Confined rubberised concrete (CRC) was found to be capable of sustaining much larger deformations compared to conventional concrete. Therefore, CRC is believed to have the potential to be used in deformable structural components. This thesis aims to investigate and model the mechanical behaviour of CRC.
The investigation initially examines conventional concrete and develops the methodology to address this issure. The true tri-axial apparatus Mac2T is used to simulate passive confinement physically and investigates the concrete loading paths. The results show that the loading path of FRP-confined conventional concrete overlaps with its failure surface. With passive confinement, conventional concrete initially exhibits perfectly plastic up to a lateral strain of 0.008. A plasticity-based material model is proposed for FRP-confined concrete, based on the experimental observations.
The failure mechanism of passively confined rubberised concrete is shown to be similar to that of conventional concrete. The loading path of passively confined rubberised concrete moves along the failure surface when subjected to compressive loads, and it soften when the lateral expansion is larger than 0.008.
With less strength and stiffness, rubberised concrete is more deformable than conventional concrete. At the same level of compressive loading, the deformation in the loading direction of FRP-confined rubberised concrete can be ten times larger than that of the conventional concrete, which could open up opportunities for creating novel structural solution. The material model, developed and implemented in the FEA package ABAQUS, can be used for numerical analysis of such solutions.
