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Devin K. Harris

Publications and source records attributed to Devin K. Harris.

4 recordsLinked to original sources

Finite Element Model Updating-based Load Rating of Bridges with Incomplete As-Built Information

Load rating is the engineering process of determining the safe load-carrying capacity of an existing bridge structure often through analysis of its load-bearing members and their cross sections. However, when structural drawings and details of the structure are missing or insufficient for such calculations, alternative solutions must be used to infer the capacity. This study proposes a rational and consistent engineering solution for capacity inference based on structural identification (St-Id). The proposed approach uses finite element model updating (FEMU) to estimate the unknown characteristics of structures for use in an analytical load rating, which requires the development of an initial model developed in ABAQUS that can be updated based on experimental test data. ABAQUS allowed for the development of an interface with MATLAB, which facilitated the integration of an automatic iterative parameter optimization algorithm. The optimization algorithm developed in this investigation incorporated the features of a genetic algorithm (GA) and a gradient-based scheme to iterate on the unknown parameters. The proposed approach was evaluated on four in-service highway bridges including two concrete slab and two T-beam structures in varying deterioration condition states, which had sufficient plans available but were treated as having varying degrees of unknown details. The results illustrated that the finite element (FE) model updating approach generated load ratings that were within 0-17% of the target load ratings while alleviating the main challenges of the existing alternatives.

cs.CE

Computer Vision-Based Health Monitoring of Mecklenburg Bridge Using 3D Digital Image Correlation

A collaborative investigation between the University of Virginia (UVA) and the Virginia Transportation Research Council was performed on the Mecklenburg Bridge (I-85 over Route 1 in Mecklenburg County). The research team aided the Virginia Department of Transportation - Richmond District in the characterization of the bridge behavior of one of the bridge beams that had been repaired due to a previous web buckling and crippling failure. The investigation focused on collecting full-field three-dimensional digital image correlation (3D-DIC) deformation measurements during the dropping sequence (removal of jacking to support beam on bearing/pier). Additionally, measurements were taken of the section prior to and after dropping using a handheld laser scanner to assess the potential of lateral deformation or out-of-plane buckling. Results from the study demonstrated that buckling of the tested beam did not occur, but did provided a series of approaches that can be used to evaluate the effectiveness of repaired steel beam ends. Specifically, the results provided an approach that could estimate the dead load distribution through back-calculation.

eess.IV

In-service performance and behavior characterization of the hybrid composite bridge system - a case study

The Hybrid Composite Beam (HCB) system is an innovative structural technology that has been recently used in bridge construction within the U.S. transportation network. In this system, the superstructure consists of a conventional reinforced concrete deck supported by Hybrid Composite Beams. Each beam is comprised of a glassfiber reinforced polymer (FRP) box shell containing a tied parabolic concrete arch. Inclined stirrups provide shear integrity and enforce composite action between the HCBs and the concrete deck. This paper focuses on evaluating the in-service performance of a newly constructed HCB bridge superstructure located on Route 205 in Colonial Beach, Virginia. A live load test was conducted using tandem axle dump trucks under both quasi-static and dynamic conditions. Results obtained from the experimental investigation were used to determine three key behavior characteristics. Dynamic amplification and lateral load distribution were found to be reasonable in comparison to the assumed design values. The testing program also included internal and external measurement systems to help characterize the load sharing behavior of the HCB on an element level. The main load carrying elements are the deck in compression and the steel ties in tension, and the FRP shell did not act compositely with the internal components.

physics.gen-ph

Effect of Deck Deterioration on Overall System Behavior, Resilience and Remaining Life of Composite Steel Girder Bridges

During past few decades, several studies have been conducted to characterize the performance of in-service girder-type bridge superstructures under operating conditions. Few of these efforts have focused on evaluating the actual response of the bridge systems, especially beyond the elastic limit of their behavior, and correlating the impact of damage to the overall system behavior. In practice, most of the in-service bridge superstructures behave elastically under the routine daily traffic; however, existing damage and deteriorating conditions would significantly influence different aspects of the structural performance including reserve capacity, resilience and remaining service-life. The main purpose of this study is to evaluate the response of composite steel girder bridges under the effect of subsurface delamination in the reinforced concrete deck. Commercial finite element computer software, ANSYS, was implemented to perform a nonlinear analysis on a representative single-span simply supported bridge superstructure. The system failure characteristics were captured in the numerical models by incorporating different sources of material non-linearities including cracking/crushing in the concrete and plasticity in steel components. Upon validation, non-linear behavior of the system with both intact and degraded configurations was used to evaluate the impact of integrated damage mechanism on the overall system performance. Reserve capacity of this bridge superstructure was also determined with respect to the nominal element-level design capacity. As vision to the future path, this framework can be implemented to evaluate the performance of other in-service bridges degraded under the effect of different damage scenarios, thus providing a mechanism to determine a measure of capacity, resilience and remaining service-life.

math.NA