Effect of Steel Wool and Graphite on the Electrical Conductivity and Pavement Properties of Asphalt Mixture

Induction heating consists in adding electrically conductive fibers to the asphalt mixture and heating them with an induction heating device. But still, the factors that affect the increase of temperature are not well-known. With this purpose, 25 different mixtures, with the same aggregates distribution and amount of bitumen, but with 2 different lengths, 4 different quantities, and 4 different diameters of steel wool fibers have been considered. The influence of fibers on the air void content, electrical and thermal conductivity and on the induction heating of dense asphalt concrete has been studied. It was found that steel wool fibers increase slightly the electrical and thermal conductivities of dense asphalt concrete. Finally, it has been observed that the temperature reached due to the induction heating, increases with the number of fibers in the mixture and with their diameter.

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Investigation of Moisture Sensitivity and Conductivity Properties of Inductive Asphalt Mixtures Containing Steel Wool Fiber

Advances in Civil Engineering ◽

10.1155/2020/8890814 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Seyed Mohsen Hosseinian ◽

Vahid Najafi Moghaddam Gilani ◽

Peyman Mehraban Joobani ◽

Mahyar Arabani

Keyword(s):

Electrical Conductivity ◽

Tensile Strength ◽

Electrical Resistivity ◽

Asphalt Mixtures ◽

Dynamic Resistance ◽

Moisture Resistance ◽

Steel Wool ◽

Moisture Sensitivity ◽

Optimal Amount ◽

Marshall Stability

The construction of suitable roads in rainy areas has created problems in the construction process due to the low resistance of asphalt to moisture. To solve this problem, materials are commonly used that make mixtures resistant to moisture; however, these materials may reduce the dynamic resistance of asphalt. Therefore, materials should be used that, in addition to increasing the dynamic resistance, also increase the moisture resistance of asphalt mixtures. One of these materials used in this research is steel wool fiber (SWF), which in addition to creating conductive roads also could have a significant effect on moisture resistance. In this study, the impact of 2%, 4%, 6%, 8%, and 10% SWF on the Marshall stability and moisture sensitivity of mixtures was investigated using the Marshall stability and indirect tensile strength (ITS) tests, respectively. Moreover, using SWF as a conductive fiber, the conductivity properties of asphalt mixtures were explored to find the optimal amount of electrical conductivity. The results of the Marshall stability test indicated that by increasing SWF contents, the stability of mixtures increased, compared with the base sample, and greater amounts of 6% SWF resulted in the reduction of the Marshall stability. The results of ITS showed that modification of bitumen by SWF increased ITS and tensile strength ratio (TSR) amounts of mixtures. 6% SWF was the optimal amount for enhancing the resistance of asphalt mixtures to moisture sensitivity. The results of the electrical resistivity test showed that the resistivity had three phases: high resistivity, transit, and low resistivity. Mixtures containing less than 4% SWF illustrated an insulating behavior, with electrical resistivity greater than 7.62 × 108 Ω . m . At the transit phase, the resistivity of mixtures had a sharp reduction from 7.62 × 108 Ω . m to 6.17 × 104 Ω . m . Finally, 8% SWF was known as the optimal content for the electrical conductivity of mixtures.

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Electrical conductivity of graphite modified asphalt mixture

10.1117/12.2613922 ◽

2021 ◽

Author(s):

Qi Cui ◽

Zhengang Feng ◽

Dongdong Yao ◽

Zhuang Wang ◽

Xinjun Li

Keyword(s):

Electrical Conductivity ◽

Asphalt Mixture ◽

Modified Asphalt

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Analysis on the Influence of Steel Wool Fiber on the Performance of Dense Asphalt Mixture

Material Sciences ◽

10.12677/ms.2021.114052 ◽

2021 ◽

Vol 11 (04) ◽

pp. 444-452

Author(s):

岳孙

Keyword(s):

Asphalt Mixture ◽

Wool Fiber ◽

Steel Wool

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Investigation on Deicing Property of Steel Wool Fiber-Reinforced Asphalt Mixture by Induction Heating

Advances in Materials Science and Engineering ◽

10.1155/2020/5250628 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Fa Yang ◽

Kehong Li ◽

Rui Xiong ◽

Bowen Guan ◽

Hua Zhao

Keyword(s):

Ambient Temperature ◽

Induction Heating ◽

Traffic Safety ◽

Fiber Length ◽

Asphalt Mixture ◽

Influence Factors ◽

Melting Rate ◽

Wool Fiber ◽

Output Current ◽

Steel Wool

In order to effectively solve the traffic safety problem caused by snow and ice covering the pavement in winter, steel wool fibers with different length and content were adopted in asphalt mixture to investigate its deicing performance. The deicing principle of steel wool fiber asphalt mixture by induction heating was expounded. Effects of different ice thicknesses, output currents, and ambient temperatures for asphalt mixture deicing performance were studied using an indoor-simulated induction heating deicing test. The deicing mechanism of steel wool fiber asphalt mixture by induction heating was analyzed. Grey relation entropy analysis between the average melting ice rate and the influencing factors was determined. The results show that the average ice melting rate of the asphalt mixture increases with the increase in steel wool fiber length and content. The steel wool fiber asphalt mixture heated by electromagnetic induction obtains satisfactory result. The average melting ice rate of asphalt mixture containing 6% steel wool fiber with a length of 3 mm can reach 0.50°C·s−1 at an ambient temperature of −5°C. The thinner the ice and the higher the ambient temperature, the higher the average melting ice rate. The output current is positively correlated with the average melting ice rate. The degree of influence of the five influence factors on the average melting ice rate is ranked in order as follows: fiber content, fiber length, output current, ambient temperature, and ice layer thickness.

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Microwave deicing for asphalt mixture containing steel wool fibers

Journal of Cleaner Production ◽

10.1016/j.jclepro.2018.09.223 ◽

2019 ◽

Vol 206 ◽

pp. 1110-1122 ◽

Cited By ~ 35

Author(s):

Jie Gao ◽

Haoyan Guo ◽

Xiaofeng Wang ◽

Pei Wang ◽

Yongfeng Wei ◽

...

Keyword(s):

Asphalt Mixture ◽

Steel Wool ◽

Wool Fibers

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Removing Substrate Background in TEM Microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052857 ◽

1974 ◽

Vol 32 ◽

pp. 568-569

Author(s):

John C. Russ ◽

Nicholas C. Barbi

Keyword(s):

Electrical Conductivity ◽

Rapid Growth ◽

Organic Film ◽

Absolute Concentration ◽

Background Signal ◽

X Ray ◽

Elemental Concentrations ◽

Transmission Electron ◽

Electron Microscopes ◽

The Continuum

The rapid growth of interest in attaching energy-dispersive x-ray analysis systems to transmission electron microscopes has centered largely on microanalysis of biological specimens. These are frequently either embedded in plastic or supported by an organic film, which is of great importance as regards stability under the beam since it provides thermal and electrical conductivity from the specimen to the grid.Unfortunately, the supporting medium also produces continuum x-radiation or Bremsstrahlung, which is added to the x-ray spectrum from the sample. It is not difficult to separate the characteristic peaks from the elements in the specimen from the total continuum background, but sometimes it is also necessary to separate the continuum due to the sample from that due to the support. For instance, it is possible to compute relative elemental concentrations in the sample, without standards, based on the relative net characteristic elemental intensities without regard to background; but to calculate absolute concentration, it is necessary to use the background signal itself as a measure of the total excited specimen mass.

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Macromolecular structures of biological specimens are not obscured by controlled osmium impregnation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076639 ◽

1983 ◽

Vol 41 ◽

pp. 606-607

Author(s):

Klaus-Ruediger Peters ◽

Samuel A. Green

Keyword(s):

Thin Films ◽

Electrical Conductivity ◽

Critical Point ◽

Metal Films ◽

High Magnification ◽

Osmium Impregnation ◽

Instrumental Resolution ◽

20 Nm ◽

Continuous Metal

High magnification imaging of macromolecules on metal coated biological specimens is limited only by wet preparation procedures since recently obtained instrumental resolution allows visualization of topographic structures as smal l as 1-2 nm. Details of such dimensions may be visualized if continuous metal films with a thickness of 2 nm or less are applied. Such thin films give sufficient contrast in TEM as well as in SEM (SE-I image mode). The requisite increase in electrical conductivity for SEM of biological specimens is achieved through the use of ligand mediated wet osmiuum impregnation of the specimen before critical point (CP) drying. A commonly used ligand is thiocarbohvdrazide (TCH), first introduced to TEM for en block staining of lipids and glvcomacromolecules with osmium black. Now TCH is also used for SEM. However, after ligand mediated osinification nonspecific osmium black precipitates were often found obscuring surface details with large diffuse aggregates or with dense particular deposits, 2-20 nm in size. Thus, only low magnification work was considered possible after TCH appl ication.

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