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The experimental results of LEAP (Liquefaction Experiments and Analysis Projects) centrifuge test replicas of a saturated sloping deposit are used to assess the sensitivity of soil accelerations to variability in input motion and soil deposition. A difference metric is used to quantify the dissimilarities between recorded acceleration time histories. This metric is uniquely decomposed in terms of four difference component measures associated with phase, frequency shift, amplitude at 1 Hz, and amplitude of frequency components higher than 2 Hz (2 + Hz). The sensitivity of the deposit response accelerations to differences in input motion amplitude at 1 Hz and 2 + Hz and cone penetration resistance (used as a measure reflecting soil deposition and initial grain packing condition) was obtained using a Gaussian process-based kriging. These accelerations were found to be more sensitive to variations in cone penetration resistance values than to the amplitude of the input motion 1 Hz and 2 + Hz (frequency) components. The sensitivity functions associated with this resistance parameter were found to be substantially nonlinear.
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Sub-Hertz Resonance by Weak Measurement
Here we propose and demonstrate a novel weak-measurement-enhanced spectroscopy technique, which allows narrowing the resonance to 0.1 Hz and high sensitivity 7 fT/Hz^1/2 near DC in a room-temperature atomic-vapor cell, by designing a non-Hermitian Hamiltonian.
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- PAR ID:
- 10119041
- Date Published:
- Journal Name:
- Nonlinear Optics (NLO) OSA Technical Digest (Optical Society of America, 2019)
- Page Range / eLocation ID:
- NTh2A.1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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An analysis is conducted to assess the sensitivity of 17 replicas of a saturated sloping deposit tests conducted within the 2017 Liquefaction Experiments and Analysis Projects (LEAP). A difference analysis is first used to quantify the dissimilarities between recorded input acceleration time histories. This analysis provided a unique decomposition of the differences in terms of phase, frequency-shift, amplitude at 1 Hz, and amplitude of frequency components higher than 2 Hz (2+Hz). A kriging analysis was used to evaluate the sensitivity of the deposit response accelerations to differences in input motion amplitude at 1Hz and 2+Hz and cone penetration resistance. The analysis showed a response that is more sensitive to variations in cone penetration resistance values than to amplitude of the input 1Hz and 2+Hz motion (frequency) components.more » « less
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An analysis is conducted to assess the sensitivity of 17 replicas of a saturated sloping deposit tests conducted within the 2017 Liquefaction Experiments and Analysis Projects (LEAP). A difference analysis is first used to quantify the dissimilarities between recorded input acceleration time histories. This analysis provided a unique decomposition of the differences in terms of phase, frequency-shift, amplitude at 1 Hz, and amplitude of frequency components higher than 2 Hz (2+Hz). A kriging analysis was used to evaluate the sensitivity of the deposit response accelerations to differences in input motion amplitude at 1Hz and 2+Hz and cone penetration resistance. The analysis showed a response that is more sensitive to variations in cone penetration resistance values than to amplitude of the input 1Hz and 2+Hz motion (frequency) components.more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/NLO.2019.NTh2A.1
