Infrastructure as Institutional Relics: Insights from the United States Bridge System
Creators: name: Jaison Desai
Publisher: name: Carnegie Mellon University
Year: 2018
Subjects: subject: 160510 Public Policy
subject: FOS: Political science
subject: FOS: Political science

description: This thesis considers challenges with infrastructure management at the nexus of sociology and engineering. Why do we continue to struggle with the management of deteriorating infrastructure systems when capable engineering systems exist for monitoring, identifying, and<br>prioritizing facets of these systems? The prevailing view of infrastructure systems assumes that they are exogenous to society and thus largely focus on the social impacts of the technical facets of such systems (infrastructure → society). Utilizing institutional theory, science and technology<br>studies, and social movement theory, this thesis advances the perspective that social factors have an influence on the technical parameters of infrastructure systems; infrastructure is therefore endogenous to society (society → infrastructure). The interplay between social and technical<br>factors is explored through three complementary sections using a variety of statistical methods and 21 years of data from the National Bridge Inventory (NBI) of the United States Federal Highway Administration (FHWA) and other sources.<br>The first paper explores the institutional constraints that inhibit bridge managers from addressing challenges with remediation of outdated bridges. More specifically, it depicts bridges as institutional relics, whereby a bridge’s physical attributes reflect the accepted standards of the<br>time and later persist even when those standards may change. Bridges are more likely to be institutional relics when built prior to the adoption of national design mandates (regulative-based relics) or in locales whose engineering norms conflict with these national standards (normativebased relics). Bridge ownership and the spatial constraints present in more urban settings moderate the ability of bridge managers to address those bridges that are identified as relics. The second paper focuses on the role of attachment to institutional relics and its potential to<br>inspire collective action around preserving them. Specifically, it considers movements to enroll bridges into the National Register of Historic Places (NRHP) on closure rates and subsequent sufficiency. Not only do bridges enrolled on the NRHP have a lower risk of closure in postenrollment<br>years as compared to similar non-enrolled bridges, but these movements also restrict engineering options on enrolled bridges, with improvements focused on non-historic elements (i.e. the bridge’s substructure). This informs social movement research by considering movements of preservation instead of change and how movements can directly influence the built environment as an end goal.<br>In the third paper, bridge sufficiency is considered through the lens of inspection data to identify influential attributes affecting monitoring of potential institutional relics. A framework is developed for providing feedback to bridge managers, designers, and policymakers. Given<br>computation challenges, previous studies understandably and necessarily begin with a limited scope, data, or variable selection. This study leverages novel computational techniques, namely a least absolute shrinkage and selection operator (LASSO) approach, that can more<br>comprehensively consider the entire United States bridge system and its variables to inform attribute selection. It finds that a mixture of inspector-driven variables, design/maintenance variables, and weather are highly influential in calculating overall bridge sufficiency rating.<br>Many of the factors that persistently influence bridge sufficiency are also related to social challenges, namely the presence of institutional relics, explored previously. As such, this paper presents one possible computational approach for scoping the most salient technical and social<br>variables for which bridge designers and managers should focus attention when seeking to monitor bridge deterioration. These results are then tied to contemporary issues in bridge management and used to propose policy actions within each section of findings to better address bridge management issues. In sum, this thesis helps advance a more sociological understanding toward infrastructure, namely how social parameters can influence engineering systems, as applied in the context of bridge<br>systems. <br>