Monitoring of an Interstate-25 High Performance Concrete Bridge with an Embedded Optical Fiber Sensor System

Monitoring of an Interstate-25 High Performance Concrete Bridge with an Embedded Optical Fiber Sensor System
Author: Rola Labban Idriss
Publisher:
Total Pages: 223
Release: 2009
Genre: Concrete bridges
ISBN:

The I-25/Dona Ana Interchange in Las Cruces NM is a simple span, high performance concrete (HPC)prestressed girder bridge. The girders are six prestressed, BT-63 HPC girders with a span length of 112.5 ft (34.2 m). The bridge was monitored from fabrication through service with an embedded optical fiber sensor system. Thirty two Fiber Bragg Grating (FBG) optical fiber deformation sensors were installed in the beams during fabrication. The strands were 6/10 inch ( 1.5 cm ) low relaxation strands and the concrete had a design compressive strength of 8 ksi (55.2 MPa) at release and 9.5 ksi (66.5 MPa) at 28 days. The bridge was monitored for two years, from transfer of the prestressing force through service. Several topics that are studied in this project: prestress losses, camber, shear and moment girder distribution factors, impact factor, insitu material properties and serviceability under traffic loads. The results from sensor measurements were compared to the values predicted by the AASTHO codes and other design codes or empirical equations, to check the accuracy of these codes when applied to HPC girder bridges.

Preliminary Results on the Monitoring of an In-Service Bridge Using a 32-Channel Fiber Bragg Grating Sensor System

Preliminary Results on the Monitoring of an In-Service Bridge Using a 32-Channel Fiber Bragg Grating Sensor System
Author: S. Vohra
Publisher:
Total Pages: 24
Release: 1998
Genre:
ISBN:

This report describes the preliminary results of the performance of a 32-channel fiber Bragg grating (FBG) system used to monitor the dynamic response of an in-service interstate bridge (North-bound span, 1-10 at University Blvd., Las Cruces, New Mexico). Fiber Bragg grating sensors were attached on four different support girders in groups of three at various locations along the span of the bridge. Using an interrogation approach based on the scanning Fabry-Perot system, the sensors were monitored for various vehicle loading conditions. They dynamic response of the bridge to a typical traffic load event as detected by a group of three sensors on a particular girder is illustrated in some detail by describing the data both in time and frequency domains. This is followed by a description of the response of all 32 sensors on the bridge to two traffic loading events. The field test results indicate that the natural resonant frequencies of the first two longitudinal modes of the bridge are 2.5 Hz and 3.8 Hz, respectively. The preliminary results reported here clearly demonstrate that an optical FBG sensor system is ideally suited for monitoring weigh-in-motion traffic events as well as for providing the dynamic properties of bridge structures.

Remote Continuous Evaluation of a Bridge Constructed Using High Performance Steel

Remote Continuous Evaluation of a Bridge Constructed Using High Performance Steel
Author: Terry J. Wipf
Publisher:
Total Pages: 146
Release: 2006
Genre: Iron and steel bridges
ISBN:

Of the approximately 25,000 bridges in Iowa, 28% are classified as structurally deficient, functionally obsolete, or both. The state of Iowa thus follows the national trend of an aging infrastructure in dire need of repair or replacement with a relatively limited funding base. Therefore, there is a need to develop new materials with properties that may lead to longer life spans and reduced life-cycle costs. In addition, new methods for determining the condition of structures are needed to monitor the structures effectively and identify when the useful life of the structure has expired or other maintenance is needed. High-performance steel (HPS) has emerged as a material with enhanced weldability, weathering capabilities, and fracture toughness compared to conventional structural steels. In 2004, the Iowa Department of Transportation opened Iowa's first HPS girder bridge, the East 12th Street Bridge over I-235 in Des Moines, IA. The objective of this project was to evaluate HPS as a viable option for use in Iowa bridges with a continuous structural health monitoring (SHM) system. The scope of the project included documenting the construction of the East 12th Street Bridge and concurrently developing a remote, continuous SHM system using fiber-optic sensing technology to evaluate the structural performance of the bridge. The SHM system included bridge evaluation parameters, similar to design parameters used by bridge engineers, for evaluating the structure. Through the successful completion of this project, a baseline of bridge performance was established that can be used for continued long-term monitoring of the structure. In general, the structural performance of the HPS bridge exceeded the design parameters and is performing well. Although some problems were encountered with the SHM system, the system functions well and recommendations for improving the system have been made.

The Design and Implementation of a Sensor Network System for Concrete Bridge Health Monitoring

The Design and Implementation of a Sensor Network System for Concrete Bridge Health Monitoring
Author: Joseph John Barbera
Publisher:
Total Pages: 514
Release: 2009
Genre: Concrete bridges
ISBN:

A bridge health monitoring system for bridge deck condition assessment was designed and developed for short and long term static analysis. This system was composed of a remotely accessible on-site data acquisition system and vibrating wire strain gauges to monitor both strain and temperature over given time increments. The system relied on a redundant embedded sensor network in a concrete bridge deck to collect and provide static performance data under different loading conditions in order to provide reliable assessment by collecting, storing, analyzing, and reporting data related to the condition of the bridge over time. A case study will be used for evaluating the system. The bridge used in this case study is the Parkview Bridge that was recently constructed over U.S. 131 in Kalamazoo, Michigan.

Diagnostic and Proof Load Testing of NM Bridge 9706 Using High Performance and Locally Developed Ultra High Performance Concrete Girders

Diagnostic and Proof Load Testing of NM Bridge 9706 Using High Performance and Locally Developed Ultra High Performance Concrete Girders
Author: Chris S. Kennedy
Publisher:
Total Pages: 462
Release: 2018
Genre:
ISBN:

Recent research at New Mexico State University (NMSU) has led to the development of unique Ultra High Performance Concrete (UHPC) mixture proportions. Utilizing constituents typical of precast production and primarily local to New Mexico, as well as high strength steel fiber reinforcement, these mixture proportions exhibit the advanced characteristics typical of commercially available UHPC. Providing an economic alternative to commercially available products, NMSU's research of non-proprietary UHPC focuses on the mixture optimization, material behavior, and full-scale implementation for structural applications. The research presented in this thesis focuses on the load testing of a newly constructed local bridge in Anthony, New Mexico. Bridge 9706 has a two-span superstructure comprised of a non-proprietary UHPC span and conventional high performance concrete (HPC) span. The bridge girders were fabricated at a region precast plant in New Mexico, using previously developed batching and curing procedures. The fabrication process aided in familiarizing precasters with the production of UHPC and helps to promote further implementation of UHPC in local production and design. After construction, Bridge 9706 was tested with a diagnostic load test and proof load test to investigate the behavior and performance of the bridge. Through comparative analyses of the two-span bridge, evidence of the advanced characteristics and performance of UHPC versus HPC are provided. Additional design recommendations are addressed for the promotion of UHPC for structural applications.

Phonetics, Theory and Application

Phonetics, Theory and Application
Author: William R. Tiffany
Publisher: McGraw-Hill Humanities, Social Sciences & World Languages
Total Pages: 456
Release: 1977
Genre: Language Arts & Disciplines
ISBN: