• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.401-402
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• 2011

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3888-3893
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• 2014

The number of waste tires is increasing. One effective recycling method is the pyrolysis of waste tires. Using the pyrolyzed carbon black from waste tires, the characteristics of permanent deformation for PA-13mm porous mixture were evaluated. The confining pressure of 138 kPa and deviatoric stress of 551 kPa were adopted. The testing temperature was $45^{\circ}$ and 50 gyrations of the gyratory compactor was used to simulate the medium traffic level. The mixture modified by 10% PCB showed the largest Marshall Stability of 3.41 kN. The stability of the mixtures with PCB was 50% higher than that of mixture without PCB. The limited laboratory test showed that the use of PCB in a porous pavement decreases the permanent deformation and will be an effective alternative method to reducing the permanent deformation of a porous pavement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.267-270
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• 2016

Currently, tire has a variety of information to know the information of the tire are displayed on the tire side. the market are marked with raised letters showing a variety of information relating to the tires. Such information enables people and tire related companies to distinguish between tires upon the information marked on the tires. Generally, people see the information including max press, manufacturing date, etc. Accordingly, studies on automated recognition of raised letters on tire by using image processing technology have been presented consistently. However, they lack a method for recognition of letters and improvement of the recognition. Moreover, the raised letters have been previously recognized through image processing. Further, to obtain the character recognition of a conventional side in video, it is suitably utilized the effects of lighting time of acquisition, so as part of the background and the character has a gray level values between approximately the same, is the part that is not relatively clear are many scattered. In this paper, we see the characters of the tire side using the laser sensor, recognition, was designed for character recognition of the tire side.

• Textile Coloration and Finishing
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• v.34 no.2
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• pp.109-116
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• 2022

Tire codes are made of materials such as hemp, cotton, rayon, nylon, steel, polyester, glass, and aramid are fiber reinforcement materials that go inside rubber to increase durability, driveability, and stability of vehicle tires. The reinforcement of the tire cord may construct a composite material using tires such as automobiles, trucks, aircraft, bicycles, and fibrous materials such as electric belts and hoses as reinforcement materials. Therefore, it is essential to ensure that the adhesive force between the rubber and the reinforced fiber exhibits the desired physical properties in the rubber composite material made of a rubber matrix with reinforced fibers. This study is a study on the heat treatment conditions for improving the adhesion strength of the tire cord and the reinforced fiber for tires. The core technology of the drying process is a uniform drying technology, which has a great influence on the quality of the reinforcement. Therefore, the uniform airflow distribution is determined by the geometry and operating conditions of the dryer. Therefore, this study carried out a numerical analysis of the shape of a drying nozzle for improving the performance of hot air drying in a dryer used for drying the coated reinforced fibers. In addition, the flow characteristics were examined through numerical analysis of the study on the change in the shape of the chamber affecting drying.

• Advances in concrete construction
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• v.13 no.6
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• pp.433-450
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• 2022

The conventional disposal methods of waste tires are harmful to the environment. Moreover, the recycling/reuse of waste tires in domestic and industrial applications is limited due to parent product's quality control and environmental concerns. Additionally, the recycling industry often prefers powdered rubber particles (<0.60 mm). However, the processing of waste tires yields both powdered and coarser (>0.60 mm) size fractions. Reprocessing of coarser rubber requires higher energy increasing the product cost. Therefore, the waste tire rubber (WTR) less favored by the recycling industry is encouraged for use in construction products as one of the environment-friendly disposal methods. In this study, WTR fiber >0.60 mm size fraction is collected from the industry and sorted into 0.60-1.18, 1.18-2.36-, and 2.36-4.75-mm sizes. The effects of different fiber size fractions are studied by incorporating it as fine aggregates at 10%, 20%, and 30% in the self-compacting rubberized concrete (SCRC). The experimental investigations are carried out by performing fresh and hardened state tests. As the fresh state tests, the slump-flow, T500, V-funnel, and L-box are performed. As the hardened state tests, the scanning electron microscope, compressive strength, flexural strength and split tensile strength tests are conducted. Also, the water absorption, porosity, and ultrasonic pulse velocity tests are performed to measure durability. Furthermore, SCRC's energy absorption capacity is evaluated using the falling weight impact test. The statistical significance of content and size fraction of WTR fiber on SCRC is evaluated using the analysis of variance (ANOVA). As the general conclusion, implementation of various size fraction WTR fiber as fine aggregate showed potential for producing concrete for construction applications. Thus, use of WTR fiber in concrete is suggested for safe, and feasible waste tire disposal.

• Steel and Composite Structures
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• v.46 no.5
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• pp.689-707
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• 2023

Geopolymer concrete production is interesting as it is an alternative to portland cement concrete. However, workability, setting time and strength expectations limit the sustainable application of geopolymer concrete in practice. This study aims to improve the production of geopolymer concrete to mitigate these drawbacks. The improvement in the workability and setting time were achieved with the additional use of NaOH solution whereas an increase in the strength was gained with the addition of recycled steel fibers from waste tires. In addition, the use of 25% basalt powder instead of fly ash and the addition of recycled steel fibers from waste tires improved its environmental feature. The samples with steel fiber ratios ranging between 0.5% and 5% and basalt powder of 25%, 50% and 75% were tested under both compressive and flexure forces. The compressive and flexural capacities were significantly enhanced by utilizing recycled steel fibers from waste tires. However, decreases in these capacities were detected as the basalt powder ratio increased. In general, as the waste wire ratio increased, the compressive strength gradually increased. While the compressive strength of the reference sample was 26 MPa, when the wire ratio was 5%, the compressive strength increased up to 53 MPa. With the addition of 75% basalt powder, the compressive strength decreases by 60%, but when the 3% wire ratio is reached, the compressive strength is obtained as in the reference sample. In the sample group to which 25% basalt powder was added, the flexural strength increased by 97% when the waste wire addition rate was 5%. In addition, while the energy absorption capacity was 0.66 kN in the reference sample, it increased to 12.33 kN with the addition of 5% wire. The production phase revealed that basalt powder and waste steel wire had a significant impact on the workability and setting time. Furthermore, SEM analyses were performed.

• Steel and Composite Structures
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• v.51 no.3
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• pp.337-349
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• 2024

The growing quantity of tires and building trash piling up in landfills poses a serious threat to the stability of the ecosystem. Researchers are exploring ways to reduce and use such byproducts of the construction industry in an effort to promote greener building practices. Thus, using recycled crumb rubber from scrap tires in concrete manufacturing is important for the industry's long-term viability. This study examines the proportion of waste rubber in fiber form, specifically at weight percentages of 5%, 10%, and 15%. Moreover, the study examines the shear behavior of reinforced concrete beams. A total of twelve RC beam specimens, each sized 100 mm by 150 mm by 1000 mm (w × d × L), were constructed and positioned to the test. Various mixtures were designed with different levels of scrap tire rubber content (0%, 5%, 10%, and 15%) and Stirrup Vol. Ratio (2.10, 2.80, and 3.53) in reinforced concrete beams. The findings indicate that the inclusion of scrap rubber in concrete leads to a decrease in both the mechanical characteristics and weight of the material. This is mostly attributed to the lower strength and stiffness of the rubberized concrete. Furthermore, estimations generated by a variety of design codes were examined alongside the obtained data. In order to make a comparison between the estimates provided by the different codes such as ACI 318-14, CEB-FIB and Iranian national building codes, a calculation was done to determine the ratio of the experimental shear strength to the anticipated shear strength for each code.

• Fire Science and Engineering
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• v.26 no.6
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• pp.99-108
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• 2012

These days, spontaneous ignition phenomena by oxidizing heat frequently occur in the circumstances of processing and storing waste tires. Therefore, to examine the phenomena, in this work, this researcher conducted the tests of fires of fragmented waste tires (shredded tire), closely investigated components of the fire residual materials collected in the processing and storing place, and analyzed the temperature of the starting of the ignition, weight loss, and heat of reaction. For the study, this researcher conducted fire tests with fragmented waste tires in the range of 2.5 mm to 15 mm, whose heat could be easily accumulated, and performed heat analysis through DSC and TGA, DTA, DTG, and GC/MS to give scientific probability to the possibility of spontaneous ignition. According to the tests, at the 48-hour storage, rapid increase in temperature ($178^{\circ}C$), Graphite phenomenon, smoking were observed. And the result from the DTA and DTG analysis showed that at $166.15^{\circ}C$, the minimum weight loss occurred. And, the result from the test on the waste tire analysis material 1 (Unburnt) through DSC and TGA analysis revealed that at $180^{\circ}C$ or so, thermal decomposition started. As a result, the starting temperature of ignition was considered to be $160^{\circ}C$ to $180^{\circ}C$. And, at $305^{\circ}C$, 10 % of the initial weight of the material reduced, and at $416.12^{\circ}C$, 50 % of the intial weight of the material decreased. The result from the test on oxidation and self-reaction through GC/MS and DSC analysis presented that oxidized components like 1,3 cyclopentnadiene were detected a lot. But according to the result from the heat analysis test on standard materials and fragmented waste tires, their heat value was lower than the basis value so that self-reaction was not found. Therefore, to prevent spontaneous ignition by oxidizing heat of waste tires, it is necessary to convert the conventional process into Cryogenic Process that has no or few heat accumulation at the time of fragmentation. And the current storing method in which broken and fragmented materials are stored into large burlap bags (500 kg) should be changed to the method in which they are stored into small burlap bags in order to prevent heat accumulation.

• Elastomers and Composites
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• v.34 no.2
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• pp.156-176
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• 1999

Rubber chemicals such as accelerators, antidegradants, vulcanizing agents, processing agents and retarders are very important to the production and protection of tires and rubber goods. The use of accelerators and antidegradants are evaluated in various tire components. This paper will focus on how to vulcanize tires economically and maintain the physical properties of each tire component without severe degradation due to oxygen, heat and ozone. Also, new non-nitrosoamine accelerators and non-staining antiozonants will be discussed. Lastly, the future requirements of antidegradants and accelerators in the tire industry will be reviewed. Tires have been vulcanized with Sulfenamides as primary accelerators and either Guamdine's or Thiurams as secondary accelerators to achieve proper properties at service conditions. However, interior components such as the carcass can be vulcanized with Thiazoles as a primary accelerator to cure faster than the external components. Using the combination of Sulfenamide with secondary accelerators in a tire tread compound and the combination of a Thiazole and Guanidine in a carcass compound will be presented with performance data. Uniroyal Chemical and another Rubber Chemical Manufacturer have developed, "Tetrabenzyl Thiuram Disulfide," (TBzTD) as a non-Nitrosoamine accelerator, which could replace Nitrosoamine generating Thiurams. This new accelerator has been evaluated in a tread compound as a secondary accelerator. Also, Flexsys has developed N-t-butyl-2-benzothiazole Sulfenamide (TBSI) as a non-Nitrosoamine accelerator which could replace 2-(Morpholinothio) -benzothiazole (MBS), a scorch delayed Sulfendamide accelerator. TBSI has been evaluated in a Natural Rubber (NR) belt skim compound vs. MBS. An optimum low rolling resistant cure system has been developed in a NR tread with Dithiomorpholine (DTDM). Also, future requirements for developing accelerators will be discussed such as the replacement of DTDM and other stable crosslink systems. Antidegradants are divided into two different types for use in tire compounds. Internal tire compounds such as apex, carcass, liner, wire breaker, cushion, base tread and bead compounds are protected by antioxidants against degradation from oxygen and heat due to mechanical shear. The external components such as sidewall, chafer and cap tread com-pounds are protected from ozone by antiozonants and waxes. Various kinds of staining and non-staining antioxidants have been evaluated in a tire carcass compound. Also, various para-phenylene diamine antiozonants have been evaluated in a tire sidewall compound to achieve the improved lifetime of the tire. New non-staining antiozonants such as 2, 4, 6-tris-(N-1, 4-dimethylpentyl-p-phenylene diamine) 1, 3, 5 Trizine (D-37) and un-saturated Acetal (AFS) will be discussed in the tire sidewall to achieve better appearance. The future requirements of antidegradants will be presented to improve tire performance such as durability, better appearance and longer lasting tires.

• Elastomers and Composites
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• v.52 no.3
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• pp.167-172
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• 2017

Ultra-high performance (UHP) tires, for which demand has recently surged, are subject to severe strain conditions due to the low aspect ratio of their sidewalls. It is important to ensure sidewall material durability, since a sudden tire sidewall breakage during vehicle operation is likely to cause a major accident. In the automotive application of rubber parts, cracking is defined as a failure because when cracks occur, the mechanical properties of rubber change. According to Mars, Andre et al., strain and strain energy density (SED) are mainly used as a failure parameters and the SED is generally used as a fatigue damage parameter. In this study, the fatigue life curves of sidewall rubber of tires were determined by using the SED as fatigue damage parameter while the effect of aging on fatigue life was evaluated after obtaining the SED-Nf curves according to aging condition.