RESEARCH
Interests
-
Probabilistic Risk Modeling and Analysis for Structures and Communities
-
Community Resilience & Recovery
-
Natural Hazards Risk Assessment
-
Reliability of Structures
-
Structural Engineering
-
Social Vulnerability
My current research focuses on understanding how natural hazards affect the built environment and the communities depending on it. Much of my current work centers on agricultural infrastructure and rural communities, where disruptions to critical systems can have cascading impacts on food production, economic stability, and community well-being. Through a combination of field and virtual reconnaissance, probabilistic risk assessment, structural reliability analysis, and resilience research, I investigate the performance, vulnerability, and recovery of infrastructure systems exposed to extreme events. By integrating engineering analyses with recovery and resilience perspectives, my research aims to support risk-informed decision making and improve the ability of communities to prepare for, withdstand, and recover from natural hazards.
Experience
My research experiences span structural engineering, transportation systems, natural hazards, and community resilience. Through collaborations with researchers at the University of Nebraska-Lincoln and the University of Puerto Rico-Mayaguz, I have contributed to projects focused on infrastructure performance,, disaster risk reduction, transportation equity, emergency management, and post-disaster recovery.
Across these experiences, I have employed a variety of research methods including experimental testing, field and virtual reconnaissance, geographic information systems (GIS), literature reviews, interviews, probabilistic modeling, and strucutral reliability analysis. Together, these projects have shaped my interest in understanding how infrastructure and communities areaffected by natural hazards and how engineering research can support more resilient systems.
Wittich Research Group
University of Nebraska - Lincoln
About:
The Wittich Research Group, led by Dr. Christine E. Wittich in the Department of Civil and Environmental ENgineering at the University of Nebraska-Lincoln, conducts research aimed at improving the resilience of infrastructure and communities to natural hazards and extreme events. The group investigates how structures perform before, during, and after disasters, with an emphasis on understanding vulnerability, risk, recovery, and mitigation strategies. To address these challenges, the group integrates a variety of research approaches, including field and virtual reconnaissance, remote sensing, experimental testing, and analytical and probabilistic modeling.
Graduate Research Assistant
August 2021 - Present
My work can be broadly organized into four interconnected areas: Agricultural Infrastructure Performance, Structural Reliability and Fragility Analysis, Community Resilience and Recovery, and Disaster Data for Emergency Management.
Agricultural Infrastructure Performance Under Wind Hazards
Overview:
Extreme wind events such as hurricanes and derechos can cause significant damage to agricultural infrastructure, disrupting food production systems and threatening the economic stability of farming communities. Despite their importance, many agricultural structures have received limited attention in traditional structural engineering research, resulting in lack of vulnerability data and performance-based assessment tools.
This research focuses on understanding how agricultural infrastructure performs under extreme wind loading. Through digital reconnaissance, damage assessment, structural reliability analysis, and fragility modeling, the work seeks to quantify the vulnerability of systems such as center pivot irrigation systems, poultry houses, and grain storage facilities.
Research Activities:
-
Post-disaster grain bin damage assessments following the 2020 Midwest Derecho
-
Virtual reconnaissance of agricultural infrastructure following Hurricanes Idalia and Helene
-
Development of empirical fragility functions
-
Wind vulnerability assessment of poultry houses
-
Performance assessment of center pivot irrigation systems
-
Agricultural infrastructure damage databases
Outcomes:
"Virtual Reconnaissance and Fragility Analysis of Center Pivot Irrigation Systems and Poultry Houses Following Hurricane Idalia" - (Journal Article)
Authors:
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Christine E. Wittich
cwittich@unl.edu
Abstract:
Agricultural structures, including center pivot irrigation systems and poultry houses, are critical in sustaining food production and supporting the economy, particularly in the United States’ rural communities. The vulnerability of these structures to extreme wind events, such as hurricanes and derechos, can significantly disrupt agricultural operations, affecting food supply, local economies, and livelihoods. These structures are vital not only for the functioning of farms but are also deeply intertwined with the resilience of agricultural communities. Despite their importance, there is limited understanding of how these structures perform under extreme weather conditions and how their failure affects agricultural productivity, community recovery, and resilience. This paper investigates the impact of strong winds on center pivot irrigation systems and poultry houses, leveraging the event of Hurricane Idalia in northern Florida. A probabilistic analysis of post-event aerial imagery was performed to assess the damage to the agricultural structures and identify key variables correlated to their vulnerability. Notably, shorter center pivot irrigation systems have a higher probability of withstanding strong winds. Within the Hurricane Idalia dataset, longer poultry houses exhibited lower observed damage rates within construction-age groups; however, multivariate analysis indicates that wind speed and construction era are the most consistent predictors of damage probability, with geometric effects contributing more modest conditional influence. By quantifying the structural characteristics associated with reduced wind vulnerability, this paper provides evidence that can inform design improvements and targeted mitigation strategies to bolster the resilience of agricultural communities.
"Performance and Fragility of Agricultural Infrastructure after Hurricane Idalia" - (Conference Proceeding & Presentation)
Authors:
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Christine E. Wittich
cwittich@unl.edu
Abstract:
In the United States, agriculture is a major industry necessary for the economy and is particularly susceptible to damage from natural hazards like severe weather events (Walsh, M.K. et al. 2020), In 2022, the dollar amount from crop losses from hurricanes, hail, flooding, and other severe weather events totaled $1.08 billion (Munch, D. 2023). Furthermore, agricultural structures are routinely damaged in these events, impacting agricultural communities and individual farms more. On August 30th, 2023, Hurricane Idalia made landfall in northwest Florida. This storm significantly damaged thousands of agricultural structures, impacting many Floridian farms and the overall agricultural economy. This study aimed to investigate the damage caused by the storm, assess the failure patterns of the agricultural structures, and develop probabilisitic relationships to predict agricultural structure damage in future hurricanes for the first time. The structures included in this study were poultry houses and center pivot irrigation systems due to their prevalence in the region. A virtual reconnaissance from aerial imagery after the hurricane was analyzed to assess and categorize the damage to the structures. Defining characteristics of the structures were also collected as variables from GIS and parcel-level data sources. Correlations and Welch's t-tests for these variables were performed to understand their significance before developing probabilistic fragility functions relating the likelihood of damage to wind speed. Fragility analysis of center pivot irrigation systems indicated that longer structures have a much higher probability of failure than shorter structures. Meanwhile, the construction year was the most significant predictor of damage for poultry houses.
Structural Reliability and Fragility Analyses
Overview:
Engineering decisions are often made in the presence of uncertainty. Variability in hazard intensity, structural characteristics, material properties, and environmental conditions can significantly influence infrastructure performance during extreme events. Probabilistic methods provide a framework for quantifying these uncertainties and evaluating risk in a systematic manner.
This research applies reliability theory, uncertainty quantification, and probabilistic modeling to assess the performance of agricultural infrastructure exposed to wind hazards. Analytical and empirical approaches are used to develop fragility functions, estimate failure probabilities, and identify key factors influencing structural vulnerability.
Research Activities:
-
Empirical fragility development
-
Analytical fragility development
-
Monte Carlo Simulations
-
First-Order Reliability Method analyses
-
Reliability-based performance assessment
Outcomes:
"Probabilistic Assessment of Wind-Induced Overturnig of Center Pivot Irrigation Systems Using a Simplified Analytical Model" - (Conference Proceeding & Presentation)
Authors:
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Christine E. Wittich
cwittich@unl.edu
Milad Roohi
milad.roohi@unl.edu
Abstract:
Center pivot irrigation systems (CPIs) are critical components of agricultural production but are highly vulnerable to wind-induced damage due to their slender geometry, large footprint, and limited resistance to overturning. Despite their widespread use, quantitative tools for assessing their wind vulnerability under uncertainty remain limited. This study presents a simplified analytical model to evaluate the overturning reliability of individual center pivot irrigation spans subjected to wind loading. Each span is idealized as a rigid body resisting overturning through self-weight and experiencing wind-induced drag forces applied at an effective height. Uncertainty in geometric, mechanical, aerodynamic, and wind-related parameters is incorporated through probabilistic modeling. The analytical model is evaluated using Monte Carlo simulation, with reliability estimates verified using the First-Order Reliability Method (FORM). Fragility curves are developed from paired wind speed and failure outcomes and compared with empirical damage data from documented hurricane events. Results show that explicitly accounting for wind angle of incidence and operational weight conditions significantly influences predicted failure probabilities and improves agreement with empirical fragility trends. Overall, the simplified model effectively captures the key mechanics governing span-level overturning while remaining computationally efficient, thereby supporting its application in large-scale vulnerability assessments and resilience planning for agricultural infrastructure.
Farm Recovery and Community Resilience
Overview:
Natural hazards affect more than physical infrastructure. Damage to agricultural facilities can disrupt farm operations, reduce productivity, and create long-term challenges for rural communities that depend on agriculture as an economic driver. Understanding how farms recover after disasters is essential for improving resilience and reducing future losses.
This interdisciplinary research examines the relationship between infrastructure performance, farm recovery, and community resilience following windstorms. By integrating engineering assessments with surveys, stakeholder engagement, and resilience metrics, this work seeks to identify factors that influence recovery trajectories and inform strategies that strengthen the resilience of agricultural communities.
Research Activities:
-
Small farm recovery survey
-
Structural damage reference sheet
-
Functional recovery assessment
-
Community resilience analysis
-
Social vulnerability considerations
Outcomes:
“Driving Factors of Rural Social Vulnerability for Communities at High Risk of Riverine Flooding in the United States" - (Conference Proceeding and Poster Presentation)
Authors:
S. Yasaman Ahmadi
yahmadi2@huskers.unl.edu
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Christine E. Wittich
cwittich@unl.edu
Jeniffer I. Lather
lather@unl.edu
Abstract:
This paper examines the differences in factors of social vulnerability and flooding risk between rural and urban areas in the United States. Using data from the FEMA National Risk Index, US Census Bureau, CDC, and BRIC Community Resilience index, we analyze the relationship between overall riverine flood risk, social vulnerability, and community resilience and statistically significant differences are reported. Our findings show that rural counties with a high risk of riverine flooding have higher percentages of vulnerable populations, such as those living in poverty, without a high school diploma, over 65 years old, with disabilities, and living in mobile homes, compared to their urban counterparts. The work presents a timely and significant contribution to the field and provides a comprehensive snapshot of the national differences in community risk associated with flooding between rural and urban areas in the United States.
"Perceptions and Reality: Investigating the Effectiveness of Structural Enhancements in Steel Grain Bins against Wind Loads" - (Conference Proceeding)
Authors:
Christine E. Wittich
cwittich@unl.edu
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Andrew Ruder
aruder2@huskers.unl.edu
Maria K. Watson
maria.watson@ufl.edu
Rebekka Dudensing
rebekka.dudensing@ag.tamu.edu
Dean McCorkle
dean.mccorkle@ag.tamu.edu
Steven Klose
steven.klose@ag.tamu.edu
Abstract:
The August 2020 Iowa derecho resulted in significant damage to thousands of steel grain bins, impacting a significant portion of central and eastern Iowan farms. In the years since this storm, storage capacity of most farms has been regained and steel grain bins have been rebuilt. While the majority of bins have been replaced with bins of similar capacity, the structural design and construction varies between the original and replacement bins, which may or may not improve wind performance. This study aims to investigate trends in both perceived and realized structural enhancements of steel grain bins subjected to wind loads. The effect of various structural designs is evaluated using empirical fragility relationships, which yield a probability of damage given wind speed, as derived using damage observations in Iowa following the August 2020 storm and supplemented via finite element analysis. Trends associated with bin replacement are determined by longitudinal reconnaissance, in which follow-up trips to Iowa documented the construction of replaced bins. A structural enhancement factor is then computed for each bin replacement that indicates the increase (or decrease) in expected wind speed to cause damage. Perceptions regarding structural enhancement were gathered through a survey of farmers, in which farmers could indicate whether bins were/will be replaced with an upgraded construction. The perceptions from the survey and actual structural enhancement factor are analyzed and compared to determine if there is a correlation between farmers’ perceptions of structural enhancements with actual wind resistance.
"Vulnerability and Recovery of Small Farms Following Windstorms" - (Conference Proceeding)
Authors:
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Christine E. Wittich
cwittich@unl.edu
Maria K. Watson
maria.watson@ufl.edu
Rebekka Dudensing
rebekka.dudensing@ag.tamu.edu
Steven Klose
steven.klose@ag.tamu.edu
Dean McCorkle
dean.mccorkle@ag.tamu.edu
Abstract:
Despite the importance of U.S. agricultural production to national and global food security, relatively little is known about the disaster resilience of individual farms and agricultural rural communities. Resilience is a complex function of socio-economic dimensions and the built environment; and the population, economics, and physical infrastructure that comprise agricultural regions are distinct from the urban and suburban areas. There is a critical need to understand the complexities and key factors that contribute to agricultural disaster resilience. This research offers an overview and preliminary results from an ongoing project that aims to address this need, in part, by studying the vulnerability and recovery of farms following windstorms. The research team employed field and digital reconnaissance, web-based surveys, and interviews to assess the immediate impacts and recovery of farms following the 2020 Iowa Derecho, the 2022 Nebraska Windstorms, and the 2023 Hurricane Idalia. The study reveals the high vulnerability of physical infrastructure supporting agriculture to windstorms, identifying key structural variables predicting performance. Notably, the vulnerability of center pivot irrigation systems increases with length and initial orientation. Furthermore, farm recovery is a lengthy process and the majority of surveyed farms do not indicate that they have fully recovered two years after the storm. Among various factors influencing recovery, the shortage of builders emerged as the most frequently cited impediment. Future endeavors will aim to inform decision-making for enhancing resilience in farms and agricultural communities.
"Vulnerability and Recovery of Small Farms Following Windstorms" - (Conference Proceeding)
Authors:
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Chrystol Thomas
chrystol.thomas@ag.tamu.edu
Christine E. Wittich
cwittich@unl.edu
Maria K. Watson
maria.watson@ufl.edu
Steven Klose
steven.klose@ag.tamu.edu
Dean McCorkle
dean.mccorkle@ag.tamu.edu
Abstract:
Agricultural infrastructure on small farms, including metal buildings, grain bins, and center pivot irrigation systems, is often overlooked in discussions of natural hazard impacts. However, damage to these structures can significantly disrupt farm operations and local economies. This study examines the resilience of small farms after natural hazards by analyzing both the vulnerability and functionality recovery of two critical agricultural structures, namely center pivot irrigation systems and poultry houses, considering hurricane events. The study area selected was northern Florida, where Hurricane Idalia (2023) and Hurricane Helene (2024) caused widespread damage to farms and agricultural structures. Damage and recovery of agricultural structures were assessed using post-event aerial imagery. By evaluating failure rates and damage patterns for both types of structures after the events, fragility functions relating the probability of damage to windspeed were developed. Results emphasize the relatively low windspeeds at which damage to agricultural structures is likely to occur, as well as construction variables that are linked to higher probabilities of damage. Furthermore, results of the recovery analysis indicate that approximately 63% of center pivots irrigators and 32% of poultry houses damaged in Hurricane Idalia (2023) were repaired within one year but were subsequently damaged again in Hurricane Helene (2024). This study contributes to the knowledge of disaster resilience in agriculture and provides recommendations for future research directions aimed at safeguarding the agricultural sector and enhancing community resilience.
Leveraging Social Media Data for Emergency Preparedness and Response
NCHRP Synthesis 20-05/Topic 53-03
Overview:
Emergencies are often unpredictable, unique, and hard to track. Timely response to emergencies on highways is a critical issue faced by state departments of transportation (DOTs). State DOTs have been developing emergency response protocols and procedures. The popularity of social media provides an unprecedented opportunity for state DOTs to obtain information. Social media data provides vital spatial and temporal information before, during, and after emergencies and the use of social media is popular in emergency management for its high accessibility and effectiveness. Many DOTs have undergone technology renovations and have started using social media data for rapid emergency situation detection, damage assessment, and evacuation plan propagation. However, there is a lack of documentation of DOT practices of using social media and corresponding data under different emergency scenarios.
The objective of this synthesis is to document current state DOT practices that leverage social media data for emergency preparedness, response, and recovery.
Outcomes:
"NCHRP Synthesis 610: Leveraging Social Media Data for Emergency Preparedness and Response" - (Publication)
Authors:
Christine E. Wittich
cwittich@unl.edu
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Abstract:
Most state departments of transportation (DOTs) use social media to broadcast information and monitor emergencies, but few rely heavily on social media data. The most common barriers to using social media for emergencies are personnel availability and training, privacy issues, and data reliability. NCHRP Synthesis 610: Leveraging Social Media Data for Emergency Preparedness and Response, from TRB's National Cooperative Highway Research Program, documents state DOT practices that leverage social media data for emergency preparedness, response, and recovery.
"Barriers to Social Media use for Disasters within Transportation" - (Conference Proceeding & Presentation)
Authors:
Christine E. Wittich
cwittich@unl.edu
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
Abstract:
Transportation is a critical sector within emergency and disaster response; and, timely communication is necessary. Social media has gained popularity as both a means to communicate and to gather information during emergencies, however it is rarely leveraged to any significant extent within transportation. Given that some social media platforms have billions of active monthly users, the issue of barriers to leveraging this data source within transportation has been raised and is addressed within this study. The primary objective is to identify the most significant barriers to social media use before, during, and after emergencies within transportation agencies. A state-of-the-art review of social media use within transportation is first presented, in which situational awareness, natural language processing, and image-based machine learning techniques have emerged with transportation applications. This is supplemented by a survey that was conducted of transportation officials to gather insight into current use of social media data and perceived barriers within emergency contexts. Policies, information accessibility, and a lack of specialized tools emerge as common threads that prevent further implementation of social media within transportation. Recommendations are provided for further research to expedite implementation and to positively impact disaster response.
National Institute for Congestion Reduction
University of Puerto Rico - Mayagüez
Mission:
The National Institute for Congestion Reduction (NICR) will emerge as a national leader in providing multimodal congestion reduction strategies through real-world deployments that leverage advances in technology, big data science and innovative transportation options to optimize the efficiency and reliability of the transportation system for all users. Our efficient and effective delivery of an integrated research, education, workforce development and technology transfer program will be a model for the nation.
Enhancing Equity and Access for e-scooters
Research Assistant
March 2020 - May 2021
Principal Investigators:
Benjamín Colucci Ríos
benjamin.colucci1@upr.edu
Project Abstract:
This project will explore the distribution of new micro-mobility services, as well as the factors driving the demand, or lack thereof, of these services in heterogeneous neighborhoods. This project will focus on electric scooter (e-scooter) sharing services. The first e-scooter shared service in Puerto Rico was established by a private operator in the city of Mayaguez in August 2019. E-scooter services were subsequently established by the same company in the cities of San Germán and Río Piedras. The three cities differ in demographics, urban form, and topography. The main common characteristic of the three e-scooter service areas is the presence of a major university campus. E-scooter data will be collected from in-person surveys and from observational studies. Operational data will be requested to the e-scooter service provider to complement the research data collection efforts. Based on these data, statistical and machine learning-based models of the demand for this type of mobility service will be developed. The data and models can be used to: i) examine the equity implications of the e-scooter services implemented in Puerto Rico; ii) analyze the possible congestion reduction impacts of e-scooter shared systems; iii) and develop methods to optimize the spatiotemporal distribution of e-scooters based on equity considerations and congestion reduction potential.
Outcomes:
"User Characteristics, Spatiotemporal Patterns, and Spatial Access in a Dockless E-Scooter Service in Mayagüez, Puerto Rico" - (Conference Proceeding)
Authors:
Andrés G. Camacho Bonet
andres.camacho@upr.edu
Fernando A. Acosta Pérez
fernando.acosta@upr.edu
Lina M. Villa Zapata
lina.zapata@upr.edu
Gabriela Yáñez González
gabriela.yanez@upr.edu
Abstract:
A case study is presented of a dockless e-scooter system in Mayagüez, Puerto Rico. In addition to documenting the micromobility experience of a city within the understudied Latin American context, the study proposes methods to quantify spatial access to dockless micromobility systems, as well as to measure the regularity of their spatiotemporal patterns. Spatial access is measured in terms of network-level proximity to the e-scooter fleet, and the regularity of spatiotemporal patterns is assessed using a similarity measure approach. The study also includes an analysis of the attributes and opinions of users and nonusers of the e-scooter service, as collected through an online survey. The analysis suggests that, like in other cities, users of e-scooters tend to be male and young, and that nonusers tend to not participate in the system because of its cost and perceived safety concerns. Most users are students at the University of Puerto Rico at Mayagüez (UPRM). Trips starting or ending at UPRM accounted for 78% of all e-scooter trips, which are also closely linked to neighborhoods with a high concentration of UPRM students. In terms of temporal patterns, most e-scooter trips occur during weekdays, and the demand for the service drops significantly when UPRM is not in session. The service’s daily peak period occurs between 8:00 AM and 1:00 PM. The application of the proposed methods is illustrated using data from the considered system.
"Travel patterns and spatial access in a dockless e-scooter service in Puerto Rico" - (Publication)
Authors:
Daniel Rodriguez-Roman
daniel.rodriguez6@upr.edu
Alberto M. Figueroa Medina
alberto.figueroa3@upr.edu
Benjamín Colucci Ríos
benjamin.colucci1@upr.edu
Carlos A. Del Valle González
carlosa.delvallegonzalez@upr.edu
Andrés G. Camacho Bonet
andres.camacho@upr.edu
Fernando A. Acosta Pérez
fernando.acosta@upr.edu
Gabriela Yáñez González
gabriela.yanez@upr.edu
Abstract:
A case study is presented of a dockless e-scooter rental service (MDES) in Mayagüez, Puerto Rico, a city within the understudied Latin American region. MDES trip data were used to examine the spatiotemporal patterns of e-scooter trips in the city, while survey data was collected to explore the characteristics of MDES users and nonusers, as well as the factors that influenced their demand for MDES trips. In addition, this study proposes a network-based approach to evaluate the level of spatial access and equity of dockless micromobility vehicles. Three measures are proposed to quantify spatial access at the level of locations (i.e., network nodes) as a function of the distance of each location to each e-scooter. As illustrated in the MDES case, the measures can be used to examine spatial access at the service area-, zonal-, building-, and point-levels, and to compute spatial access inequality indexes. The survey analysis indicated that female respondents were 1.7 times less likely to use MDES than males and that young populations groups more than two times more likely to be MDES users than the reference population group. The survey analysis also revealed that cost, safety, and built environment concerns were the main barriers to the use of MDES, and that the primary reasons for using the service were parking problems and traffic congestion. Among other things, the spatiotemporal analysis of the MDES trips data shows that 78% of trips started and ended at the city’s main university, that a significant proportion of trips were linked to neighborhoods with a high concentration of university students, and that demand for e-scooter trips dropped drastically when the university was not in session. The analysis of the MDES data revealed marked differences in spatial access within and between zones in the study region. On average, daily Atkinson inequality index values, which were computed using the proposed spatial access indicators, ranged from 0.45 to 0.80, which points to an unequal spatial access to MDES. The paper closes by discussing applications of the proposed methodology for the design of policies aimed at minimizing inequality in spatial access to dockless micromobility services.
"Enhancing Equity and Access in Transportation Services" - (Oral Presentation)
Presenters:
Gabriela Yáñez González
gabriela.yanez@upr.edu
Charmelis Reyes Cruz
charmelis.reyes@upr.edu
Lina M. Villa Zapata
lina.zapata@upr.edu
Daniel Rodriguez-Roman
daniel.rodriguez6@upr.edu
Carlos A. Del Valle González
carlosa.delvallegonzalez@upr.edu
Benjamín Colucci Ríos
benjamin.colucci1@upr.edu
Alberto M. Figueroa Medina
alberto.figueroa3@upr.edu
Gallery:
2019 Summer Research Program
University of Nebraska - Lincoln
REU: Sustainability of Horizontal Civil Networks in Rural Areas
Research Affiliate
May 2019 - Aug 2019
About Program:
Rural areas, which contain approximately 20% of the US population and over 90% of the land area in the United States, are fundamental to human well-being in both rural and urban areas. Rural areas provide resources such as the infrastructure for U.S. food and bioenergy production, as well as the transportation infrastructure from inland urban centers to ports. Rural areas are characterized by agricultural- and natural resource-based economics, stable or declining populations with low population densities, and “farm-to-market” localized transportation patterns, and these characteristics necessitate new technologies and approaches for civil infrastructure. Despite the differences between rural and urban regions, little attention is paid to the unique challenges and opportunities for sustainability in rural areas.
In this ten-week summer research program, students work with faculty in the Department of Civil and Environmental Engineering to conduct research and contribute new knowledge to improve our understanding of how best to address the challenges facing rural environments. Through collaboration with industry partners, students also have opportunities to learn how infrastructure challenges are currently being addressed in the civil and environmental engineering industry. In addition, this program offers a series of communication development opportunities, including preparing a conference paper, giving informal presentations to peers, presenting formal posters, and reaching out to high school students.
Resilience of Agricultural Infrastructure and Rural Communities to Natural Hazards
Principal Investigator:
Significance:
Despite the criticality of the agricultural industry to both U.S. and global sustainable food production, the resulting lack of economic diversity in most rural areas is theorized to be a major contributor to the low resilience of rural communities to natural hazards, including earthquakes and windstorms. While resilience is a function of many socioeconomic and organizational factors, the disaster response of the built environment is a critical aspect that cannot be ignored. In many rural areas, critical infrastructure includes vital agricultural support and production systems, such steel grain bins. However, these structures are not typically design to consistent standards and have been observed to perform poorly in recent severe windstorms. This research aims to generate a fundamental understanding of the performance of steel grin bins during extreme windstorms to enhance rural resilience to natural hazards.
Outcomes:
"Resilience of Rural Infrastructure: Shake Table Tests of Scaled Silos" - (Poster Presentation)
Authors:
Christine E. Wittich
cwittich@unl.edu
Gabriela Yáñez González
gyanezgonzalez2@huskers.unl.edu
M. Khalid Saifullah
khalidsaif@huskers.unl.edu
Abstract:
In the United States, communities with a high agricultural economy, depend on unique infrastructures that complies with their needs. Earthquakes can cause great damage to these infrastructures and makes the recovery of the community harder. Some structures that support these communities do not follow typical engineering design and analysis methods. This paper examines the probabilistic response of steel storage silos to past earthquakes. Steel storage silos are thin-walled structures and are subject to buckling when excited by earthquake motions; however, many existing silos are also characterized by weak or no anchorage at the base, which enable the silo to uplift at its base and enter a rocking mode of response. Hence, an experimental campaign of shake table tests has been undertaken in order to probabilistically gauge the impact of material and geometric properties on the rocking response. A total of nine scaled structures, representative of a storage silo, were constructed for testing and were subjected to over 100 individual earthquake motions on the shake table to observe their response. Analysis of these results indicate that certain combinations of geometric and material properties yield systems likely to respond in pure rocking mode, while others result in combination modes and in overturning.
2019 Conference for Undergraduate Women in Physical Sciences (WoPhyS) at the University of Nebraska - Lincoln.
2019 UNL Summer Research Symposium
Gallery:
 |  |  |
|---|---|---|
 |  |