الفهرس 
This chapter provides an overview of the thesis, as well as the research scope.Only 14 pages are availabe for public view
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Abstract
Reinforced Concrete (RC) columns are responsible for transferring all the loads safely from beams and slabs to the foundation. The failure in columns is mostly brittle and may lead to the collapse of the structure. The reinforcement of RC columns is divided into longitudinal reinforcement and transverse ties. In recent years, researchers have focused on increasing the ductility and strength of RC columns by using new materials and new techniques in the reinforcement, such as using fiber reinforced polymers (FRP) and various types of steel meshes, Welded Wire Mesh (WWM) and Expanded metal mesh (EMM) in addition to traditional reinforcement.
This research aim was to study the effectiveness of using single layer of WWM as internal reinforcement in addition to longitudinal bars and transverse ties in the behavior of RC columns to increase the load carrying capacity and ductility of RC columns in addition to overcome the brittle failure of RC columns. The behavior of RC columns internally reinforced with this new technique was investigated under concentric and eccentric compression load. This new reinforcement technique was applied in short and long columns in this research.
A total of thirty-six square RC columns specimens with cross-sections 115×115 mm were tested under concentric and eccentric compression till failure. The influence of three parameters was studied to provide a complete evaluation of using this new reinforcement technique; The slenderness ratio (λ) of columns specimens (λ=9 and 18), the eccentricity ratio (e/t = 0, 0.13 and 0.26), and the volumetric ratio of ties (ρ= 0.44% and 0.22%). The effects of this parameters were investigated on the ultimate load capacity, axial displacement, lateral displacement, vertical strain, and failure modes.
The experimental results demonstrated that all columns internally reinforced with WWM in addition to typical reinforcement, exhibited significant improvement in ultimate load, axial displacement, lateral displacement and ductility. Adding single layer of WWM as internal reinforcement in addition to typical reinforcement increased the ultimate load by 16.81% and 9.14% for short columns (λ = 9) and long columns (λ = 18), respectively. Increasing λ at the same e/t or increasing e/t at the same λ decreased the ultimate load and the axial displacement but increased the lateral displacement. Transverse ties can be reduced to half without reducing the load caring capacity of RC columns by adding a single layer of WWM. Using WWM as additional internal reinforcement changed the failure mode from sudden and brittle failure with bang noise to ductile failure with relativity lower noise.