Low-frequency uniaxial stress reversal fatigue behavior of plain concrete
| dc.contributor.author | Nasir, Raza | |
| dc.contributor.examiningcommittee | Fiorillo, Graziano (Civil Engineering) | |
| dc.contributor.examiningcommittee | Bassuoni, Mohamed T. (Civil Engineering) | |
| dc.contributor.supervisor | Svecova, Dagmar | |
| dc.date.accessioned | 2024-09-19T14:37:57Z | |
| dc.date.available | 2024-09-19T14:37:57Z | |
| dc.date.issued | 2024-09-17 | |
| dc.date.submitted | 2024-09-17T21:53:30Z | en_US |
| dc.degree.discipline | Civil Engineering | |
| dc.degree.level | Master of Science (M.Sc.) | |
| dc.description.abstract | This thesis investigates the uniaxial stress reversal fatigue behavior of plain concrete under low-frequency cyclic loading, with a focus on frequencies below 1 Hz. The research aims to enhance the understanding of the fatigue life of concrete structures, particularly in infrastructure subjected to repeated loading such as dams and bridges. The specimens were tested at three specific frequencies: 0.2 Hz, 0.5 Hz, and 0.75 Hz. These tests were performed under a constant stress range of 11.4 MPa, replicating the stress conditions identified through Finite Element Analysis of a spillway from an existing gravity dam in northern Manitoba. The testing regime set the maximum stress level at 90% of the tensile strength of the concrete and the minimum stress level at 20% of the compressive strength of the concrete. The analysis concentrated on evaluating the fatigue life of concrete, examining maximum strain curves, stiffness degradation, and energy dissipation under stress reversal conditions. The analysis revealed that higher frequencies generally resulted in a longer fatigue life. The maximum strain and stiffness degradation curves exhibited typical S-shaped patterns, indicating progressive damage accumulation in the concrete specimens, and increasing strain at failure. Additionally, stiffness degradation showed negligible differences in deterioration indices between 0.5 Hz and 0.75 Hz, with slightly higher deterioration observed at 0.2 Hz. Energy analysis indicated that higher frequencies result in increased energy dissipation per fatigue cycle. The application of the Weibull distribution effectively modeled the variability in fatigue life data, providing insights into the probabilistic nature of concrete's fatigue behavior under stress reversal loading. Furthermore, the research included a validation of the stress reversal fatigue model proposed by Ferreira et al. (2024). The model's applicability across different frequencies was assessed, demonstrating its potential for broader application in predicting the fatigue behavior of concrete under uniaxial stress reversal loading. | |
| dc.description.note | February 2025 | |
| dc.identifier.uri | http://hdl.handle.net/1993/38625 | |
| dc.language.iso | eng | |
| dc.rights | open access | en_US |
| dc.subject | uniaxial stress reversal fatigue | |
| dc.subject | concrete | |
| dc.subject | maximum strain curves | |
| dc.subject | stiffness degradation | |
| dc.subject | energy dissipation | |
| dc.subject | Weibull distribution | |
| dc.title | Low-frequency uniaxial stress reversal fatigue behavior of plain concrete | |
| dc.type | master thesis | en_US |
| local.subject.manitoba | yes | |
| oaire.awardTitle | Graduiat | |
| project.funder.identifier | http://dx.doi.org/10.13039/100014611 | |
| project.funder.name | Manitoba Hydro |