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This paper summarizes the guidelines provided to the numerical simulation/prediction teams that participated in the LEAP-2017 prediction exercise. These guidelines are developed for the Phase 1 of the simulations that focused on the use of cyclic triaxial element tests for calibration of constitutive models that the participating teams used in their numerical simulations/predictions.
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LEAP-2017 GWU Laboratory Tests
This project documents an extensive series of laboratory tests performed at the George Washington University to characterize the basic properties and stress-strain-strength response of Ottawa F-65 sand in cyclic loading conditions. The results of these experiments as well the monotonic and cyclic triaxial tests conducted in LEAP-2015 project were provided to all the numerical simulation teams who participated in the LEAP-2017 prediction exercise. The simulation teams used these results to calibrate the constitutive models that they planned to use in numerical simulations of LEAP-2017 centrifuge tests.
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- Award ID(s):
- 1635524
- PAR ID:
- 10474529
- Publisher / Repository:
- Designsafe-CI
- Date Published:
- Subject(s) / Keyword(s):
- Cyclic Triaxial Test Hydrulic Conductivity Liquefaction Strength Minimum And Maximum Void Ratios Ottawa F-65 Sand Stress-Strain Response
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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This paper presents a summary of the element test simulations (calibration simulations) submitted by 11 numerical simulation (prediction) teams that participated in the LEAP-2017 prediction exercise. A significant number of monotonic and cyclic triaxial (Vasko, An investigation into the behavior of Ottawa sand through monotonic and cyclic shear tests. Masters Thesis, The George Washington University, 2015; Vasko et al., LEAP-GWU-2015 Laboratory Tests. DesignSafe-CI, Dataset, 2018; El Ghoraiby et al., LEAP 2017: Soil characterization and element tests for Ottawa F65 sand. The George Washington University, Washington, DC, 2017; El Ghoraiby et al., LEAP-2017 GWU Laboratory Tests. DesignSafe-CI, Dataset, 2018; El Ghoraiby et al., Physical and mechanical properties of Ottawa F65 Sand. In B. Kutter et al. (Eds.), Model tests and numerical simulations of liquefaction and lateral spreading: LEAP-UCD-2017. New York: Springer, 2019) and direct simple shear tests (Bastidas, Ottawa F-65 Sand Characterization. PhD Dissertation, University of California, Davis, 2016) are available for Ottawa F-65 sand. The focus of this element test simulation exercise is to assess the performance of the constitutive models used by participating team in simulating the results of undrained stress-controlled cyclic triaxial tests on Ottawa F-65 sand for three different void ratios (El Ghoraiby et al., LEAP 2017: Soil characterization and element tests for Ottawa F65 sand. The George Washington University, Washington, DC, 2017; El Ghoraiby et al., LEAP-2017 GWU Laboratory Tests. DesignSafe-CI, Dataset, 2018; El Ghoraiby et al., Physical and mechanical properties of Ottawa F65 Sand. In B. Kutter et al. (Eds.), Model tests and numerical simulations of liquefaction and lateral spreading: LEAP-UCD-2017. New York: Springer, 2019). The simulated stress paths, stress-strain responses, and liquefaction strength curves show that majority of the models used in this exercise are able to provide a reasonably good match to liquefaction strength curves for the highest void ratio (0.585) but the differences between the simulations and experiments become larger for the lower void ratios (0.542 and 0.515).more » « less
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