题名: |
Investigation of Modified Aqtbah Perfomiance Using SHRP Binder
Specification |
作者: |
Hussain U. Bahia, Ph. D, Assistant Professor
Peter J. Bosacher, Ph.D., P.E., Associate Professor
JefiBr^ S. Russell, Ph.D., P.E., Associate Professor
Suwidio ThooMS |
关键词: |
Pavement Temperature, Weather Data, Modified Asphalts, Superpave, Reflective Cracking |
摘要: |
The Pavement Research Division of the Wisconsin Department of Transportation (WisDOT) initiated this project as a result of
concerns regarding excessive premature cracking of asphaltic pavements. The objectives of the project were to filed validate the
Superpave binder specification criteria and to field validate the pavement temperature estimation procedure used in the original
Superpave software.
Six test sections were constructed on USH 53 in Trempealeau County to monitor how weather conditions can affect pavement
temperature at surface and as a function of pavement depth, using pavement instrumentation and a weather station. The asphalt cement
used in d:e surface layer and the binder layer were varied for each test sections, and the type of mixture and pavement structure were
similar for the six test sections. Two modified asphalts, graded at PG 58-34 and PG 58-40, a:id one conventional asphalt graded as PG
58-28 (120-150 penetration grade), were used in the study to investigate relation between thermal cracking and performance related
properties of these asphalt binders.
This report includes analysis of the data collected during the first 22 months of the project The analysis resulted in
developing statistical models for estimation of pavement minimum and maximum temperature from meteorological data.
The models (called the Wisconsin models) were compared to the Superpave recommended model and to the more recent
model recommended by LTPP program . The analysis indicates that there is a strong agreement between the Wisconsin
model and the new LTPP model for the estimation of minimum pavement design temperature. The analysis, however,
indicates that the LTPP model and the Superpave model underestimate the maximum pavement design temperature at air
temperatures higher than 40 The analyses also indicate that there are significant differences between the standard
deviation of air temperatures and the standard deviation of the pavement temperatures. The Wisconsin models and the
pavement standard deviations are recommended for estimating the required PG rades to be used in Wisconsin
The report also includes the results of the surface condition surveys and its relation to the properties of the asphalts
used in the test sections. The performance analysis could not be used for evaluating the Superpave binder criteria because
all sections suffered from reflective cracking. Although there were significant differences in severity of reflective cracking,
no strong correlations could be found with asphalt binder properties. The results indicate that the modified binders used in
this study did not result in reduction of reflective cracking.
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报告类型: |
科技报告 |