3. Producción
Browse
2 results
Search Results
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Specific dissipated energy as a failure predictor for uniform sands under constant volume cyclic simple shear loading(Springer Science+Business Media, 2021-10-27)An experimental study was performed to investigate the dissipated energy to failure of sand samples subjected to uniform and non-uniform cyclic simple shear loading. The hypothesis evaluated was that for a given initial sample state the specific dissipated energy required to reach failure should be reasonably constant independent of the type of stress-time history used in the testing. Test samples consisted of dry Ottawa sand prepared at nine different initial states that were subjected to different stress controlled cyclic horizontal shear loading waveforms that included 15 uniform sinusoidal waves and up to 33 non-uniform loading wave forms. The experimental program presented showed that the measured cumulative dissipated specific energy to failure, defined when the double amplitude shear strain reaches 7.5%, for the different sample initial states was reasonably constant but with coefficients of variation ranging between 13 to 44%. As expected, the cumulative dissipated energy increased with increasing initial stress level and relative density. The findings support the notion that specific dissipated energy can be used as a reasonable failure predictor for uniform dry sands based on their initial state and are independent of the type of cyclic simple shear loading waveform using in the testing. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Evaluating the Resilience of Urban Road Networks Against Recurrent Disruptions: A Hysteretic Approach(Institute of Electrical and Electronics Engineers Inc., 2026-01-01)Performance-based resilience measures arise from the need to quantify the dynamic response of transportation systems to extreme disruptive events, where recovery is central. Extending the scope of these measures to recurrent events demands a proper assessment of the disruptive stage, which exhibits a progressive behavior determined by cascading failure. To account for both disruptive and recovery stages, we propose a hysteretic model built upon standard traffic microsimulation data, where the arriving flow is described by a three-stage Ornstein-Uhlenbeck stochastic process. By relating its deterministic component to the solution of a differential equation analogous to a mass-spring system, we construct a hysteresis curve that describes system resilience as a unified process, covering both the disruptive and recovery stages, whereas its enclosed area represents performance loss. Finally, we propose a new quantitative resilience measure, the normalized hysteretic resilience (NHR), associated with the hysteresis loop. The methodology is demonstrated for the case study of the influence area of a bus rapid transit (BRT) terminal when a critical segment is blocked by a traffic accident. Findings show that the NHR measure is suitable to quantify the nonlinear behavior of traffic flows and consistent with existing resilience measures.