• Title/Summary/Keyword: Optimum Asphalt Content (OAC)

Search Result 8, Processing Time 0.026 seconds

Experimental Study for Determination of Optimum Waste Vinyl Contents in Asphalt Concrete (아스팔트 콘크리트에 적정 폐비닐 첨가량 결정에 관한 실험적 연구)

  • 김광우;김주인;이순제;최선주
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.44 no.5
    • /
    • pp.88-95
    • /
    • 2002
  • This study is a fundamental research for recycling waste vinyl (WV) in asphalt mixture for improving roadway pavement. Mix design was conducted by WV content and optimum asphalt content (OAC) was determined for dense-graded surface course mixture. Marshall stability test, indirect tensile strength (ITS) test and wheel tracking test were carried out to measure the characteristics of WV-added asphalt concretes. From the results of this study, recycling WV in asphalt mixture is possible. However, as WV content increased, melted WV clustering appeared in asphalt mixture. It could be considered that adding too much WV in asphalt mixture is not proper. The proper content of LDPE and HDPE WV was appeared to be 12% and 8%, respectively.

A Study on the Performance Evaluation and Comparison of Porous and Drainage Pavement Types (투수성 포장과 배수성 포장 구조형식의 성능평가 및 비교 연구)

  • Kim, Dowan;Jeong, Sangseom;Mun, Sungho
    • International Journal of Highway Engineering
    • /
    • v.20 no.3
    • /
    • pp.47-57
    • /
    • 2018
  • PURPOSES : The permeable pavement type has been rapidly developed for solving problems regarding traffic noise in the area of housing complex and heavy rainwater drainage in order to account for the climate change. In this regards, the objective of this study is to figure out the characteristics of pavement types. METHODS : The laboratory test for deriving optimum asphalt content (OAC) was conducted using the mixtures of the permeable asphalt surface for the pavement surface from Marshall compaction method. Based on its results, the pavement construction at the test field was conducted. After that, the site performance tests for measuring the traffic noise, strength and permeability were carried out for the relative evaluation in 2 months after the traffic opening. The specific site tests are noble close proximity method (NCPX), Light falling deflectometer test (LFWD) and the compact permeability test. RESULTS : The ordered highest values of the traffic noise level can be found such as normal dense graded asphalt, drainage and porous structure types. In the results from LFWD, the strength values of the porous and drainage asphalt types had been lower, but the strength of normal asphalt structure had relatively stayed high. CONCLUSIONS :The porous structure has been shown to perform significantly better in permeability and noise reduction than others. In addition to this study, the evaluation of the properties and the determination of the optimum thickness for the subgrade course under the porous pavement will be conducted using ground investigation technique in the further research.

Methodology for Developing HMA Mix Design Taking into Account Performance-Related Mechanistic Properties (포장성능관련 역학적 특성이 고려된 아스팔트 혼합물의 배합설계법 개발 방안)

  • Kim Boo-Il;Lee Moon-Sup;Kim Kwang-Woo
    • International Journal of Highway Engineering
    • /
    • v.8 no.1 s.27
    • /
    • pp.15-23
    • /
    • 2006
  • Criteria of the current asphalt mix design, Marshall method, includes the stability and flow which are not related with field performance of HMA mixture, together with the air void, Void filled with asphalt (VFA) and/or Void of mineral Aggregate(VMA). In addition, the limits of stability and flow are satisfied in most cases, the Optimum asphalt content (OAC) is determined based on volumetric properties, such as the air void and/or VFA and/of VMA. Therefore, many researchers have sought mechanistic properties which can replace the stability and flow, making the designed mixture having potential for better field performance. This study initiated to develope a mix design by introducing two performance-related mechanistic properties, the deformation strengh and fracture energy, in place of the stability and flow of the Marshall method. The deformation strength $(S_D)$ from the Kim Test has a high correlation with rutting property and the fracture energy(FE) from the indirect tensile test represents the fatigue cracking property of asphalt mixture. Four types of asphalt mixture were prepared for examining possibility of using the suggested mix design method in comparison with current methods. The results showed that mechanical properties were reflected in determination of OAC with this suggested mix design, unlike the existing Marshall method.

  • PDF

Evaluation of Rutting Behavior of Hot Mix Asphalt using Slag and Waste Foundry Sand as Asphalt Paving Materials (슬래그와 폐주물사를 이용한 아스팔트 혼합물의 소성변형특성에 관한 연구)

  • Lee, Kwan-Ho;Cho, Jae-Yoon;Jeon, Joo-Yong
    • 한국도로학회:학술대회논문집
    • /
    • 2002.10a
    • /
    • pp.89-92
    • /
    • 2002
  • The objective of this research is to evaluate engineering properties of recycled aggregates, slag as coarse & fine aggregate and waste foundry sand(WFS) as fine aggregate, in hot mix asphalt(HMA). In this research, soundness, gradation and particle analysis, abrasion, specific gravity and absorption test were carried out. The optimum asphalt binder content(OAC) for various HMA combinations of recycled aggregate was determined by Marshall Mix Design. The ranges determined is between 7.2% and 7.5%. Indirect tensile test, resilient modulus test, creep test were carried out for characterization of rutting behavior of various combination of HMA. Judging from the limited tests, the HMA with recycled aggregates is not as good rutting resistance as the HMA with common aggregates. After finishing the Wheel tracking test, the application or feasibility for the use of recycled aggregate as asphalt paving material will be determined.

  • PDF

Evaluation of Stripping and Rutting Properties of CRM Modified Asphalt Mixtures (CRM 개질아스팔트 혼합물의 소성변형 및 박리저항 특성)

  • Doh, Young-S.;Park, Tae-W.;Kim, Hyun-H.;Kim, Kwang-W.
    • International Journal of Highway Engineering
    • /
    • v.9 no.4
    • /
    • pp.149-158
    • /
    • 2007
  • Evaluation of the asphalt mixture modified with crumb rubber modifier(CRM) was performed to estimate possibility of using it as a paying material. OACs(optimum asphalt content) of CRM modified asphalt mixtures by dry process and wet process were determined by Marshall mix design and Wheel tracking test and moisture susceptibility test by freezing and thawing were carried out with CRM modified asphalt mixtures at OACs. The results from these tests, resistance of permanent deformation of CRM modified asphalt mixtures were superior to one of AP-5 while showing very low resistance of moisture sensitivity by freezing and thawing. This means that CRM modified asphalt mixtures are very sensitive to freezing and thawing. However, CRM modified asphalt mixture with anti-stripping material showed high improvement to resistance of moisture susceptibility by freezing and thawing. Therefore, it is recommended that when CRM mixtures were used in domestic, CRM modified asphalt mixtures should be with prevention against freezing and thawing resistance by moisture susceptibility.

  • PDF

Comparison and Evaluation of Dynamic Modulus of Hot Mix Asphalt with Different Shift Factors (전이함수 결정법에 따른 아스팔트 혼합물의 동탄성계수 비교평가)

  • Kim, Hyun-Oh;Lee, Kwan-Ho
    • International Journal of Highway Engineering
    • /
    • v.7 no.1 s.23
    • /
    • pp.49-61
    • /
    • 2005
  • The dynamic modulus of hot mix asphalt can be determined according to the different combinations of testing temperature and loading frequency. The superposition rule is adapted to get the master curve of dynamic modulus for each hot mix asphalt. There are couple of different methods to get the shift factor which is a key for making the master curve. In this paper, Arrehnius, 2002 AASHTO, and experimental method was employed to get the master curve. Evaluation of dynamic modulus for 25mm base course of hot mix asphalt with granite aggregate and two asphalt binders(AP-3 and AP-5) was carried out. Superpave Level 1 Mix Design with gyratory compactor was adopted to determine the optimum asphalt binder content(OAC) and the measured ranges of OAC were between 4.1% and 4.4%. UTM was used for laboratory test. The dynamic modulus and phase angle were determined by testing on UTM, with 5 different testing temperature(-10, 5, 20, 40, & $55^{\circ}C$) and 5 different loading frequencies(0.05, 0.1, 1, 10, 25 Hz). Using the measured dynamic modulus and phase angle, the input parameters of Sigmoidal function equation to represent the master curve were determined and these will be adopted in FEM analysis for asphalt pavements. The shift factor and activation energy for determination of master curve were calculated.

  • PDF

Predictive Equation of Dynamic Modulus for Hot Mix Asphalt with Granite Aggregates (화강암 골재를 이용한 아스팔트 혼합물의 동탄성 계수 예측방정식)

  • Lee, Kwan-Ho;Kim, Hyun-O;Jang, Min-Seok
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.26 no.3D
    • /
    • pp.425-433
    • /
    • 2006
  • The presented work provided a predictive equation for dynamic modulus of hot mix asphalt, which showed higher reliability and more simplicity. Lots of test result by UTM at laboratory has been used to develop the precise predictive equation. Evaluation of dynamic modulus for 13mm and 19mm surface course and 25mm of base course of hot mix asphalt with granite aggregate and two asphalt binders (AP-3 and AP-5) were carried out. Superpave Level 1 Mix Design with gyrator compactor was adopted to determine the optimum asphalt binder content (OAC) and the measured ranges of OAC were between 5.1% and 5.4% for surface HMA, and around 4.2% for base HMA. The dynamic modulus and phase angle were determined by testing on UTM, with 5 different testing temperature (-10, 5, 20, 40, & $55^{\circ}C$) and 5 different loading frequencies (0.05, 0.1, 1, 10, 25 Hz). Using the measured dynamic modulus and phase angle, the input parameters of Sigmoidal function equation to represent the master curve were determined and these will be adopted in FEM analysis for asphalt pavements. The effect of each parameter for equation has been compared. Due to the limitation of laboratory tests, the reliability of predictive equation for dynamic modulus is around 80%.

Evaluation of Rutting and Deformation Strength Properties of Polymer Modified SMA Mixtures (개질재 첨가에 따른 SMA 혼합물의 소성변형 및 변형강도 특성 연구)

  • Kim, Hyun-H.;Choi, Young-R.;Kim, Kwang-W.;Doh, Young-S.
    • International Journal of Highway Engineering
    • /
    • v.11 no.4
    • /
    • pp.25-31
    • /
    • 2009
  • In general, it is well known fact that the stone mastic asphalt (SMA) pavement has a high resistance against rutting. However, performance of SMA is not well measured by general method used in the laboratory. The objective of this study is to investigate an applicability of deformation strength ($S_D$) for performance estimation of SMA, and to find out the correlation between rut depth and dynamic stability, and $S_D$ of SMA. This study carried out wheel tracking test and Kim-test with optimum asphalt content (OAC) determined by mix design. The results indicated that the $S_D$ of SMA was very poorer than those of dense-graded asphalt mixtures. $S_D$ showed similar WT dynamic stability and rut-depth level. It was found that Kim-test was not reflected higher rutting resistance of SMA like as indirect tensile strength (ITS) test and Marshall stability test. Also, it was revealed that dynamic stability and rut-depth of WT had some problems to estimate rutting resistance of SMA mixtures.

  • PDF