Strain-ageing effects on the residual low-cycle fatigue life of low-carbon steel reinforcement

Loporcaro, Giuseppe; Cuevas, Alberto; Pampanin, Stefano; Kral, Milo V.

doi:10.1617/s11527-022-01885-0

Cited by 5 publications

(2 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The authors also performed a permeability-based damage assessment, highlighting a significant reduction in terms of axial strain and compressive strength capacity for concrete of damaged members. Recently, Loporcaro et al (2018Loporcaro et al ( , 2022 experimentally investigated the effects of strain ageing in reducing the residual fatigue life of steel reinforcement.…”

Section: Seismic Residual Capacity and Statedependent Fragility Analysismentioning

confidence: 99%

Energy-based procedures for seismic fragility analysis of mainshock-damaged buildings

Pedone

Gentile

Galasso

et al. 2023

Front. Built Environ.

Self Cite

View full text Add to dashboard Cite

In recent decades, significant research efforts have been devoted to developing fragility and vulnerability models for mainshock-damaged buildings, i.e., depending on the attained damage state after a mainshock ground motion (state-dependent fragility/vulnerability relationships). Displacement-based peak quantities, such as the maximum interstory drift ratio, are widely adopted in fragility analysis to define both engineering demands and structural capacities at the global and/or local levels. However, when considering ground-motion sequences, the use of peak quantities may lead to statistical inconsistencies (e.g., fragility curves’ crossings) due to inadequate consideration of damage accumulation. In this context, energy-based engineering demand parameters (EDPs), explicitly accounting for cumulative damage, can help address this issue. This paper provides an overview of recent findings on the development of aftershock-fragility models of mainshock-damaged buildings. Particular focus is given to state-of-the-art frameworks for fragility analyses based on cumulative damage parameters. Moreover, a literature review on damage indices and energy-based concepts and approaches in earthquake engineering is reported to better understand the main advantages of the mostly adopted energy-based parameters, as well as their limitations. Different refinement levels of seismic response analyses to derive fragility relationships of mainshock-damaged buildings are also discussed. Finally, the benefits of adopting energy-based EDPs rather than, or in addition to, peak quantities in state-dependent fragility analyses are demonstrated on a reinforced concrete frame building. Specifically, a refined lumped plasticity modeling approach is adopted, and sequential cloud-based time-history analyses of a Multi-Degree-of-Freedom (MDoF) model are carried out. The results highlight that energy-based approaches for fragility analysis effectively capture damage accumulation during earthquake sequences without inconsistencies in the obtained statistical models. On the other hand, estimating global or local structural capacity in terms of cumulative EDPs is still challenging. Further experimental data are needed to better calibrate the quantification of energy-based damaged states.

show abstract

Section: Seismic Residual Capacity and Statedependent Fragility Analysismentioning

confidence: 99%

Energy-based procedures for seismic fragility analysis of mainshock-damaged buildings

Pedone

Gentile

Galasso

et al. 2023

Front. Built Environ.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The same authors ( [18]) experimentally investigated the residual capacity and the effects of repair intervention on three beam-column joints subassemblies extracted from a 22-storey RC building demolished after the 2010-2011 Canterbury earthquake sequence. Moreover, the effects of strain ageing on the residual fatigue life of steel reinforcement have been also investigated (e.g., [19]).…”

Section: Residual Capacity Rc Structures: Literature Reviewmentioning

confidence: 99%

Simplified Analytical/Mechanical Procedure for the Residual Capacity Assessment of Earthquake-Damaged Reinforced Concrete Frames

Matteoni,

Pedone,

D'Amore

et al. 2023

Proceedings of the 8th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COM

View full text Add to dashboard Cite

The series of recent catastrophic earthquakes worldwide have further emphasized the evident complexity and difficulty related to the evaluation of the post-earthquake seismic residual capacity of buildings. In the aftermath of a major seismic event, a fast, yet effective, safety evaluation procedure for earthquake-damaged buildings is critical to speed up and support the definition of emergency planning strategies, as well as to provide useful intel to the stakeholders and aid the decision-making process to enhance community resilience. Therefore, this paper aims to investigate the possible implementations of a procedure based on SLaMA (Simple Lateral Mechanism Analysis) methodology for the seismic assessment of damaged Reinforced Concrete (RC) frame buildings. The proposed procedure is based on the use of reduction coefficients for damaged structural members, in line with the FEMA 306 approach, and an update of the "hierarchy of strength" at the subassembly level by accounting for the earthquake-related damage. Results are compared against a numerical model in terms of a Capacity vs. Demand Safety Index" (IS-V or %New Building Standard, %NBS) and Expected Annual Losses (EAL). Moreover, the simplified procedure can be used to assess the feasibility and effects of a repair/retrofit solution. Results show that the proposed analytical procedure is able to estimate with reasonable accuracy, considering its simplified nature, and the performance of the building when compared to numerical analyses. Finally, the effect of the use of low-damage exoskeletons based on the PRESSS low-damage technology has been evaluated via the application of the Displacement-Based Retrofit procedure.

show abstract

Comparison of Warm and Cold Forging with Friction Welding for Inner Constant Velocity Joints (CVJs)

Afseoren,

Ersoz,

Yildirim

2024

Trans Indian Inst Met

View full text Add to dashboard Cite

Driveshafts are used in all vehicles, and their service life is expected to be at least three years or 100.000 km. Many driveshaft manufacturers prefer friction welding due to its relatively cheaper cost and ease of the process. However, they should meet some property-related criteria to achieve the expected lifetime. The forging technique becomes essential to succeed in these mechanical requirements. A comparative study evaluates the performance of constant velocity joints (CVJs) produced by multi-step warm–cold forging and friction welding processes. Medium carbon steels were used in both of the techniques. The microstructures, mechanical properties (i.e. hardness, strength, impact energy and shear strength), low-cycle fatigue (LCF) properties, wear resistance and cost-efficiency (number of operations, material saving, number of produced components and cost) are compared in detail for an industrial production point of view. The experimental results reveal that warm–cold forged specimens exhibit superior mechanical properties such as increased strength, hardness, relatively higher impact energy, improved shear strength, relatively longer LCF life and enhanced wear resistance (lower wear volume loss). In addition, it is also assessed that warm–cold forging is a more cost-effective manufacturing process (reduced weight, decreased number of operations and increased yield) in the production of CVJs compared to the friction welding process.

show abstract

Strain-ageing effects on the residual low-cycle fatigue life of low-carbon steel reinforcement

Cited by 5 publications

References 22 publications

Energy-based procedures for seismic fragility analysis of mainshock-damaged buildings

Energy-based procedures for seismic fragility analysis of mainshock-damaged buildings

Simplified Analytical/Mechanical Procedure for the Residual Capacity Assessment of Earthquake-Damaged Reinforced Concrete Frames

Comparison of Warm and Cold Forging with Friction Welding for Inner Constant Velocity Joints (CVJs)

Contact Info

Product

Resources

About