cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.17603/ds2-7czq-en54
title: COVID-19 and Hurricane Evacuations in Puerto Rico and the U.S. Virgin Islands

description: PLEASE MAKE SURE TO VIEW THE MOST RECENT VERSION BY CLICKING THE DROPDOWN BOX BELOW. 
This page is being constantly updated as additional research materials are made available.  

Puerto Rico and the U.S. Virgin Islands (PRVI) region is particularly vulnerable to the hazards of a hurricane and its associated cascading impacts from the social, infrastructure, and ecological realms. Associated landslides, non-hardened infrastructure, and immense electricity vulnerability are just some of the hazards seen in previous storms like Hurricane Maria. With the onset of the COVID-19 pandemic, even a minor hurricane has the potential to become a compound hazard when coupled with the emergency response required as social distancing is in direct conflict with human mobility and congregation. This study, conducted during 2020 and 2021, examines how the compounding hazards of the COVID-19 pandemic and hurricanes affect peoples’ risk perceptions, preparedness planning, and evacuation decisions while considering the role of social determinants of health in disasters. Two surveys were disseminated virtually, one each during the 2020 and 2021 hurricane seasons, using convenience sampling to residents in Puerto Rico and the US Virgin Islands (PRVI).  Ultimately, the COVID-19 pandemic has had a profound effect on how people make their decisions to evacuate. Over half of the sample considered themselves vulnerable to COVID-19 due to existing health concerns. When asked about their evacuation actions, a significant number of individuals who would have previously evacuated to a shelter would choose not to during the pandemic. Additionally, individuals were shown to have a negative perception of public shelter options, with many people viewing public shelters as overtly risky due to COVID-19 concerns and would instead choose to shelter-in-place despite a recommendation to evacuate to a safer location or a government-operated shelter. Data from the 2021 hurricane season, although still preliminary, have shown that vaccination status would not affect evacuation decisions for 70% of the sample. This study will help apply knowledge for future pandemic disaster planning by revealing improvements for public messaging that will ultimately save lives and determining planning and logistical requirements.
DOI: 10.17603/ds2-h0kd-5677
title: StEER - Puerto Rico Earthquake Sequence December 2019 to January 2020: Field Assessment Structural Team (FAST) Early Access Reconnaissance Report (EARR)

description: A sequence of earthquakes occurred in the southwestern region of Puerto Rico, initiating at the end of 2019. The first widely-felt earthquake occurred on December 28th, 2019 with a Mw 5.0 magnitude. This was followed on January 6th, 2020 by a much stronger event (Mw 5.8 magnitude), that was felt throughout the island and caused damage to a wide variety of structures in the southwest region of the island. The main event occurred on January 7th, 2020 at 8km S of Indios at 4:24am local time (8:24 UTC) with a magnitude Mw 6.4, followed by thousands of aftershocks. The three largest aftershocks happened on January 7th, 2020 at 8km S of Tallaboa (Mw 5.6 magnitude), on January 7th, 2020 at 9km S of Tallaboa (Mw 5.6 magnitude), and on January 11th, 2020 at 13km S of Guánica at 8:54am local time (12:54 UTC) with Mw 5.9 magnitude.The ground shaking from the earthquakes damaged over 10,000 structures, including the complete collapse of at least 80 structures, most of which were single-family
residential units. In addition, several bridges, roads and other infrastructure were also damaged or destroyed and two thirds of the island lost power as a result of the Mw 6.4 earthquake on January 7th. This Early Access Reconnaissance Report (EARR) is StEER’s second product for this event. It provides an overview of the sequence of earthquakes and preliminary findings
based on the data and observations generated by the Field Assessment Structural Team (FAST). The FAST documented the performance of 60 structures located in six different cities along the southwestern coast of Puerto Rico between the cities of Ponce and Mayagüez.
DOI: 10.17603/ds2-jfjy-0122
title: Inorganic carbon and carbon isotope analysis
title: in Characterization and Geotechnical Properties of Wildfire Ashes

description: This project summarizes the geotechnical engineering properties of eight samples of wildfire ash sampled from three different wildfire sites in central and southern California. This data can be used in conjunction with data collected from others to provide a database of the physical, chemical, hydrological, and engineering properties of wildfire ashes. Extensive engineering testing of wildfire ashes is not readily available in literature, so this work will supplement the supply currently available. This work would be information and educational for those researching wildfire ashes, fire-exposed slopes, carbonate-rich soils, and manmade soils, including other types of ash. This data can be reused by those who would like reference data for further testing on wildfire ashes and for those who require reference data on soil engineering properties.
description: Total inorganic carbon (TIC) content was measured using a total carbon analyzer. Ash powders were sieved over the No. 40 sieve and ground to fine powder. The carbonate fractions of ash powders were dissolved in weak (10% v/v) phosphoric acid at room temperature overnight within individual, evacuated Exetainer® vials. An Automate® Carbonate Preparation device passed evolved CO2 into a G2121-i Picarro® carbon isotope analyzer and carbonate contents and 13C/12C ratios determined via Cavity Ringdown Spectroscopy (CRDS). Carbon contents reported as total inorganic carbon (wt% TIC) and projected calcium carbonate abundances (wt% CaCO3) (Equations 3 and 4). Carbon isotope values were determined by comparison with international (NIST SRM 915B, IAEA NBS-18, Carrera Marble) and laboratory (CRCP90, CRC200) standards and reported in the typical -notation (13C) (Equation 5) versus the VPDB standard in ‰. TIC, projected calcium carbonate and 13C reproducibility are better than +/– 0.6 wt%, +/– 4.4 wt% and +/– 0.3‰, respectively. The isotope composition provided information about the origin of the carbon species in ash.
DOI: 10.17603/ds2-n5b6-4051
title: Synthetic Ground-Motion Records for 100 Bridge Sites in Indiana

description: This dataset contains synthetic ground-motion time histories from scenario earthquakes generated for 100 bridge sites across the State of Indiana. As part of the Joint Transportation Research Program (JTRP) project SPR-4222 supported by the Indiana Department of Transportation (INDOT), these synthetic ground motions were used as the seismic input for the vulnerability assessment of Indiana’s bridge network. All ground motions were generated for a return period of ~1000 years (7% probability of exceedance in 75 years) using stochastic and deterministic simulation techniques. These synthetic records constitute a valuable tool for future research projects related to seismic risk assessment of civil infrastructure in the Central and Eastern United States (CEUS).
DOI: 10.17603/ds2-qrt3-8730
title: Cyber-physical Optimization of Parapet Wall Height for a Low-rise Building Model
title: in Cyber-Physical Systems Approach for the Optimal Design in Wind Engineering: Parapet Walls

description: This experiment contains pressure measurements collected from boundary layer wind tunnel tests of a 1:18 low-rise building model. The building model has a parapet wall whose height was adjusted according to an overarching optimization algorithm. Independent optimization runs were conducted implementing one of three optimization algorithms.

First, a single-objective particle swarm optimization (SO-PSO) algorithm was implemented to independently test two optimization problems: one to minimize roof and parapet suction pressures, and one to minimize roof and parapet suction pressures incorporating a forgetting function. Second, a non-stochastic golden section search (GSS) algorithm was implemented to independently test two optimization problems to minimize the maximum magnitude of peak pressures on the roof and parapet surfaces: one considering suction only, and one considering both suction and positive pressure. Third, a multi-objective particle swarm optimization (MO-PSO) algorithm was implemented to minimize peak suction pressures on the roof and minimize peak building base shear. For all three optimization algorithms implemented, the model was evaluated at 45 and 90 degrees. The model was instrumented with 512 pressure taps. Pressure measurements were collected using a high-speed pressure scanner from Scanivalve. The data files are in .mat format.
description: The research objective of this project is to develop a cyber-physical systems (CPS) approach to the optimal design of structures for wind hazards. The approach combines the accuracy of physical wind tunnel testing with the efficiency of numerical optimization algorithms to create an efficient approach to structural design. Experiments are executed in a wind tunnel, sensor feedback is monitored by a computer, and optimization algorithms dictate physical changes to the model in the wind tunnel. The traditional design process involving wind tunnel testing is an iterative procedure that can take weeks or months. Rather than having to construct multiple entirely new models, a model with physically adjustable parameters can be used to streamline the design process to efficiently reach the optimal solution much quicker than purely experimental methods and with a higher degree of realism than purely numerical methods. These experiments represent a portion of the project and they involve the testing results of a mechatronic low-rise building model with an outer parapet wall of variable height.
DOI: 10.17603/ds2-re6v-3a84
title: A Database of 1D Nonlinear Ground Response Simulations in the Sacramento-San Joaquin Delta region of California
title: in Nonlinear site response of soft soil sites in the Sacramento-San Joaquin Delta region of California

description: A Database of 1D Nonlinear Ground Response Simulations in the Sacramento-San Joaquin Delta region of California
description: This project presents 1D nonlinear ground response simulation results for 50 sites in California's Sacramento-San Joaquin Delta region. The simulations are based on 569 input motions selected from the NGA-West2 database, with PGA values ranging from 0.008 g to 1.0 g. Each site was modeled using one base profile and 100 randomized profiles, with randomization applied to key soil nonlinear parameters, including pseudo-reference strain, minimum damping, and shear strength. The analyses were performed on Frontera using DEEPSOIL Linux solver and the results are stored in a relational database format (.db3) for each site.
DOI: 10.17603/ds20d79
title: Wall Panel Test 2
title: in NEESR: Seismic Performance of Conventional and Innovative Special Structural Walls

description: Reversed-cyclic pseudo static test of reinforced concrete wall panel representing plastic hinge region of a wall
description: The project explored design and performance limits for structural walls, considering both conventional wall construction practices and innovative construction practices. A principal finding of recent earthquakes (in 2010 and 2011) and laboratory tests from 200 to 2010 is that wall performance is limited by stability and ductility capacity of the flexural compression zone. Given this critical issue, a series of studies on conventional walls and boundary elements constructed with innovative materials (HPFRCC) to establish performance limits for flexural compression failures in reinforced concrete structural walls. Tests were designed to acquire knowledge, improve construction practices, and advance simulation tools. The primary research outcomes include: 

(1)	Completing  tests of eight ordinary boundary element (OBE) prisms at UCLA. The test specimens were detailed according to ACI 318-11 21.9.6.5 with the goal of assessing failure modes and strain capacities as influenced by concrete cover, configuration of transverse reinforcement, and spacing of transverse reinforcement. Based on the tests, a relationship used to assess buckling of longitudinal reinforcement was extended to wall boundaries with typical OBE detailing. 
(2)	Completing tests on 13 special boundary element (SBE) prisms at UC Berkeley. The tests investigated the role of boundary element detailing and wall thickness. The tests indicated that the strain capacity of relatively (< 12 inches) walls with ACI 318 code compliant SBE detailing was less than one percent and that improved detailing or high-performance, fiber-reinforced concrete did not improve the strain capacity significantly. 
(3)	Conducted tests on seven, approximately one-half scale wall panels represented the base of roughly 8 to 10 story walls in a moderately tall building.  The primary test variables were the configuration and quantity of boundary transverse reinforcement, the depth of the neutral axis, and the wall thickness. The test provided essential data to develop a new, displacement-based model for predicting the drift capacity of structural walls with SBE. 
(4)	Developing code change proposals that were approved for ACI 318-14 and additional code change proposals that have been approved for inclusion in ACI 318-19. 
(5)	Creating and documenting a detailed dataset that was uploaded to DesignSafe-ci Data Depot that can be used for future reserarch.
DOI: 10.17603/ds2-d56j-h615
title: Microtremor Horizontal-to-Vertical Spectral Ratio (mHVSR) Data Collection at Brentwood, 2022
title: in Microtremor Measurements Performed Within Southern California

description: Microtremor Horizontal-to-Vertical Spectral Ratios (mHVSR) are derived from ratios of the horizontal and vertical components of a Fourier Amplitude Spectra (FAS) from a 3-component recording of microtremors. This is done by recording ground vibrations either from a temporarily-deployed broadband seismometer, typically recording for a relatively short period of time (~1-2 hrs.), or from a permanently-installed broadband seismometer for a longer period of time. mHVSR can be very useful in identifying resonant frequencies where peaks in mHVSR represent resonance from impedance contrasts at a site. Many studies have found that the lowest resonant peak found in mHVSR is associated with the fundamental frequency of site. This study aims to perform mHVSR surveys at various sites in southern California to aid in the development of site response models by utilizing mHVSR to inform them and to also aid in the development of a large publicly accessible database for use in furthering research using mHVSR. This work will aid in a larger project associated with another DesignSafe doi (PRJ-4064). The database has been established and is available in the United States Community Shear-Wave Velocity (VS) Profile Database (PDB) (https://vspdb.org); the work presented in this doi is contributing to this database.
description: The Brentwood Veteran Affairs (VA) Complex is situated near the Santa Monica mountains within the West Los Angeles area. This area experiences seismic activity due to its proximity to the Santa Monica fault and other faults within the LAB. In an effort to better understand the geology and also aid in future site response model development, microtremor Horizontal-to-Vertical Spectral Ratio (mHVSR) surveys were performed specifically near vertical arrays. Collaborative research between the University of Southern California (USC) and the University of California, Los Angeles (UCLA) have performed mHVSR surveys at 10 areas within the Heroes golf course area of the VA complex. The HVSR spectra developed using this dataset may be accessed in the United States Community Shear-Wave Velocity (VS) Profile Database (PDB) (https://vspdb.org). This work was supported by the Sonny Astani Department of Civil and Environmental Engineering at the Viterbi School of Engineering, University of Southern California(USC).
DOI: 10.17603/ds2-dzwp-3964
title: Research Experiences for Undergraduates (REU), NSF NHERI 2024: Dynamic Characterization of Portland Soil Using Resonant Column Torsional Shear Testing

description: This research project focuses on the dynamic properties of soil from Portland Airport under various stress conditions using a Stokoe-type Resonant Column Testing System (RCTS). The primary objective of the study is to analyze the shear wave velocity (Vs) and stiffness of sand samples under different pressures, both normally consolidated (NC) and overconsolidated (OC), to understand their behavior in response to varying stress conditions. The project involves detailed experimentation, data collection, and analysis to observe changes in sand properties, especially when subjected to increasing and then decreasing pressures.

The data generated from this project can be reused in multiple ways. For example, it can be employed in further studies comparing the behavior of different soil types under similar conditions or in simulations to predict the response of soils in various geotechnical engineering applications. Moreover, the data can be utilized to refine existing models of soil behavior, contribute to developing new predictive tools for earthquake engineering, or aid in designing foundations and other structures in regions prone to seismic activity.

This project is unique due to its comprehensive approach to understanding the dynamic properties of sand under both normal and overconsolidated states. The use of a Stokoe-type RCTS provides high-resolution data, making it possible to capture subtle variations in the material's behavior. Additionally, the project stands out because of its focus on both increasing and decreasing pressure conditions, which is not commonly addressed in typical soil mechanics studies. This dual approach offers a more holistic view of soil behavior, particularly under cyclic loading conditions, which is critical for understanding and predicting soil performance in real-world scenarios.

The primary audience for this research includes geotechnical engineers, researchers in soil mechanics, civil engineers involved in foundation design, and earthquake engineering professionals. Additionally, the findings from this project would be valuable to academic institutions, students studying geotechnical engineering, and professionals involved in infrastructure development in seismically active regions.
DOI: 10.17603/ds2-t4kz-0c30
title: Test MKH05 - Centrifuge Modeling of Cone Penetration Testing in Layered Soil
title: in Liquefaction Evaluations of Finely Interlayered Sands, Silts and Clays

description: A centrifuge model test was used to examine the effect of soil interlayering on the measured cone penetration resistance in a layered soil model. The centrifuge model included a layer of loose or dense sand with varying thickness between overlying and underlying layers of low plasticity clayey silt. The sand was loose with a relative density of 44% on one side of the model, and dense with a relative density of 88% on the other side. The clayey silt had a plasticity index (PI) of 6 and over-consolidation ratio (OCR) of about 1.5. Multiple cone penetration soundings were performed using cone penetrometers with diameters of 4, 6 and 10 mm. The results showed the measured tip resistance in layered soil as well as the sensing and development distances depend on cone diameter, sand layer thickness, and stiffness contrast between the subsequent soil layers. The results provide insights on the effect of thin layer presence on cone tip measurements and an archived dataset for evaluating design procedures and numerical analysis methods. The data has been subject to quality control before publishing. The process by which it was assessed and the issues found are described in the Data Report.
description: The effect of soil interlayering on the measured cone penetration resistance was examined in a layered soil model tested on a 9-m radius centrifuge. The soil profile consisted of a layer of sand between overlying and underlying layers of low plasticity clayey silt. The sand layer thickness varied from 0 to 240 mm (model scale) along the length of the model. The sand was loose with a relative density of 44% on one side of the model, and dense with a relative density of 88% on the other side. The clayey silt had a plasticity index (PI) of 6 and over-consolidation ratio (OCR) of about 1.5. Multiple cone penetration soundings were performed along the width and length of the model using cone penetrometers with diameters of 4, 6 and 10 mm.
DOI: 10.17603/ds2-zvfc-a420
title: Natural Hazards Research Summit 2024: O.H. Hinsdale Wave Research Laboratory

description: The Hinsdale Wave Research Laboratory (HWRL is a state-of-the-art experimental facility conducting fundamental and applied research in coastal and ocean engineering and science via physical model experiments. Through our work we deliver research, testing, education, and outreach to improve the resilience and sustainability of coastal areas, and to develop innovative solutions to the design of coastal infrastructure.

The HWRL offers a two unique facilities:  the Large Wave Flume, the largest facility of it’s kind of any US academic institution and the Directional Wave Basin for considering fully 3-dimensional phenomena.  Our facility offers a complete suite of instrumentation to measure free-surface, 3D velocities, pressure, turbidity, multi-axial loads, position, stress, 6DOF motions, and bottom profilers for mobile bed experiments. Our data acquisition modules incorporates synchronized measurements with a dedicated system with more than 192 channels and sampling rates exceeding 10 kHz depending on the number of channels and the specific application. Accurate surveying techniques include LiDAR, Total Station and Laser Range Finders.
DOI: 10.17603/ds2-80d8-9m83
title: U.S. National Vs30 Maps Informed by Remote Sensing and Machine Learning

description: The shear-wave velocity time-averaged over the upper 30 m (VS30) is widely used as a proxy for site effects, forms the basis of seismic site class, and underpins site-amplification factors in empirical ground-motion models. Many earthquake simulations therefore require VS30. This presents a challenge at regional scale, given the infeasibility of subsurface testing over vast areas. While various models for predicting VS30 have thus been proposed, the most popular U.S. national, or “background,” model is a regression equation based on just one variable. Given the growth of community datasets, satellite remote sensing, and algorithmic learning, more advanced and accurate solutions may be possible. Towards that end, we develop national VS30 models and maps using field data from over 7,000 sites and machine learning (ML), wherein up to 17 geospatial parameters are used to predict subsurface conditions (i.e., VS30). Of the two models developed, that using geologic data performs marginally better, yet such data is not always available. Both models significantly outperform existing solutions in unbiased testing and are used to create new VS30 maps at ~220 m resolution. These maps are updated in the vicinity of field measurements using regression kriging and cover the 50 U.S. states and Puerto Rico. Ultimately, and like any model, performance cannot be known where data is sparse. In this regard, alternative maps that use other models are proposed for steep slopes. More broadly, this study demonstrates the utility of ML for inferring below-ground conditions from geospatial data, a technique that could be applied to other data and objectives.