The National Academies Press

Currently Skimming:

Pages 97-118

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 97... ... B-1 Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 Introduction Fatigue cracking occurs in asphalt pavements as the result of repeated bending from traffic loads. This bending results in tensile strains in the asphalt layer, which result in the formation of cracks, either at the bottom of the layer for thin pavements (classical bottom-up fatigue) Read the entire page →
From page 98... ... B-2 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures The failure point for the BBF was initially defined as the number of cycles for the stiffness of the beam to fall to 50% of the original stiffness value. This value was rather arbitrary and did not always correlate well to the development of macro-cracks in the test specimen. Read the entire page →
From page 99... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-3 to Prevent Fatigue Cracking in Flexible Pavements," Prowell et al. Read the entire page →
From page 100... ... B-4 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures Figure B-2. Fatigue life of NCHRP 09-10 mixes with 9 modified asphalt binders (Bahia et al., 2001) Read the entire page →
From page 101... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-5 Figure B-3 shows the correlations between asphalt binder G* Read the entire page →
From page 102... ... B-6 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures correlation was at 10°C. At all temperatures, the BBF did a reasonable job of quantifying the increase in fatigue life from increased pavement thickness. Read the entire page →
From page 103... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-7 the number of cycles and the number of cycles to failure defined as the cycle where the ratio was equal to 0.5. Figure B-6 shows a summary of the asphalt binder fatigue parameter results from this study compared to the laboratory fatigue results. Read the entire page →
From page 104... ... B-8 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures Figure B-6. Comparison of PCAS asphalt binder G* Read the entire page →
From page 105... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-9 study. Phase II of the study compared the magnitude of the endurance limit from the laboratory to the measured field strain distributions in the test track sections. Read the entire page →
From page 106... ... B-10 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures Figures B-9 and B-10 show the results of the comparison between laboratory mixture fatigue and the asphalt binder fatigue tests used in this study. e results of this study showed that there were strong correlations between mixture fatigue life and both binder tests evaluated. Read the entire page →
From page 107... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-11 1990; Christensen and Bonaquist, 2012; Underwood et al., 2012) Read the entire page →
From page 108... ... B-12 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures The Texas OT was developed in the late 1970s at the Texas Transportation Institute (TTI) by Germann and Lytton as a means of simulating the movement of joints or cracks in a pavement, as discussed earlier (Germann and Lytton, 1979) Read the entire page →
From page 109... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-13 work with (Zhou and Scullion, 2003, 2005) Read the entire page →
From page 110... ... B-14 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures in test load as cracks develop and move through the test specimen. Phase II is the late propagation phase and is indicated by the slow decrease in the maximum load applied to the specimen, with the load staying in phase with the displacement. Read the entire page →
From page 111... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-15 A study of the sensitivity of the OT showed that it was sensitive to mixture properties, including temperature, asphalt content, asphalt type, aggregate type, and air voids. The OT results were also found to be sensitive to the displacement used to run the test. Read the entire page →
From page 112... ... B-16 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures Figure B-18 that the softer asphalt binders, particularly those with polymer modifiers perform better in the OT than stiffer asphalt binders (Zhou and Scullion, 2003) Read the entire page →
From page 113... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-17 facility (Zhou et al., 2007) Read the entire page →
From page 114... ... B-18 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures A study by Zhou et al. Read the entire page →
From page 115... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-19 Mixes from five test sections located on the National Center for Asphalt Technology (NCAT) test track were used by Ma to recommend a new method of determining the failure point of the overlay test based on a normalized load cycle procedure. Read the entire page →
From page 116... ... B-20 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures Mixture Fatigue Test Methods Selected for Use in NCHRP 09-59 Both the BBF and OT methods have been evaluated to determine their effectiveness at predicting asphalt mixture cracking resistance. The BBF test showed reasonable correlations with field performance and was able to distinguish between different mixture properties. Read the entire page →
From page 117... ... Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 B-21 Harvey, J Read the entire page →
From page 118... ... B-22 Relationships Between the Fatigue Properties of Asphalt Binders and the Fatigue Performance of Asphalt Mixtures Zhou, F., H Read the entire page →

From page 97...

... B-1 Evaluation and Selection of Mixture Fatigue Tests for Use in NCHRP 09-59 Introduction Fatigue cracking occurs in asphalt pavements as the result of repeated bending from traffic loads. This bending results in tensile strains in the asphalt layer, which result in the formation of cracks, either at the bottom of the layer for thin pavements (classical bottom-up fatigue)