| dc.description.abstract | The main goal of this dissertation is to develop simple and accurate models for the
transient monotonic and cyclic deformation behaviour of bitumen and asphalt mixes.
The first part of this dissertation is concerned with an experimental and theoretical
investigation of the deformation behaviour of bitumen. The second part is concerned
with the deformation of bituminous mixes.
A brief description of the main literature on composition, structure and mechanical
behaviour of pure and polymer-modified bitumens is presented in chapter 2.
An extensive experimental study comprising of monotonic, continuous cyclic and
pulse loading tensile experiments for two pure and two polymer-modified bitumens
is detailed in chapter 3. Based on these experimental findings a simple constitutive
phenomenological model including the effects of rate dependent recovery is proposed
for bitumen. Comparisons between experiments and model predictions are presented
with good agreement.
The spherical indentation behaviour of bitumen under monotonic and cyclic loading
conditions is studied in chapter 4. A simple extension to the power-law indentation
model of Bower et al. (1993) is proposed for bitumen with good agreement with
experimental results.
Chapter 5 presents a review of the main research on continuum and micro-mechanical
models for the deformation behaviour of bituminous mixes.
An extensive experimental investigation of the monotonic and cyclic compressive
deformation behaviour of bituminous mixes with varying volume fractions of aggregate,
for uniaxial and triaxial conditions, is described in chapters 6 and 7, respectively.
An extension to the phenomenological model proposed for bitumen is proposed for
these mixes. The predictions of the model are compared with the experimental results
with good agreement.
In chapter 8, a micro-mechanical constitutive model for the deformation behaviour
of asphalt is assembled using micro-mechanical theories and experimental observations.
The model predictions are compared with uniaxial and triaxial experimental
results, showing reasonably good agreement.
Finally, conclusions and recommendations for future work are presented in chapter 9. | |
