On entrained pore size distribution of foamed concrete

Hilal, Ameer A.; Thom, Nick; Dawson, Andrew

doi:10.1016/j.conbuildmat.2014.09.117

Cited by 128 publications

(28 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As stated in (Hilal et al 2015b), this matrix microstructure improvement can also be deduced from the difference between the vacuum saturation po- • Secondly, due to reduced size and connectivity of voids, by preventing their merging and producing a narrow void size distribution, inclusion of these additives achieved higher strength leading to brittle behaviour. In opposition to this, for all mixes, higher foam volume resulted in a greater degree of void merging, leading to large irregular voids which resulted in a wide distribution of void sizes and lower strength (Hilal et al 2015a); as a result a more ductile behaviour was noticed, i. e. the lower the density the higher the ductility. Compared to mixes without LWA, for a given density, inclusion of LWA leads to improved ductility with and without the other additives (i.e.…”

Section: Fracture Energy and Ductilitymentioning

confidence: 90%

Failure Mechanism of Foamed Concrete Made with/without Additives and Lightweight Aggregate

Hilal

Thom

Dawson

2016

ACT

Self Cite

View full text Add to dashboard Cite

It has been reported that owing to a densification of the internal structure of concrete, adding mineral admixtures leads to a more brittle behaviour. Therefore, with the intention of modifying (increasing the strength of) foamed concrete to make it suitable for structural purposes by means of admixtures and lightweight aggregate addition, the effect of these additions on the failure mechanism under compressive and tensile loading using different techniques is evaluated and discussed in this paper. Eight different mixes, made using a pre-formed foam, were investigated with varying density (different foam volumes), nominally 1300, 1600 and 1900 kg/m 3 , without/with admixtures (silica fume, fly ash and superplasticizer) and lightweight aggregate. The Digital Image Correlation (DIC) technique was adopted to measure the deformations and strains on the surface of a specimen under uniaxial compressive load. Meanwhile, a Video Gauge technique was used to measure the horizontal deformation of discs during a splitting tensile test. From elasticity, fracture and fractal points of view, it was found that, for the same density, brittleness increases with many of the additives while it reduces with inclusion of lightweight aggregate. However, for all mixes, the lower the density (higher added foam volume), the higher the ductility.

show abstract

Section: Fracture Energy and Ductilitymentioning

confidence: 90%

Failure Mechanism of Foamed Concrete Made with/without Additives and Lightweight Aggregate

Hilal

Thom

Dawson

2016

ACT

Self Cite

View full text Add to dashboard Cite

show abstract

“…Paste consistency could be adjusted by adding a water reducer. Meanwhile, Hilal et al [19,20] analyzed the coupling relationship between bubbles under natural and stress states during foam concrete coagulation and pores in hardened foam concrete. The scholars found that the bubbles combined during the stirring and coagulation of foam concrete, thereby expanding the pore diameter distribution of the foam concrete and reducing the foam concrete's strength.…”

Section: Introductionmentioning

confidence: 99%

Effect of Water-Cement Ratio on Pore Structure and Strength of Foam Concrete

Liu

Zhao

et al. 2016

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

Foam concrete with different dry densities (400, 500, 600, 700, and 800 kg/m3) was prepared from ordinary Portland cement (P.O.42.5R) and vegetable protein foaming agent by adjusting the water-cement ratio through the physical foaming method. The performance of the cement paste adopted, as well as the structure and distribution of air pores, was characterized by a rheometer, scanning electron microscope, vacuum water saturation instrument, and image analysis software. Effects of the water-cement ratio on the relative viscosity of the cement paste, as well as pore structure and strength of the hardened foam concrete, were discussed. Results showed that water-cement ratio can influence the size, distribution, and connectivity of pores in foam concrete. The compressive strength of the foam concrete showed an inverted V-shaped variation law with the increase in water-cement ratio.

show abstract

“…Like other types of concrete [9][10][11], the material properties of foamed concrete are significantly affected by the pore characteristics, and many studies have been reported about the pore characteristics of foamed concrete over the past few years. Kearsley and Wainwright [12] examined the porosity effect on the mechanical property of foamed concrete, and Hilal et al [13] investigated the size distribution of the entrained pores in foamed concrete. Wei et al [14,15] characterized and simulated the microstructure of foamed concrete.…”

Section: Introductionmentioning

confidence: 99%

Pore Characteristics and Their Effects on the Material Properties of Foamed Concrete Evaluated Using Micro-CT Images and Numerical Approaches

et al. 2017

View full text Add to dashboard Cite

Foamed concrete contains numerous pores inside the material, and these pores are a significant factor determining the material characteristics. In particular, the pore distribution characteristics of foamed concrete significantly affect its thermal and mechanical properties. Therefore, an appropriate investigation is necessary for a more detailed understanding of foamed concrete. Here, a set of foamed concrete samples with different densities is used in order to investigate the density effects on the pore characteristics, as well as the physical properties of the materials. The pore distribution characteristics of these samples are investigated using an X-ray micro-computed tomography (micro-CT) imaging technique with probabilistic and quantitative methods. Using these methods, the anisotropy, the pore circularity factor and the relative density of cell thickness are examined. The thermal (thermal conductivity) and mechanical (directional modulus and strength) properties of each foamed specimen are computed using numerical simulations and compared with experimental results. From the obtained results, the effects of the pore sizes and shapes on the local and global properties of the foamed concrete are examined for developing advanced foamed concrete with lower thermal conductivity by minimizing the strength reduction.

show abstract

On entrained pore size distribution of foamed concrete

Cited by 128 publications

References 9 publications

Failure Mechanism of Foamed Concrete Made with/without Additives and Lightweight Aggregate

Failure Mechanism of Foamed Concrete Made with/without Additives and Lightweight Aggregate

Effect of Water-Cement Ratio on Pore Structure and Strength of Foam Concrete

Pore Characteristics and Their Effects on the Material Properties of Foamed Concrete Evaluated Using Micro-CT Images and Numerical Approaches

Contact Info

Product

Resources

About