Effect of FORTA-FI Fibers on the Rutting Potential, Dynamic Modulus, Flow Number, and Fatigue of Asphalt Concrete

The article presents the results of dynamic modulus tests carried on the asphalt concrete (AC16W). The sinusoidal load was applied to the samples in accordance with DTC-CY method. The neat bituminous binder (penetration grade 35/50) was modified by means two synthetic waxes, coming from the Fischer-Tropsch raction, with various molecular weights and softening point temperature results (hard and softer). The relaxation phenomenon in terms of changes in complex modulus and phase angle was evaluated using the modified Huet-Sayegh (2S2P1D). Estimated model parameters pointed out that the addition of the synthetic wax with the high (hard wax) and the low (softer wax) molecular weight raised the stiffness of the bituminous binder in relation to the reference bitumen 35/50. The application of the modified Huet-Sayegh model showed that the presence of the synthetic wax in the bitumen significantly affected the stiffness modulus of considered asphalt concretes. Basing analysis on Cole-Cole diagram it was found significant differences in the viscoelastic behaviour between the reference asphalt concrete and the asphalt concretes with synthetic waxes. In contrast, there were no significant differences between viscoelastic properties of tested asphalt concretes modified, used in the experiment, synthetic waxes. Furthermore, the sensitivity to the loading time of asphalt concretes containing both synthetic waxes was marginal.

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Evaluation of Fatigue Life of Asphalt Concrete From Dynamic Modulus Test

Volume 10: Micro- and Nano-Systems Engineering and Packaging ◽

10.1115/imece2017-71813 ◽

2017 ◽

Cited By ~ 1

Author(s):

Md Mehedi Hasan ◽

Hasan M. Faisal ◽

Biswajit K. Bairgi ◽

A. S. M. Rahman ◽

Rafiqul Tarefder

Keyword(s):

Fatigue Life ◽

Asphalt Concrete ◽

Dynamic Modulus ◽

Performance Testing ◽

Fatigue Performance ◽

Construction Sites ◽

Reclaimed Asphalt ◽

Wide Range ◽

Dynamic Modulus Test ◽

Study Laboratory

Asphalt concrete’s dynamic modulus (|E*|) is one of the key input parameters for structural design of flexible pavement according to the Mechanistic Empirical Pavement Design Guide (MEPDG). Till this day, pavement industry uses |E*| to predict pavement performance whether the material is hot mix asphalt (HMA) or warm mx asphalt or Reclaimed Asphalt Pavement (RAP) mixed HMA. However, it is necessary to investigate the correlation of |E*| with laboratory performance testing. In this study, laboratory dynamic modulus test was conducted on four different asphalt concrete mixtures collected from different construction sites in the state of New Mexico and mastercurves were obtained to evaluate dynamic modulus (|E*|) for a wide range of frequency. In addition, fatigue performance of these mixtures was predicted from the mastercurves and compared with the laboratory fatigue performance testing. Fatigue performance of these mixtures was evaluated from the four point beam fatigue test. The laboratory results show a good agreement with the predicted value from mastercurves. It is also observed from this study that the fatigue life of the asphalt concrete materials decreases with increase in |E*| value.

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