

confidence: 99%

Development and analysis of highly workable high‐strength heavyweight concrete using magnetite aggregates

Aslani

Lesslie

Hamidi

2020

Structural Concrete

View full text Add to dashboard Cite

Heavyweight concrete (HWC) is produced by replacing natural aggregates in a concrete mix design with heavyweight aggregates of a higher specific gravity. HWC is mainly used for the prevention of leakage from radioactive containing structures and is hence primarily used in the medical and nuclear energy industries where this property is of particular benefit and importance. Also, high‐strength concrete (HSC) has been increasingly employed in both civil structures, such as high rise buildings and bridges and defense applications. This study makes attempt to develop and evaluate different concrete mixes, which are considered as high‐strength, heavyweight and highly workable in nature. Such mixes use magnetite as the primary aggregate. The three‐mentioned properties of these concrete types have been thoroughly investigated individually; however, there is a limited numbers of literature on the analysis of mix designs dealing with the three‐mentioned properties simultaneously, in which the water/cement ratio variation, and/or variation of the magnetite content have been assessed. In this study, nine highly workable high‐strength HWC mixes have been developed and fresh and hardened properties are discussed. The overall result indicates that the developed mixes satisfied the required high‐strength, heavyweight and highly workable criteria, as well as, compressive strength would increase by increasing the heavyweight aggregate content.

show abstract

Shrinkage of heavyweight magnetite concrete with and without fly ash

Cited by 19 publications

References 7 publications

Development of Heavyweight Self-Compacting Concrete and Ambient-Cured Heavyweight Geopolymer Concrete Using Magnetite Aggregates

Development of Heavyweight Self-Compacting Concrete and Ambient-Cured Heavyweight Geopolymer Concrete Using Magnetite Aggregates

Effect of Zeolite on Shrinkage and Crack Resistance of High-Performance Cement-Based Concrete

Development and analysis of highly workable high‐strength heavyweight concrete using magnetite aggregates

Contact Info

Product

Resources

About