الفهرس 
ACKNOWLEDGEMENTS
Physical and Mechanical Properties of Foam concreteOnly 14 pages are availabe for public view
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Abstract
Foam concrete is an economical structural material in cast-in place and precast construction
techniques. The microstructure of foam concrete is very complex due to the random distribution
of air voids. Previous experiments have shown a significant effect of air void content and
distribution on the compression behavior of foam concrete. While sufficient experimental
characterization has conducted on foam concrete, limited theoretical investigations have been
carried out to model the complex microstructure of foam concrete.
In this thesis, multiscale modeling was presented to extract the mechanical behavior of foam
concrete. Firstly, microscale modeling presented in numerical simulation approach is proposed to
simulate the behavior of foam concrete using representative volume element (RVE) technique. A
finite element model (FEM) was first developed and validated using available data in the literature.
Void size distribution of the RVE models variated with normal probability distribution.
The FEM model was then used to study the effect of several parameters on the behavior of foam
concrete. Simulation results show a significant effect of air void distribution and compressive
strength of mortar on the compression behavior of foam concrete. However, non-overlapped air
voids increase the compression behavior of foam concrete significantly at high void ratios of foam
concrete. In addition the increase in RVE size of foam concrete more than 3 times the void size
has no significant effect on compression behavior of foam concrete. Secondly, macro-scale of 2D
simply supported beam was modeled using multi-material topology optimization.
This method aimed to determine the variation of void ratios of foam concrete distribution within
the domain of beam to minimize the domain beam volume. The multi-material topology
optimization method can increase the performance of the design and reduce the cost of required
design using various void ratios foam concrete. Finally, it can be said that the multi scale
simulations can be used as a powerful tool for modeling the behavior of foam concrete.