Rice University Research Repository
The Rice Research Repository (R-3) provides access to research produced at Rice University, including theses and dissertations, journal articles, research center publications, datasets, and academic journals. Managed by Fondren Library, R-3 is indexed by Google and Google Scholar, follows best practices for preservation, and provides DOIs to facilitate citation. Woodson Research Center collections, including Rice Images and Documents and the Task Force on Slavery, Segregation, and Racial Injustice, have moved here.
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Recent Submissions
Seismic Retrofitting of Low-Rise Reinforced Concrete (RC) Structures: a Multi-Faceted Evaluation
(2024-04-23) Laguerre, Marc-Ansy; Desroches, Reginald; Padgett, Jamie; Duno-Gottberg, Luis; Duenas-Osorio, Leonardo
The threat of seismic activity is a major concern for countries worldwide, and many have invested significant resources into researching the seismic retrofit of reinforced concrete (RC) structures. As a result, building codes and retrofit strategies have been enhanced to strengthen vulnerable structures. However, Haiti remains a country with limited knowledge about the vulnerability of RC buildings to seismic events and retrofitting solutions. This study aims to address this knowledge gap by conducting a comprehensive analysis of Haitian RC structures and evaluating multiple retrofit methods to enhance their seismic performance.
This study examines the retrofitting of RC buildings in Haiti using deterministic and probabilistic approaches, followed by a Life-Cycle Cost-Benefit (LCCB) analysis to determine the optimal techniques. The study first analyzes Haitian construction norms and practices before selecting building prototypes: R1 (residential 1-story), R2 (residential 2-story), NR2 (non-residential 2-story), and NR3 (non-residential 3-story). These prototypes' columns and beams are designed according to the BAEL (Beton Aux Etats Limites) guidelines, a French construction code widely used for engineered buildings in Haiti before 2010.
For the deterministic analysis, a two-phase numerical modeling method is used. Initially, continuum-based finite element models on LS-DYNA are used to validate and derive hysteretic curves of the column joints. Following this, a macroscopic model, which is calibrated from the results from LS-DYNA, is used for non-linear time history analysis of the building's 2D frames using OpenSees. Five retrofit strategies are then added to the original frames: RC shear walls (used for non-residential models), steel braces (used for residential models), buckling-restrained braces (used for non-residential models), prestressed tendons (used for residential models), and RC jackets (used for all models). These retrofits were designed such that the frames do not reach the life safety (LS) objectives of FEMA for a hazard of the return period of 2475 years. A total of 10 ground motions, which include motion recorded in Haiti, are chosen to run the time history analysis and evaluate the retrofit methods' efficiency. It was observed that the using of RC jackets with each of the global retrofits is able to enhance the building's performance to meet chosen performance objectives.
This research also assessed retrofitting solutions through probabilistic analysis, generating fragility curves. Initially, empirical fragility curves were derived using post-earthquake data and the shakemap from Haiti's 2021 earthquake, confirming the high vulnerability of Haitian RC buildings. Analytical fragility curves were subsequently developed for the four models representing these structures. Using continuum-based models on LS-DYNA, four damage states (minor, moderate, severe, and collapse) were used and investigated through pushover analyses. The results were then used for a multiple linear regression to predict the drift limit states. A probabilistic seismic demand regression was further derived via time history analysis on a 2D OpenSees model. The resulting analytical fragility curves revealed that incorporating RC jackets and a global retrofit substantially improved building resilience.
Finally, a LCCB analysis was conducted to assess the financial implications of the retrofits. By integrating hazard and fragility data with the estimated costs for building repair, replacement, and retrofitting, the benefit of implementing the retrofits was evaluated. The analysis revealed that retrofitting with RC jackets offers significant benefits. However, these benefits are notably higher when RC jackets are combined with steel braces in residential buildings, and with shear walls in non-residential buildings, thus optimizing the structural resilience and financial viability of the retrofitting strategies.
Unsettling Frontiers, Futures and Democracy: Alaska and Beyond
(2024-04-19) Haver, Maureen Siobhan; Boyer, Dominic
Alaska is frequently imagined by the Lower 48 as the Last Frontier, a vast pristine wilderness, and an essential component to United States energy independence. Alaska is also warming at twice the rate of the rest of the United States and is a contested site for oil and gas development in the Arctic. With over 222 million acres of land controlled by federal government—Alaska represents a third of all federal land holdings, reflecting the legacies of settler colonialism, the conservation movement, and resource extraction while raising questions about the future of decarbonization and decolonization amidst the climate crisis and Indigenous-led movements for sovereignty, climate justice, and land (Byrd 2011; Waziyatawin 2012; Estes 2019; Dhillon 2022). Through anthropological ethnography in Alaska and multidisciplinary research, this dissertation brings together climate, energy, and settler colonial studies to examine how the U.S. settler colonial project as a process of internal expansion enacted through reiterative and theoretical frontiers formed settler identities, notions of democracy and populism, and understandings of nature vis- à-vis resource abundance and extraction and the wilderness that impact the broader fights over public lands—which should also be understood as unceded Indigenous lands—decolonization, climate change, and energy transition.
Encapsulated Cell Systems for Treating Inflammatory Diseases
(2024-04-19) Aghlara-Fotovat, Samira; Veiseh, Omid; Ghanta, Ravi K
In response to pathogens and trauma, host immune cells interact bi-directionally with their local environment to receive and deposit molecular signals, which orchestrate cellular activation, proliferation, differentiation, and function to maintain healthy tissue homeostasis. While our immune system functions as a vigilant safeguard against environmental threats, instances of immune dysregulation may occur, leading to uncontrolled responses. In these conditions, it is essential to restore balance to the body through modulation of the immune system and the ECM. Cell-based therapeutics have significant potential in locally monitoring and treating inflammatory diseases, however, their widespread use is hindered by recognition and elimination by the host. Thus, novel technologies that can improve the viability and function of cell-based therapies have significant potential in improving translation. Here, we aim to utilize biomaterial encapsulation as a tool for improving the delivery of cell-based therapeutics for local immunomodulation in various inflammatory diseases including myocardial infarct, acute respiratory distress syndrome, neural inflammation, inflammatory bowel disease.
The Art of Politics and the Politics of Art
(Rice Design Alliance, 1994) Kalil, Susie
Travels in Large (and Small) Town Texas
(Rice Design Alliance, 1994) Quantrill, Malcolm