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Calibrations of the PM4Silt constitutive model are presented for two low-plasticity fine-grained soils that exhibit significantly different cyclic loading be-haviors. The PM4Silt model is a stress-ratio controlled, critical state compatible, bounding surface plasticity model that was recently developed for representing low-plasticity silts and clays in geotechnical earthquake engineering applications. The low-plasticity clayey silt and silty clay examined herein were reconstituted mixtures of silica silt and kaolin with plasticity indices (PIs) of 6 and 20. Un-drained monotonic and undrained cyclic direct simple shear (DSS) tests were per-formed on normally consolidated, slurry deposited specimens. Calibration of the PM4Silt model was based on the monotonic and cyclic DSS test data, plus em-pirical relationships for strain-dependent secant shear moduli and equivalent damping ratios. The calibration process and performance of the PM4Silt constitu-tive model are described for each soil. The results illustrate that PM4Silt is capa-ble of reasonably approximating a range of monotonic and cyclic loading behav-iors important to many earthquake engineering applications and is relatively easy to calibrate.
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Simple synaptic modulations implement diverse novelty computations
Aitken et al. introduce a simple, biologically inspired model for synaptic plasticity that leads to distinct responses to novel versus familiar stimuli. Using an experimentally constrained model of a cortical circuit with plasticity at specific synapses, multiple types of complex novelty effects recently observed in experiment are simultaneously reproduced.
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- Award ID(s):
- 2223725
- PAR ID:
- 10542047
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Cell Reports
- Volume:
- 43
- Issue:
- 5
- ISSN:
- 2211-1247
- Page Range / eLocation ID:
- 114188
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.celrep.2024.114188
