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Description: A .rar folder with data files for the project on "Minimizing Shrinkage, Creep and Cracking Damage to Concrete Bridges", 2010. Keyword: Dataset Creator: Guang-Hua Li Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/22/2017 Date Modified: 06/22/2017 Date Created: 2008 Rights: All rights reserved Resource Type: Dataset -
Relaxation Database v1.1
Description: An .xls file with data for the project on "Minimizing Shrinkage, Creep and Cracking Damage to Concrete Bridges (A423, A447)", 2010. Keyword: Dataset Creator: Kyung-Tae Kim Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/22/2017 Date Modified: 06/22/2017 Date Created: 2010 Rights: All rights reserved Resource Type: Dataset -
Database of Slender Beam with Stirrups
Description: An .xls file with data for the project on "Minimizing Shrinkage, Creep and Cracking Damage to Concrete Bridges (A423, A447)", 2010. Keyword: Dataset Creator: Qiang Yu Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/22/2017 Date Modified: 06/22/2017 Date Created: 2010 Rights: All rights reserved Resource Type: Dataset -
Creep Database v1.1
Description: An .xls file with data for the project on "Minimizing Shrinkage, Creep and Cracking Damage to Concrete Bridges (A423, A447)", 2010. Keyword: Dataset Creator: Kyung-Tae Kim Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/22/2017 Date Modified: 06/22/2017 Date Created: 2010 Rights: All rights reserved Resource Type: Dataset -
Stray Current Corrosion in Electrified Rail Systems
Description: Despite a relatively mature technology for its control, corrosion caused by stray current from electrified rapid-transit systems costs the United States approximately $500 million annually. Part of that cost is the result of corrosion of the electrified rapid-transit system itself, and part is the result of corrosion on neighboring infrastructure components, such as buried pipelines and cables. Detailed costs to either the transit systems or the neighboring infrastructure are not available, and, therefore, this limited study was undertaken for the Infrastructure Technology Institute (1) to assess the scope of stray-current corrosion on the electrified-rail systems based upon information in the literature and from interviews with selected transit-system operators, and (2) to determine whether new or additional corrosion monitoring or mitigation techniques are needed. The literature review was conducted through the Infrastructure Technology Institute Library Services Program, the Transportation Library, and the Seeley G. Mudd Library for Science and Engineering, all at Northwestern University. The interviews were conducted with seven rapid-transit operators, which included the following: (l) Chicago Transit Authority, (2) Port Authority Trans-Hudson Corporation, (3) Metro-North Commuter Railroad Metropolitan Transportation Authority, (4) New York City Transit Authority Metropolitan Transportation Authority, (5) San Francisco Bay Area Rapid Transit District, (6) Los Angeles County Metropolitan Transportation Authority, and (7) West Virginia University-Morgantown Personal Rapid Transit System. Keyword: Stray current corrosion Creator: Barlo, Thomas J. and Zdunek, Alan D. Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/22/2017 Date Modified: 06/22/2017 Date Created: 1995-05 Rights: All rights reserved Resource Type: Report -
Structural integrity assessment on pin and hanger connection of aging highway bridges using finite element analysis
Description: The finite element method is used to investigate failure mechanisms in pin-hanger connection in aging highway bridges. Bridge pins and hangers are typically considered as critical elements whose failure may result in partial or entire collapse of the structure. The primary function of a pin-hanger connection is to allow for longitudinal thermal expansion and thermal contraction in the bridge super-structure due to temperature changes (daily or seasonal). The induced movements, due to thermal effects, have considerable impact on bridge design and performance. Thus, in addition to the applied mechanical loads (dead load and traffic), the thermal load due to temperature changes is also included. A key goal was also to relate original design calculations (before the bridge was built) to the current analysis which accounts for the entire bridge structure under combined loads and extreme environmental conditions. Many bridges in use today have deteriorated due to aging, misuse, or lack of proper maintenance. After years of exposure to atmospheric environments (deicing salts and load variations), corrosion and wear tend to produce at least a partially fixed (or locked up) condition. Pack-rust (or corrosion buildup) can have two detrimental effects on the pin: • First, the cross-section of the pin can “decrease” because of corrosive section loss. The corrosion can produce pitting that may act as crack initiation sites. • Second, pack-rust can effectively “lock” the pin within the connection, so that no rotation is permitted. This may produce a likely location for the development and propagation of cracks. Furthermore, bridge structure is nonlinear especially when the pin is in the locked condition and an elastic-plastic analysis is required to model the bridge behavior when the pin is locked. One of the main focuses in this study is on the determination of the three-dimensional (3D) crack growth in the pin, since the lifetime of the entire structure is dependent on the behavior of cracks. Due to the accessibility of 3D finite element programs and the comparatively low cost of computing time, it is state of the art to perform 3D analyses of complex engineering problems. The finite element program ABAQUS has been used throughout the investigation, which essentially includes: • stress analysis • thermal effects • elastic-plastic analysis • determination of the mixed-mode stress intensity factors (KI , KII , and KIII ) • fatigue crack growth simulation Furthermore, since analytical solutions are not available in many cases, especially for this 3D problem (with complex geometry and loading conditions), a series of validation tests were performed on bridge components. Keyword: Structural integrity assessment Creator: Houcque, David Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/22/2017 Date Modified: 06/22/2017 Date Created: 2008-06 Rights: All rights reserved Resource Type: Dissertation -
Acoustic Emission Monitoring of North East Trunnion Shaft on Oregon DOT Bridge 1377A: I-5 over the Columbia River, Portland, Oregon
Description: This report shows the results of acoustic emission (AE) monitoring, and provides additional information on the nature of the ultrasonic indications in the north east trunnion shaft. Keyword: Acoustic emission testing Creator: Prine, David W. and Oleksy, Jerome E. Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/21/2017 Date Modified: 06/21/2017 Date Created: 1996-05 Rights: All rights reserved Resource Type: Report -
Remote Global Monitoring of the Michigan Street Bridge, Sturgeon Bay, Wisconsin
Description: A remote global monitoring system is being operated on a 65 year old lift bridge in Sturgeon Bay Wisconsin. The system uses both strain gages and clinometers to continuously monitor the "health" of the fracture critical components of the bridge. Ruggedized miniaturized data loggers are locally mounted on the structure at the individual test sites. Spread spectrum RF links network the individual data logger computers to a central host computer. The host computer is connected to a dedicated telephone line via modem to allow remote access to the recorded data as well as real time monitoring capabilities. This system uses commercially available equipment. It provides a practical cost effective solution to a problem that is not unique to this structure, the need for intensive continuous monitoring to assure safe operation of aging structures during life extension. Keyword: Acoustic emission testing Creator: Fish, Philip and Prine, David Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/21/2017 Date Modified: 06/21/2017 Date Created: 1997 Rights: All rights reserved Resource Type: Report -
Application of Acoustic, Strain, and Optical Sensors to NDE of Steel Highway Bridges
Description: Current bridge condition determination is based almost entirely on the use of visual inspection. This approach to bridge inspection provides data that is subjective and not traceable. Nondestructive evaluation (NDE) is a tool that in actuality is little used on bridges, but could eliminate much of the subjectivity of the input data for the bridge condition determination. A critical task for NDE on these structures is to detect and locate flaws that are growing which may eventually lead to serious impairment of the structures ability to perform its designed function. This problem area is the focus for a bridge NDE program currently being conducted by Northwestern's Infrastructure Technology Institute, (ITI). Under this program, all elements of the bridge inspection problem are being investigated by an interdisciplinary group consisting of members of Northwestern's faculty and BIRL staff. One of the major research areas of the program is the application of acoustic emission (AE) monitoring to steel bridges. AE monitoring is being combined with strain and optical sensors to develop a practical bridge inspection tool. This paper will present the latest results of field tests conducted recently on bridges in California and Wisconsin. Keyword: Acoustic emission testing Creator: Prine, David Owner: Nurganym Agzamova Publisher: Northwestern University Libraries Language: English Date Uploaded: 06/21/2017 Date Modified: 06/21/2017 Date Created: 1995-05 Rights: All rights reserved Resource Type: Report -
Acoustic emission and strain gage monitoring of prototype retrofit for Caltrans Structure B-22-26 R/L, I-80 Sacramento River (Bryte Bend), Sacramento, California.
Description: This technical report shows the findings of acoustic emission and strain gage monitoring tests conducted by research engineers of Infrastructure Technology Institute from Northwestern University on April 18, 1997 in Sacramento, California. Keyword: Acoustic emission testing Creator: Marron, Daniel and Prine, David W. Owner: Nurganym Agzamova Language: English Date Uploaded: 06/21/2017 Date Modified: 06/21/2017 Date Created: 1997-04-18 Rights: All rights reserved Resource Type: Report