Bridges are assets in every society, and their deterioration can have severe economic, social, and environmental consequences. Therefore, implementing effective asset management strategies is crucial to ensure bridge infrastructure’s long-term performance and safety. Roadmaps can serve as valuable tools for bridge asset managers, helping bridge engineers make informed decisions that enhance bridge safety while maintaining controlled life cycle costs. Although some bridge asset management roadmaps exist, such as the one published by the United States Federal Highway Administration (FHWA), there is a lack of structured research roadmaps that are both region-specific and adaptable as guiding frameworks for similar studies. For instance, the FHWA roadmap cannot be universally applied across diverse regional contexts. This study addresses this critical gap by developing a research roadmap tailored to Idaho, USA. The roadmap was developed using a three-phase methodological approach: (1) a comprehensive analysis of past and ongoing Department of Transportation (DOT)-funded research projects over the last five years, (2) a nationwide survey of DOT funding and research practices, and (3) a detailed assessment of Idaho Transportation Department (ITD) deficiently rated bridge inventory, including individual element condition states. In the first phase, three filtering stages were implemented to identify the top 25 state projects. A literature review was conducted for each project to provide ITD’s Technical Advisory Committee (TAC) members with insights into research undertaken by various state DOTs. Moreover, in the second phase, approximately six questionnaires were designed and distributed to other state DOTs. These questionnaires primarily covered topics related to bridge research priorities and funding allocation. In the final phase, a condition state analysis was conducted using data-driven methods. Key findings from this three-phase methodological approach highlight that ultra-high-performance concrete (UHPC), bridge deck preservation, and maintenance strategies are high-priority research areas across many DOTs. Furthermore, according to the DOT responses, funding is most commonly allocated to projects related to superstructure and deck elements. Finally, ITD found that the most deficient elements in Idaho bridges are reinforced concrete abutments, reinforced concrete pile caps and footings, reinforced concrete pier walls, and movable bearing systems. These findings were integrated with insights from ITD’s TAC to generate a prioritized list of 23 high-impact research topics aligned with Idaho’s specific needs and priorities. From this list, the top six topics were selected for further investigation. By adopting this strategic approach, ITD aims to enhance the efficiency and effectiveness of its bridge-related research efforts, ultimately contributing to safer and more resilient transportation infrastructure. This paper could be a helpful resource for other DOTs seeking a systematic approach to addressing their bridge research needs.

The objective of this study is to develop failure-limit material models for Aluminum 6061-T6, A36 Carbon Steel, 304 Stainless Steel, and Nitronic 60 metals, based on parameters of plastic equivalent strain (failure strain) and stress triaxiality. The research is conducted in two parts. This paper presents Part One of the study. In Part One, custom-designed test specimens undergo controlled uniaxial tension and compression testing at ambient temperature. These tests are performed at quasi-static speeds using Universal Testing Machines (UTMs) in accordance with ASTM E8 and ASTM E9 standards. Experimental data, specifically engineering stress–strain and force–displacement curves, are recorded from the onset of loading until specimen fracture, or in the case of compression tests, until the capacity of the testing machine is reached. In Part Two, the emphasis shifts to the calibration of Finite Element Analysis (FEA) models of the custom-designed test specimens. Plastic equivalent strain and the corresponding stress triaxiality values at failure are extracted from each test specimen for the given metal. These values are then systematically plotted onto a single graph to construct the failure-limit curve, which delineates the boundary conditions for material failure. This approach will facilitate the development of a comprehensive material property definition that correlates plastic equivalent strain with stress triaxiality at failure for Aluminum 6061-T6, A36 Carbon Steel, 304 Stainless Steel, and Nitronic 60 metals.

Accelerated Bridge Construction (ABC) can be defined as the process of prefabricating bridge elements in a factory, then transporting the components to the bridge site for subsequent assembly. ABC offers rapid construction, minimum traffic disruption, better quality control, improved work zone safety, maximum use of machinery, durability of bridge components, and less environmental impacts.ABC is becoming a popular construction technique in the United States, Japan, New Zealand, and Europe. This paper begins with a literature review of the recent developments in ABC in the United States and New Zealand. It highlights past and recent applications of ABC in the State of Idaho including several bridge projects from the Idaho Department of Transportation (ITD) where incorporated ABC technologies are discussed.A summary of the past research project on ABC at Idaho State University (ISU) is presented. This project investigated use of grouted splice coupler for column-to-footing and column-to-cap beam connections in regions of high seismicity in Idaho. The paper also presents an overview of an on-going research project on ABC that is funded by ITD and ISU (2017-2018). The project has experimental and analytical parts which investigate properties and performance of closure-pour materials between pretensioned Deck Bulb-T girders. The first phase of the project focuses on development of an optimum cost-effective closure-pour mix that would possess not only sufficient structural properties, but also would be durable and require lower maintenance. In the second phase of project, the structural performance of the closure-pour materials would be investigated experimentally using several beams. A typical beam specimen would represent a transverse strip of the superstructure composed of precast girders on sides and closure-pour in the middle. Results from experimental testing would be used in the third phase to create analytical models of the proposed closure-pour details. The models would be capable of assessing the connection strength under one-time truck load, providing an indication of fatigue performance under repeated loading, and indicating durability performance such as crack control and interface bond.

This project focuses on the retrofitting of concrete bridge piers. In the first phase of the project, a half-scale bridge bent was designed and experimentally tested in the Idaho State University (ISU) Structural Lab (SLAB) under earthquake-style loading. The bents modeled a pier connection developed by ISU and Idaho Transportation Department (ITD) (pipe-socket connection). The bridge bent was tested until failure and the results were processed and compared to one another. After testing the bent specimens ISU and ITD have come back to work on another project to retrofit the half-scale bridge piers and experimentally test and quantify the design. Many post-earthquake repair methods have been suggested by ISU and ITD to repair the pier's stiffness, strength, and ductility after a design-level event. This paper focuses on ultra-high-performance concrete (UHPC) jacketing as the retrofit method. Methods to retrofit concrete-filled steel tubes (CFSTs) have only been used in analytical studies and have not been experimentally tested. In order to combat this issue of lack of experimental data, ISU is testing four piers with a UHPC jacket retrofit. The objective of this research is to experimentally validate the proposed UHPC retrofit for the pipe connection.