Self-healing capability of asphalt concrete with carbon-based materials

The coefficient of permeability of hydraulic asphalt concrete is in the range 10−8–10−10 cm/s. Laboratory test results show that triaxial specimens in axial compression can undergo axial strains up to 18% without any significant increase in permeability until approaching the compressive strength. For temperatures between 5 and 20 °C and strain rates between 2 × 10−3%/s and 5 × 10−3%/s, conventional hydraulic asphalt concrete can tolerate 1%–3% tensile strains before cracking in direct tension tests and strains up to 3%–4% in bending. At 20 °C the tensile and bending strains at cracking are 2–4 times higher than those at 0 °C, and at −20 °C they are approximately 0.2% and 0.8%, respectively. Asphalt concrete possesses pronounced crack self-healing properties. In the experiments, the crack leakage rate dropped 1–4 orders of magnitude within a few hours and the cracked specimens regained 55% of the intact tensile strength after only 1 day of self-healing. In summary, the comprehensive series of laboratory tests documents that asphalt concrete has characteristics that make the material extremely well suited for use in impervious barriers in dams, and the test results reported herein can be of great use in barrier design.

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Addressing durability of asphalt concrete by self-healing mechanism

Bituminous Mixtures and Pavements VI ◽

10.1201/b18538-66 ◽

2015 ◽

pp. 453-461

Author(s):

R Barrasa ◽

V López ◽

C Montoliu ◽

V Ibáñez ◽

F Pedrajas ◽

...

Keyword(s):

Asphalt Concrete ◽

Self Healing

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Evaluation of self-healing of asphalt concrete through induction heating and metallic fibers

Construction and Building Materials ◽

10.1016/j.conbuildmat.2017.04.064 ◽

2017 ◽

Vol 146 ◽

pp. 66-75 ◽

Cited By ~ 21

Author(s):

Yashwanth Pamulapati ◽

Mostafa A. Elseifi ◽

Samuel B. Cooper ◽

Louay N. Mohammad ◽

Omar Elbagalati

Keyword(s):

Induction Heating ◽

Asphalt Concrete ◽

Self Healing ◽

Metallic Fibers

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Two Ways of Closing Cracks on Asphalt Concrete Pavements: Microcapsules and Induction Heating

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.417-418.573 ◽

2009 ◽

Vol 417-418 ◽

pp. 573-576 ◽

Cited By ~ 25

Author(s):

Alvaro Garcia ◽

Erik Schlangen ◽

Martin Van de Ven

Keyword(s):

Induction Heating ◽

Asphalt Concrete ◽

Healing Rate ◽

Local Heating ◽

The Other ◽

Concrete Pavements ◽

Self Healing ◽

Accumulated Damage ◽

Conductive Particles ◽

Induction Energy

It is well known that asphalt concrete is a self healing material: immediately after both faces of a crack are in contact, the diffusion of molecules from one face to the other starts. If there are no more loads, this process takes place until the crack has completely disappeared and the material has recovered its original resistance [1]. To increase this healing rate two methods are proposed. The first one is a passive self-healing mechanism. Embedded encapsulated chemicals are used in the binder. When microcracks start appearing in the binder due to the combination of ageing and accumulated damage, they break the capsules and the chemicals enter the binder by diffusion. These chemicals repair the material, decreasing the stiffness and increasing the healing rates of bitumen. The second approach makes use of an active self healing mechanism. Local heating inside the material is used to repair the binder and to improve the properties again. This is realized by adding conductive particles to the binder and using induction energy to increase the temperature. These methods are a fairly new concept in the asphalt industry.

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Addressing Durability of Asphalt Concrete by Self-healing Mechanism

Procedia - Social and Behavioral Sciences ◽

10.1016/j.sbspro.2014.12.199 ◽

2014 ◽

Vol 162 ◽

pp. 188-197 ◽

Cited By ~ 21

Author(s):

Raquel Casado Barrasa ◽

Víctor Blanco López ◽

Carlos Martín-Portugués Montoliu ◽

Verónica Contreras Ibáñez ◽

Josefina Pedrajas ◽

...

Keyword(s):

Asphalt Concrete ◽

Self Healing

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The Self-Healing Performance of Carbon-Based Nanomaterials Modified Asphalt Binders Based on Molecular Dynamics Simulations

Frontiers in Materials ◽

10.3389/fmats.2020.599551 ◽

2021 ◽

Vol 7 ◽

Author(s):

Yan Gong ◽

Jian Xu ◽

Er-hu Yan ◽

Jun-hua Cai

Keyword(s):

Healing Process ◽

Asphalt Binder ◽

Mean Square Displacement ◽

The Self ◽

Asphalt Binders ◽

Self Healing ◽

Modified Asphalt ◽

Healing Efficiency ◽

Carbon Based Nanomaterials ◽

Carbon Based

In this study, the molecular dynamics simulation was used to explore the effects of carbon-based nanomaterials as binder modifiers on self-healing capability of asphalt binder and to investigate the microscopic self-healing process of modified asphalt binders under different temperature. An asphalt average molecular structure model of PEN70 asphalt binder was constructed firstly. Further, three kinds of carbon-based nanomaterials were added at three different percentages ranging from 0.5 to 1.5% to the base binder to study their effects on the self-healing capability, including two carbon nanotubes (CNT1 and CNT2) and graphene nanoflakes. Combining with the three-dimensional (3D) microcrack model to simulate the asphalt self-healing process, the density analysis, relative concentration analysis along OZ direction, and mean square displacement analysis were performed to investigate the temperature sensitive self-healing characters. Results showed that the additions of CNTs were effective in enhancing the self-healing efficiency of the plain asphalt binder. By adding 0.5% CNT1 and 0.5% CNT2, about 652% and 230% of the mean square displacement of plain asphalt binder were enhanced at the optimal temperatures. However, the use of graphene nanoflakes as an asphalt modifier did not provide any noticeable changes on the self-healing efficiency. It can be found that the self-healing capability of the asphalt was closely related to the temperature. For base asphalt, the self-healing effect became especially high at the phase transition temperature range, while, for the modified asphalt, the enhancement of the self-healing capability at the low phase transition temperature (15°C) became negligible. In general, the optimal healing temperature range of the CNTs modified asphalt binders is determined as 45–55°C and the optimal dosage of the CNTs is about 0.5% over the total weight of the asphalt binder. Considering the effect of carbon-based nanomaterials on the self-healing properties, the recommended carbon-based nanomaterials modifier is CNT1 with the aspect ratio of 1.81.

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Influential Factors of Self-Healing Performance of Asphalt Concrete in Fracture Behavior

DEStech Transactions on Materials Science and Engineering ◽

10.12783/dtmse/ictim2017/9929 ◽

2017 ◽

Cited By ~ 2

Author(s):

Shiping Fan ◽

Hongzhou Zhu ◽

Hao Wang

Keyword(s):

Asphalt Concrete ◽

Fracture Behavior ◽

Influential Factors ◽

Self Healing

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Evaluation of Self-Healing Performance of Asphalt Concrete for Macrocracks via Microwave Heating

Journal of Materials in Civil Engineering ◽

10.1061/(asce)mt.1943-5533.0003332 ◽

2020 ◽

Vol 32 (9) ◽

pp. 04020248 ◽

Cited By ~ 1

Author(s):

Hongzhou Zhu ◽

Hai Yuan ◽

Yufeng Liu ◽

Shiping Fan ◽

Yongjie Ding

Keyword(s):

Microwave Heating ◽

Asphalt Concrete ◽

Self Healing

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MULTI-FUNCTIONAL CEMENTITIOUS COMPOSITES WITH SENSING AND HEALING CAPABILITIES

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2017.101 ◽

2017 ◽

Vol 4 (1) ◽

Author(s):

Hocine Siad ◽

Mohamed Lachemi ◽

Mustafa Sahmaran ◽

Anwar Hossain

Keyword(s):

The Self ◽

Beam Deflection ◽

Cementitious Composites ◽

Self Healing ◽

Self Monitoring ◽

Durability Properties ◽

Moisture State ◽

Compressive And Flexural Strengths ◽

Mechanical Performances ◽

Carbon Based

For smart concretes to be developed, it must be gathering high mechanical and durability properties, in addition to satisfying special characteristics such as self-monitoring of damage. This study outlines attempts to develop advanced Engineered Cementitious Composites (ECC) with combined self-sensing and self-healing capabilities. The aim is to maintain or improve the high mechanical and ductility properties of ECC, while enhancing the self-monitoring and self-healing capabilities. To assure the self-sensing functionality, carbon-based materials with different volumes were incorporated in ECC formulations. The self-healing rates of control and piezoresistive ECC’s were assessed by pre-cracking specimens up to 60% of their original flexure deformations and left those samples to heal under moist curing. The mechanical performances and ductility were evaluated based on compressive and flexural strengths, and mid-span beam deflection capacity measurements. The self-healing/self-sensing efficiency was tested by assessing the electrical resistivity (ER) variations of cylindrical specimens. Mechanical results of carbon-based ECC mixtures showed better or comparable performances than the corresponding control ECC. This study also reveals that the type of carbon-based materials and moisture state of specimens considerably influence the self-sensing/self-healing ability of ECC mixtures.

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Induction Heating and Healing Behaviors of Asphalt Concretes Doped with Different Conductive Additives

Advances in Materials Science and Engineering ◽

10.1155/2019/2190627 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Hechuan Li ◽

Jianying Yu ◽

Quantao Liu ◽

Yuanyuan Li ◽

Yaqi Wu ◽

...

Keyword(s):

High Temperature ◽

Induction Heating ◽

Asphalt Concrete ◽

Healing Rate ◽

Steel Fiber ◽

Steel Slag ◽

Rest Period ◽

Self Healing ◽

Heating Efficiency ◽

Conductive Additives

It is consensual that the self-healing property of asphalt concrete can repair the damage inside it during high temperature and rest period. In order to not affect the traffic, the rest period of asphalt pavement is very short and uncontrollable; so, it is necessary to obtain enough high temperature in a limited time to achieve higher healing efficiency of asphalt concrete. The purpose of this paper is to study the induction heating efficiency and healing behaviors of asphalt concretes doped with different conductive additives. Steel fiber, steel grit, and steel slag were added to asphalt mixtures as conductive additives to prepare induction healing asphalt concretes. The steel grit and steel slag were added to replace the aggregates of corresponding particle size by equal volume to ensure the consistency of asphalt concrete volume, which can avoid degrading the performance of asphalt concrete due to the change of porosity. The induction heating efficiency and healing rate of asphalt concrete were quantified by infrared camera and three-point bending-healing experiment, respectively. The results showed that the thermal properties of asphalt concrete changed with the addition of different conductive additives. The asphalt concrete with steel fiber had the best induction heating property. While steel slag had extremely weak induction heating speed, the better thermal insulation property of the asphalt concrete with steel slag resulted in a higher induction healing rate. It was suggested to add steel slag to induction healing asphalt concrete to improve the healing rate.

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