• 한국도로학회논문집
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• 제18권1호
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• pp.57-62
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• 2016

PURPOSES : Reflection cracking has been one of the major causes of distress when asphalt pavement is laid on top of concrete pavement. This study evaluated the reflection cracking resistance of asphalt mixtures reinforced with asphalt embedded glass fiber and carbon fiber using a Texas Transportation Institute (TTI) overlay tester. METHODS : Different asphalt mixtures such as polymer-modified mastic asphalt (PSMA) and a dense graded asphalt mixture were reinforced with asphalt-embedded carbon fiber and glass fiber. For comparison purposes, two PSMA asphalt mixtures and one dense graded asphalt mixture were evaluated without fiber reinforcement. Two different overlay test modes, the repeated overlay test (R-OT) and monotonic overlay test (M-OT), were used to evaluate the reflection cracking resistance of asphalt mixtures at $0^{\circ}C$. In the R-OT test, the number of repeated load when the specimen failed was obtained. In the M-OT test, the tensile strength at the peak load and tensile strain were obtained. RESULTS : As expected, the fiber-reinforced asphalt mixture showed a higher reflection cracking resistance than the conventional nonreinforced asphalt mixtures based on the R-OT test and M-OT test. The dense graded asphalt mixture showed the least reflection cracking resistance and less resistance than the PSMA. CONCLUSIONS : The TTI overlay tester could be used to differentiate the reflection cracking resistance values of asphalt mixtures. Based on the R-OT and M-OT results, the carbon-fiber-reinforced asphalt mixture showed the highest reflection cracking resistance among the nonreinforced asphalt mixtures and glass-fiber-reinforced asphalt mixture.

• 한국도로학회논문집
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• 제20권4호
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• pp.27-34
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• 2018

PURPOSES : The objective of this study is to evaluate the physical properties of recycled asphalt mixtures reinforced with glass fiber. METHODS : Firstly, mixing design was conducted on recycled asphalt mixture for use of 50% recycled aggregate. Various laboratory tests were performed on four types of recycled asphalt mixtures with different glass fiber content to evaluate the physical properties. The laboratory tests include indirect tensile strength test, dynamic modulus test, Hamburg wheel tracking test and tensile-strength ratio to evaluate cracks, rutting and moisture resistance of mixtures. RESULTS : The indirect tensile strength of fiber reinforced glass increased about 139.4%. As a result of comparing the master curves obtained by the dynamic modulus test, the elasticity was low in the low temperature region and high in the high temperature region when the glass fiber was reinforced. The glass fiber contents of PEGS 0.3%, Micro PPGF 0.1% and Macro PPGF 0.3% showed the highest moisture resistance and rutting resistance. CONCLUSIONS : The test results show that use of glass fiber reinforcement can increase the resistance to cracking, rutting, and moisture damage of asphalt mixtures. It is also necessary to validate the long-term performance of recycled asphalt mixtures with glass fiber using full scale pavement testing and field trial construction.

• 한국도로학회논문집
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• 제19권5호
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• pp.43-48
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• 2017

PURPOSES : The purpose of this study is to verify the effects of fiber grid reinforcement on the thickness reduction of asphalt pavement. Test sections were constructed on the national highway to evaluate the structural capacity of asphalt pavement with the reinforced fiber grid and normal asphalt pavement. METHODS : Falling Weight Deflectometer (FWD) tests were performed to measure the structural capacity of test sections. The loads of the FWD test are 4.1 ton, 8.0 ton, 10.0 ton, and loaded twice, respectively. The test sections consist of a reference asphalt pavement section, an asphalt pavement section reduced with a 5-cm base layer thickness, and a fiber grid reinforced asphalt pavement section reduced with a 5-cm base layer thickness. In addition, strain data was collected using strain gauges installed in the test sections. RESULTS : The results of the FWD tests showed that the deflections of the pavement section reinforced with the fiber grid was reduced by about 14% compared with that of the reference asphalt pavement section. The strain at the bottom of the asphalt surface layer of the pavement section reduced to a 5-cm base thickness and reinforced with a fiber grid was similar to that at the bottom of the asphalt layer of the reference asphalt pavement. CONCLUSIONS : The results of the FWD and strain tests showed the possibility of the pavement thickness reduction by reinforcement with a fiber grid.

• 한국방재학회 논문집
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• 제2권3호
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• pp.79-88
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• 2002

본 연구는 산업폐기물인 D사의 K 섬유를 사용하여 아스팔트 콘크리트 혼합물의 피로파괴에 대한 저항성 향상의 증진가능성을 평가하고자 수행되었다. 본 연구에서는 MTS사의 CLSS (Closed-Loop Servohydraulic System)와 미국 표준시험법인 ASTM D 4123에 따라 MTS사가 개발한 시험장치를 사용하여 피로시험을 수행하였다. 본 연구 결과에 의하면 적정 섬유첨가량은 전체 혼합물 중량기준 약 0.2%의 길이 8mm 섬유가 가장 우수한 성능을 발휘함을 보였고, 이 때의 적정 아스팔트 함량은 전체 혼합물 중량기준 5.5%로 나타났다. 폐섬유를 재활용하여 생산된 섬유보강 아스팔트 혼합물이 기존의 밀입도 20 아스팔트 혼합물보다 피로파괴에 대한 저항성면에서 월등히 우수한 것으로 나타났다. 또한, 섬유보강 아스팔트 혼합물의 회복 탄성계수값은 일반 밀입도20 아스팔트 혼합물보다 약 $1.15{\sim}1.18$배 높게 평가되었다.

• 한국도로학회논문집
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• 제19권3호
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• pp.31-43
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• 2017

PURPOSES : The objective of this study is to verify the effect of fiber grid reinforcement on the long-term performance of asphalt pavement overlaid on old concrete pavement by performing field investigation, laboratory test, and finite element analysis. METHODS : The reflection cracking, roughness, and rutting of fiber grid reinforced overlay sections and ordinary overlay sections were compared. Cores were obtained from both the fiber grid reinforced and ordinary sections to measure bonding shear strength between the asphalt intermediate and asphalt overlay layers. Fracture energy, displacement after yield, shear stiffnesses of the cores were also obtained by analyzing the test results. Finite element analysis was performed using the test results to validate the effect of the fiber grid reinforcement on long-term performance of asphalt pavement overlaid on the old concrete pavement. The fatigue cracking and reflection-cracking were predicted for three cases: 1) fiber grid was not used; 2) glass fiber grid was used; 3) carbon fiber grid was used. RESULTS : The reflection-cracking ratio of fiber grid reinforced sections was much smaller than that of ordinary sections. The fiber grid reinforcement also showed reduction effect on rutting while that on roughness was not clear. The reflection-cracking was not affected by traffic volume but by slab deformation and joint movement caused by temperature variation. The bonding shear strength of the fiber grid reinforced sections was larger than that of the ordinary sections. The fracture energy, displacement after yield, and shear stiffnesses of the cores of the fiber grid reinforced sections were also larger than those of the ordinary sections. Finite element analysis results showed that fatigue cracking of glass or carbon fiber grid reinforced pavement was much smaller than that of ordinary pavement. Carbon fiber grid reinforcement showed larger effect in elongating the fatigue life of the ordinary overlay pavement compared to glass fiber grid reinforcement. The binder type of the overlay layer also affected the fatigue life. The fiber grid reinforcement resisted reflection-cracking and the carbon fiber grid showed the greater effect. CONCLUSIONS :The results of field investigation, laboratory test, and finite element analysis showed that the fiber grid reinforcement had a better effect on improving long-term performance of asphalt pavement overlaid on the old concrete pavement.

• 한국지반공학회논문집
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• 제20권1호
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• pp.13-19
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• 2004

국내 아스팔트 포장의 주요파손은 피로균열, 반사균열, 온도균열, 소성변형 등이 발생하고 있다. 이러한 아스팔트포장의 파손을 최소화하기 위해 기존의 아스팔트 포장 층에 포장섬유를 포설, 보강하는 기법이 적용될 수도 있다. 본 연구에서는 포장섬유 아스팔트 포장 시스템을 체계적으로 정립하기 위해 유리섬유 시트로 보강한 아스팔트 포장층을 대상으로 실내시험을 실시하였다. 실내시험은 포장섬유 보강 아스팔트 포장의 균열저항성과 소성변형을 평가하기 위해 휠트래킹 시험과 균열저항성 시험을 수행하여 포장섬유 아스팔트 포장의 소성변형 및 균열 저항성을 분석하였다.

• 한국도로학회논문집
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• 제10권4호
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• pp.281-292
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• 2008

국내 LTPP(Long Term Pavement Performance) 연구에서 섬유보강 아스팔트 포장의 성능을 평가하기 위해, 국도 1호선 구간에 일반 아스팔트 포장과 섬유보강 아스팔트 포장을 각각 시공하였으며, 각각의 단면에 포장체 구조적 거동을 측정할 수 있는 계측센서를 매설하였다. 본 연구에서는 국내 LTPP구간에서 수행된 차량재하시험과 FWD시험의 결과를 바탕으로 섬유보강 아스팔트 포장의 구조적 성능을 평가하였다. 본 연구결과, 차량재하시험에서 섬유보강재를 사용할 경우 표층하단부의 변형률이 크게 저감되는 것을 확인하였다. 또한 일반 아스팔트 포장보다 응력중립축이 상승하여 일반 아스팔트포장은 중간층 하단에서 압축변형이 발생하는 반면에, 섬유보강 아스팔트포장은 중간층 하단에서 인장변형이 발생하였다. 반면 기층 하단부에서의 인장변형률은 두 포장형식 모두 큰 차이를 나타내지 않았다. FWD 시험에서도 섬유보강재를 사용할 경우 약 24% 정도 표면 처짐 량이 저감되는 것을 확인하였다. 이와 같은 결과를 종합하여 볼 때, 섬유보강 아스팔트 포장이 소성변형에 대한 저항성을 증진시킬 수 있다고 판단되며, 향후에 포장상태조사를 통해 장기포장공용성에 대한 연구가 수반되어야 할 것이다.

• 한국도로학회논문집
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• 제14권4호
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• pp.29-36
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• 2012

PURPOSES : Plastic deformation is frequently made in intersection asphalt pavement at its early age due to deceleration and stoppage of vehicles. This study has been performed to provide a mechanistic basis for reasonable selection of paving method to minimize the plastic deformation at intersection. METHODS : Pavement layer, temperature, traffic volume of the intersections managed by the Daejeon Regional Construction and Management Administration were collected to calculate asphalt dynamic modulus with pavement depth by using a prediction equation suggested by the Korean pavement design guide. Performance of ordinary dense-graded asphalt pavement, polymer modified asphalt pavement, and fiber reinforced asphalt pavement was analyzed by finite element method and the results were used in a performance model to predict the plastic deformation. RESULTS : In aspect of performance, the three paving methods were usable under low traffic while the fiber reinforced asphalt pavement was the most suitable under heavy traffic. CONCLUSIONS : Reasonable paving method suitable for traffic characteristics in the intersection might be decided by considering economic feasibility.

• 한국지반신소재학회논문집
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• 제1권1호
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• pp.53-61
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• 2002

최근 들어 토목섬유를 이용한 아스팔트 포장에 관한 많은 실내실험 및 현장 시험 시공연구가 수행되어 왔으나, 아직까지도 토목섬유 보강 아스팔트 포장 시스템의 경제성에 대한 합리적이고 체계적인 분석이 제시되지 못하고 있는 실정이다. 따라서 본 연구에서는 최근 경제성 분석기법으로 활용되고 있는 수명주기비용분석(LCCA; Life Cycle Cost Analysis)을 적용하여 유리섬유 시트 보강 아스팔트 포장에 대한 중차량 비율을 고려한 교통 특성에 따른 경제성 분석을 시도하였으며, 이를 통하여 기존 문헌에서 제시된 실험 결과를 경제성 분석 모텔에 적용하여 유리섬유 시트 보강 및 교통 특성에 따른 경제성을 검토하였다.

• 한국도로학회논문집
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• 제11권4호
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• pp.153-160
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• 2009

본 연구에서는 국내 LTPP 구간에서 수행된 FWD 시험의 결과를 바탕으로 섬유보강, 폴리머 개질, 일반 아스팔트 포장의 구조적 성능을 비교 평가하였다. FWD 시험 결과, 표층 하단부의 인장변형량이 섬유보강 아스팔트는 29%, 폴리머 개질 아스팔트는 21% 저감되는 것을 확인하였다. 또한 FWD 처짐량을 역산하여 각 층의 탄성계수를 추정한 후 이를 바탕으로 AASHTO 설계방법, 구조적 해석 방법 및 생애주기비용분석을 통해 섬유보강 및 폴리머 개질 아스팔트 포장의 비용 효과를 분석하였다. 분석 결과, 섬유보강은 약 5cm, 폴리머 개질은 약 3cm의 아스팔트 층 두께 감소 효과를 보여주었다. 그러나 섬유보강 및 폴리머 개질 아스팔트의 고가격으로 인하여 전체 시공재료비는 일반 아스팔트 포장에 비해 상승하는 결과를 보여주었다. 생애주기비용 결과는 초기 공사비는 섬유보강 및 폴리머 개질 아스팔트 포장이 높지만, 유지관리비용 및 사용자비용은 감소하는 것으로 나타났다.