• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1487-1493
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• 2008

The frost heaving is related with thermal conduction rate and permeability. If the thermal conduction rate can be controlled, it is effective to prevent from frost heaving. If soil mixed with shredded tire which has relatively lower thermal conduction rate than soil, it helps preventing from frost heaving. However, in this case, the shear strength can get weak. In this study, we compared thermal conduction rate of soil and shredded tire, and test uniaxial compression strength of soil which is mixed with shredded tire and cement in different ratio.

• Geomechanics and Engineering
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• 제9권4호
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• pp.447-464
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• 2015

Millions of scrap tires are discarded annually in Turkey. The bulk of which are currently landfilled or stockpiled. These tires consume valuable landfill space or if improperly disposed, create a fire hazard and provide a prolific breeding ground for rats and mosquitoes. Used tires pose both a serious public and environmental health problem which means that economically feasible alternatives for scrap tire disposal must be found. Some of the current uses of scrap tires are tire-derived fuel, creating barrier reefs and as an asphalt additive in the form of crumb rubber. However, there is a much need for the development of additional uses for scrap tires. One development the creation of shreds from scrap tires that are coarse grained, free draining and have a low compacted density thus offering significant advantages for use as lightweight subgrade fill and backfill material. This paper reports a comprehensive laboratory study that was performed to evaluate the use of a shredded tire-sand mixture as a backfill material in trench conditions. A steel frame test tank with glass walls was created to replicate a classical trench section in field conditions. The results of the test demonstrated that shredded tires mixed with sand have a definite potential to be effectively used as backfill material for buried pipe installations.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.546-552
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• 2010

Seasonal frozen ground affects structural behavior in South Korea. Frost and heaving of seasonal frozen ground results in the critical damage of roadway, railroad, and buried pipeline. It has been widely used to substitute frost susceptible soils with granular soils. This paper presents experimental investigation on the effectiveness of soil-shredded tire and soil-expanded polystylene (EPS) mixtures to reduce frost depth and force around a buried pipeline. Experimental data such as measured temperature profile and the deformation of buried pipeline were carefully observed and provide the evidence of the effectiveness of soil mixtures.

• Advances in concrete construction
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• 제4권3호
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• pp.207-220
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• 2016

The objective of this study was to evaluate the influence of recycled materials, namely, shredded scrap tire (SST), reclaimed asphalt pavement (RAP) and class C fly ash (CFA) on compressive and tensile strength of concrete. Either SST or RAP was used as an aggregate replacement and class C fly ash (CFA) as Portland cement replacement for making concrete. A total of two types of SST and RAP, namely, chips and screenings were used for replacing coarse and fine aggregates, respectively. A total of 26 concrete mixes containing different replacement level of SST or RAP and CFA were designed. Using the mix designs, cylindrical specimens of concrete were prepared, cured in water tank, and tested for unconfined compressive strength (UCS) and indirect tensile strength (IDT) after 28 days. Experimental results showed aggregate substitution with SST decreased both UCS and IDT of concrete. On the contrary, replacement of aggregate with RAP improved UCS values. Specimens containing RAP chips resulted in concrete with higher IDT values as compared to corresponding specimens containing RAP screenings. Addition of 40% CFA was found to improve UCS values and degrade IDT values of SST containing specimens. Statistical analysis showed that IDT of SST and RAP can be estimated as approximately 13% and 12% of UCS, respectively.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.225-229
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• 2001

There are about 41% (by weight) of scrap tires were pulverized to produce rubber powder and granules in the tire recycling industry of Taiwan. However, the reuse of the by-products, steel and fiber, of the scrap tires still needs to be improved. It is difficult to remove the remaining rubber on the surface of steel or fiber. This problem reduce the availability for further reuse of steel and fiber. In addition to the improvement of magnetic, gravity separation techniques or carbonization process, using cryogenic shredding process to separate rubber and fiber (or steel) had been used as another alternative. Cryogenic shredding process for scrap tires showed many advantages, the objective of this paper is to explore the mechanisms for the cryogenic shredding process of scrap tires. Cryo-SEM is used to investigate the topographic information, in-situ, from room temperature to -195$^{\circ}C$ . One square inch shredded tire chips are prepared for SEM study. The percentage of the shrinkage of rubber is also estimated, ca. 6.7%. Mechanisms of cryogenic shredding effects on the tire chips are discussed. The proper practice of cryogenic shredding process far scrap tires is also suggested.

• Environmental Engineering Research
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• 제10권3호
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• pp.122-130
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• 2005

Gasification of carbonaceous wastes such as shredded tire, waste lubricating oil, plastics, and powdered coal initiates a single-stage reforming reactor(reformer) Without catalyst and a syngas burner. Syngas is combusted with $O_2$ gas in the syngas burner to produce $H_2O\;{and}\;CO_2$ gas with exothermic heat. Reaction products are introduced into the reforming reactor, reaction heat from syngas burner elevates the temperature of reactor above $1,200^{\circ}C$, and hydrogen gas fraction reaches 65% of the product gas output. Reactants and heat necessary for the reaction are provided through the syngas burner only. Neither $O_2$ gas nor steam is injected into the reforming reactor. Multiple syngas burners may be connected to the reforming reactor in order to increase the syngas output, and the product syngas is recycled into syngas burner.

• Geomechanics and Engineering
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• 제22권3호
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• pp.197-206
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• 2020

Reutilization of solid waste such as Tire Derived Aggregate (TDA) and mixing it with soft soil for backfill material not only reduces the required volume of backfill soil (i.e., sand-mining procedures; reinforcement), but also preserves the environment from pollution by recycling. TDA is a widely-used material that has a good track record for improving sustainable construction. This paper attempted to investigate the performance of Kaolin-TDA mixtures as a backfill material underneath a strip footing and close to a retaining wall. For this purpose, different types of TDA i.e., powdery, shredded, small-size granular (1-4 mm) and large-size granular (5-8 mm), were mixed with Kaolin at 0, 20, 40, and 60% by weight. Static surcharge load with the rate of 10 kPa per min was applied on the strip footing until the failure of footing happened. The behaviour of samples K80-G (1-4 mm) 20 and K80-G (5-8 mm) 20 were identical to that of pure Kaolin, except that the maximum footing stress had grown by roughly three times (300-310 kPa). Therefore, it can be concluded that the total flexibility of the backfill and shear strength of the strip footing have been increased by adding the TDA. The results indicate that, a significant increase in the failure vertical stress of the footing is observed at the optimum mixture content. In addition, the TDA increases the elasticity behaviour of the backfill.

• 한국도로학회논문집
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• 제18권4호
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• pp.29-35
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• 2016

PURPOSES : The new waste management policy of South Korea encourages the recycling of waste materials. One material being recycled currently is tire-derived fuel (TDF) ash. TDF is composed of shredded scrap tires and is used as fuel in power plants and industrials plants, resulting in TDF ash, which has a chemical composition similar to that of the fly ash produced from coal. The purpose of this study was to evaluate the properties of an asphalt concrete mix that used TDF ash as the mineral filler. METHODS : The properties of the asphalt concrete were evaluated for different mineral filler types and contents using various measurement techniques. The fundamental physical properties of the asphalt concrete specimens such as their gradation and antistripping characteristics were measured in accordance with the KS F 3501 standard. The Marshall stability test was performed to measure the maximum load that could be supported by the specimens. The wheel tracking test was used to evaluate the rutting resistance. To investigate the moisture susceptibility of the specimens, dynamic immersion and tensile strength ratio (TSR) measurements were performed. RESULTS : The test results showed that the asphalt concrete containing TDF ash satisfied all the criteria listed in the Guide for Production and Construction of Asphalt Mixtures (Ministry of Land, Infrastructure and Transport, South Korea). In addition, TDF ash exhibited better performance than that of portland cement. The Marshall stability of the asphalt concrete with TDF ash was higher than 7500 N. Further, its dynamic stability was also higher than that listed in the guide. The results of the dynamic water immersion and the TSR showed that TDF ash shows better moisture resistance than does portland cement. CONCLUSIONS : TDF ash can be effectively recycled by being used as a mineral filler in asphalt, as it exhibits desirable physical properties. The optimal TDF ash content in asphalt concrete based on this study was determined to be 5%. In future works, the research team will compare the characteristics of asphalt concrete as function of the mineral filler types.

• 한국화재소방학회논문지
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• 제26권6호
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• pp.99-108
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• 2012

본 연구에서는 최근 빈번히 발생하고 있는 폐타이어의 가공 및 저장상황에서의 산화열에 의한 자연발화현상을 규명하기 위해 폐타이어 분쇄물에 대한 화재 재연실험과 가공 및 저장장소에서 수거한 화재 잔존물에 대한 면밀한 성분 분석 및 발화개시온도, 무게감량, 반응열 등을 분석하였다. 이를 위해 열축적이 용이한 폐타이어 분쇄물 2.5~15 mm 범위의 파쇄된 분쇄물을 대상으로 재연실험 및 DSC 및 TGA, DTA, DTG, GC/MS를 통한 열분석을 시행하여 자연발화의 가능성에 대한 과학적인 개연성을 부여하고자 하였다. 연구결과를 살펴보면 재연실험을 통하여 관찰한 결과 48시간 저장시에 온도의 급상승($178^{\circ}C$) 및 탄화현상, 연기발생이 관찰되었다. 또한 DTA, DTG 분석한 결과 $166.15^{\circ}C$에서 최초 중량감소가 일어나는 것으로 분석되었다. 아울러 DSC 및 TGA를 이용한 폐타이어 분쇄물 1(Unburnt)의 실험결과 $180^{\circ}C$ 부근에서 열분해를 시작하는 것으로 나타나 폐타이어의 발화 개시온도는 $160{\sim}180^{\circ}C$라고 말할 수 있다. 그리고 $305^{\circ}C$에서 최초 원료 무게의 10 % 중량감소가 있었고, 원료 무게의 50 % 중량감소는 $416^{\circ}C$로 분석되었다. 또한 GC/MS와 DSC를 이용한 산화성 및 자기반응성시험에 있어서는 1,3 cyclopentnadiene 등 산화성성분이 다량 검출되었지만 표준물질과 폐타이어 분쇄물과의 열분석실험결과 기준치 이하로 분석되어 자기반응성은 없는 것으로 분석되었다. 따라서 폐타이어의 산화열에 의한 자연발화현상을 방지하기 위해서는 분쇄시 열축적이 적거나 없는 냉동파쇄방식 등의 가공공정으로 전환유도를 고려해야하며 현재 파쇄 분쇄물을 대형 마대(500 kg)로 저장하는 방식에서, 마대를 소형화하여 분쇄물을 분산 저장하는 등의 방법으로 열축적을 방지해야한다.