Methods to Determine Ductility of Structural Members: A Review

Abstract

Ductility plays a crucial role in ensuring the safety of a structure, as its inadequacy can lead to sudden and brittle failure. Despite its significance, there is no explicit method for determining, leading to inconsistency and confusion in selecting appropriate techniques. Misjudging a structure’s ductile behaviour can have catastrophic consequences. Therefore, this study examined several preliminary studies and identified twenty-one methods for computing ductility indices. These indices were categorized into three types, namely conventional, displacement-based, and energy-based. The conventional ductility indices are commonly applied to steel-reinforced members, deformation-based ductility indices to FRP-reinforced members, and energy-based ductility indices to earthquake-resistant and static-load structures. Conventional ductility indices are specific to ductile reinforcements, while displacement-based and energy-based ductility indices apply to both ductile and non-ductile reinforcements. However, different calculation methods can lead to significant variations in the computed ductility, particularly for those involving the first crack, and load factor, thereby leading to different ductility requirements for ensuring structural safety. Additionally, not all methods are explicit, and it is crucial to avoid indiscriminately applying requirements from one method to another.

Comparative Study on Using Steel and Glass Fiber Reinforced Polymer Rebars as Reinforcement on Flexural Behavior of Concrete Beams.

“…Three categories were established for these indices: conventional, displacement-based, and energy-based. Conventional ductility indices are exclusive to ductile reinforcements, but indices based on displacement and energy can be applied to both non-ductile and ductile reinforcements [34]. A recommended model was put out to calculate the ductility (μ) of fiber-reinforced polymer beams [35].…”

Behavior of Fatigue Damaged Reinforced Concrete One-Way Slabs Repaired With CFRP Sheets

“…This point should be limited below the deformation capacity since it is the site with the most significant displacement and the region with the maximum potential energy. The total area below the load-deflection curve at ultimate failure is computed to indicate energy absorption [32][33][34]. The deformability index DI [35] defines deformability as the ratio of the material's deflection to the final deflection at a fracture.…”

Design of Reinforced Concrete Structure With Ordinary Moment Frame in Low Seismic Region (Case Study: Midrise Shopping Building in Singkawang City)

“…A structure's safety relies heavily on ductility, which can result in sudden and brittle failures. (Ling et al, 2023). Ductile behavior can provide substantial assurance and guarantee sufficient deformation capacity before failure occurs.…”