Material Structural Deficiencies of Road Bridges in the U.S.

Abstract

This study analyzes the National Bridge Inventory in the U.S. to determine the relative structural deficiencies of bridge materials, comparing between the overall national values and each state, geographically. The analysis considers the most common bridge construction materials-concrete, steel, and prestressed/post-tensioned concrete. The results suggest need to reassess the efficacy of best performance practices for steel bridges and for states with structural deficiencies above the national average. Geographic consistency of structurally deficient bridge density with population density shows need to improve intervention strategies for regions with higher levels of service usage. The study also compares the relative operational lifespan of bridge materials in each state. The average structurally deficient bridge ages are lower than the 75-year life-cycle expectancy. Prestressed/post-tensioned concrete bridges reveal relatively lower lifespan. Over time, concrete and steel bridges show some gradual improvement with decreasing percentage of structural deficiency and increasing lifespan. Prestressed/post-tensioned concrete bridges reveal shifting earlier accumulation of structural deficiency for a particular age group. The study also reveals relative climate effects. Climate conditions correlate differently with the structural deficiency and life cycle of bridge materials in each state. Structurally deficient bridge densities show correlation with climate maps, especially under colder and moist conditions.

Two-Dimensional Mechano-thermoelectric Heterojunctions for Self-Powered Strain Sensors

“…Structural health monitoring (SHM) is the process of detecting damage in buildings, bridges, and other engineering structures. Different from other emerging sensing applications, such as wearable health electronics, SHM represents a mature market of 1.6 billion dollars in 2019 that becomes more important as infrastructure keeps aging . Previous work has identified the combination of thermoelectric energy harvesting and electric strain sensing as the most promising approach for SHM due to the robustness, ease of deployment, and low cost.…”

“…Different from other emerging sensing applications, such as wearable health electronics, SHM represents a mature market of 1.6 billion dollars in 2019 that becomes more important as infrastructure keeps aging. 10 Previous work has identified the combination of thermoelectric energy harvesting and electric strain sensing as the most promising approach for SHM due to the robustness, ease of deployment, and low cost. We demonstrate multifunctionality in SnSe 2 /graphene heterojunctions that overcomes previous issues of low available power density, 11 high required sensing resolution, 12 and challenges in miniaturization and opens up a route for future ubiquitous smart devices.…”

Überführbarkeit der Eingangsgrößen von Lebenszykluskostenanalysen bei Massivbrücken

“…Ein funktionaler Zusammenhang zwischen Zustandsklasse und Bauwerksalter wird in zahlreichen Veröffentlichungen formuliert [27–32]. Der funktionale Zusammenhang ist teilweise linear, teilweise nichtlinear.…”