Structural Performance Characteristics of Ultra-High Performance Concrete Shear Walls

Abstract

Shear walls are defined as a category of structural walls designed to resist lateral loads such as wind and seismic forces. Traditionally, reinforced concrete (RC) shear walls are built using conventional concrete and reinforcing steel rebars. However, recent advancements in novel materials, such as ultra-high performance concrete (UHPC) have enabled the use of these innovative materials to enhance the lateral load performance characteristics of shear walls. The research conducted in this thesis aims to assess the lateral load performance of UHPC shear walls. Initially, a literature review is conducted to examine the structural benefits of utilizing UHPC compared to conventional concrete. Based on the identified research gaps and questions, an experimental investigation was performed by constructing and testing two full-scale UHPC shear walls with different aspect ratios under cyclic loading. Various lateral load performance characteristics were investigated based on the experiments, such as the hysteretic behavior, crack pattern, maximum lateral strength and reinforcement strain. The results demonstrate the promising performance of UHPC shear walls, indicating increased strength and reduced susceptibility to damage. The strain on the reinforcement showed improved distribution and varied outcomes between the walls, highlighting the crucial impact of wall geometry and reinforcement design on structural performance. The study continued with developing and validating a series of finite element (FE) models in Abaqus for both squat and slender shear walls. These models were then utilized to perform a parametric study aimed at assessing the impact of axial loads on the experimental shear walls. Findings from the numerical study highlighted that axial loads enhance the initial stiffness effectively and result in a significant elevation of the load-displacement curves. However, this increase in performance comes with a trade-off, as there is also a markedly higher rate of damage progression in the shear walls subjected to axial loads compared to those without.