This dissertation presents the integration of a damage viscoelastic constitutive
relationship with a viscoplastic relationship in order to develop a comprehensive
anisotropic damage viscoelastic-viscoplastic model that is capable of capturing hot mix
asphalt (HMA) response and performance under a wide range of temperatures, loading
rates, and stress states. The damage viscoelasticity model developed by Schapery (1969) is
employed to present the recoverable response, and the viscoplasticity model developed at
the Texas Transportation Institute (TTI) is improved and used to model the irrecoverable
strain component. The influence of the anisotropic aggregate distribution is accounted for
in both the viscoelastic and viscoplastic responses.
A comprehensive material identification experimental program is developed in
this study. The experimental program is designed such that the quantification and
decomposition of the response into viscoelastic and viscoplastic components can be
achieved. The developed experimental program and theoretical framework are used to
analyze repeated creep tests conducted on three mixes that include aggregates with
different characteristics. An experiment was conducted to capture and characterize the three-dimensional
distribution of aggregate orientation and air voids in HMA specimens. X-ray computed
tomography (CT) and image analysis techniques were used to analyze the microstructure in
specimens before and after being subjected to triaxial repeated creep and recovery tests as
well as monotonic constant strain rate tests. The results indicate that the different loading
conditions and stress states induce different microstructure distributions at the same
macroscopic strain level. Also, stress-induced anisotropy is shown to develop in HMA
specimens.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/4761 |
| Date | 25 April 2007 |
| Creators | Abdel-Rahman Saadeh, Shadi |
| Contributors | Masad, Eyad |
| Publisher | Texas A&M University |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation, text |
| Format | 2163890 bytes, electronic, application/pdf, born digital |
Page generated in 0.002 seconds