Engineering Commons^™

Identification Of Bridges With Fracture-Prone Details, Theodore Hopwood Ii, Rick Younce, Sudhir Palle

Kentucky Transportation Center Research Report

Welded steel girder bridges can contain details that can high welding and service stresses and are termed constraintinduced fractures (CIF). The Kentucky Transportation Cabinet has steel bridges with weld details known to cause CIFs whose girders have experienced fracture events. The Cabinet’s bridge inventory was reviewed and additional candidate bridges with potential CIF details were identified. A review of bridge plans and pictures along with followup field investigations pinpointed bridges with CIF details that warrant up-close (i.e., arm’s length) inspections. Several uninspected bridges were identified as candidates for inspection to determine if they contain CIF details. Guidance is provided to …

New Coatings For Bridges (Over-Coat Systems), Sudhir Palle, Theodore Hopwood Ii, Bobby W. Meade

Kentucky Transportation Center Research Report

KYTC sought to identify new coatings technologies consistent with overcoating that offer enhancements in terms of ease of application and performance. KYTC contacted paint manufacturers to obtain sample coating systems for characterization by the KYTC Division of Materials and accelerated performance testing by Kentucky Transportation Center (KTC). A total of 14 coating systems from five manufacturers underwent performance testing according to ASTM D5894.

Experimental Painting Of The I-64 Riverside Parkway In Louisville, Ky, Rick Younce, Theodore Hopwood Ii, Sudhir Palle

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet conducted a large-scale zone maintenance painting operation on 13 elevated steel bridges along the I-64 Riverside Parkway in Louisville, KY in 2007. That work included abrasive blast-cleaning and painting of steel underlying open deck joints on 3.2 miles of steel structures. The painting was performed by spray application of one coat of a calcium sulfonate alkyd coating. The painting covered an area of 237,060 ft2 of steel cleaned and painted at a unit cost of $15.82/ft2.

The project incorporated a high level of containment as the existing coating possessed lead-based paints and the project was located …

Survey Of Welding Processes, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

The current KYTC “SPECIAL PROVISION NO. 4 WELDING STEEL BRIDGES” prohibits the use of welding processes other than shielded metal arc welding (SMAW) and submerged arc welding (SAW). Nationally, bridge welding is codified under ANSI/AASHTO/AWS D1.5M/D1.5:2002 Bridge Welding Code. That document allows the use of other welding processes including flux core arc welding, gas metal arc welding, electroslag welding and electrogas welding after passing qualification tests.

Both the KYTC Special Provision and the Bridge Welding Code were reviewed. Representatives from 14 state highway agencies, fabrication shops, universities and welding equipment firms were questioned regarding the wider use of the welding …

Environmentally Safe Protective Coatings For Steel Structures-New Construction And Maintenance Painting, Theodore Hopwood Ii, Christopher M. Oberst

Kentucky Transportation Center Research Report

The purpose of this study was to: 1) assist KyTC in identifying protective coatings lor structural steel that would meet current and pending environmental regulations, I and 2) to evaluate overcoating procedures that would be cost-effective and provide regulatory (OSHA and EPA) compliance.

A coatings research program was conducted that included: 1) laboratory accelerated corrosion/weathering tests, 2) field exposure tests, and 3) experimental maintenance I painting of entire bridges by overcoating. Each of those tasks was intended to address different issues. Regulations concerning volatile organic compound limits lor coating systems used in new construction were studied and recommendations provided to …

Summary Of Stress Evaluations Of Welded Steel Bridges On Coal-Haul Routes, Theodore Hopwood Ii, Keith J. Hogan, Christopher M. Oberst

Kentucky Transportation Center Research Report

Stress analyses were performed on continuous girder welded steel bridges on extended weights coal-haul routes. The tests were intended to determine whether extended weight coal trucks pose fatigue problems to those bridges. Measurements were performed by strain gaging selected bridges subject to high coal transport tonnages. Stress measurements were conducted on fatigue-prone weld details or test sites where high tensile stresses were anticipated. Test sites on the bridges were instrumented with strain gages. Strains induced by routine traffic including coal trucks were monitored for periods of one to two weeks. Unattended monitoring of the variable amplitude strain data was performed …

Stress Evaluation Of Welded Steel Bridges On Coal-Haul Routes, Theodore Hopwood Ii, Keith J. Hogan, Christopher M. Oberst

Kentucky Transportation Center Research Report

This report describes the procedure developed and being employed to determine and assess live-load stresses in structural members of welded steel bridges on extended· weight coal haul routes. Those bridges are routinely subjected to loads from coal trucks in excess of those permitted on other routes. Those elevated loads may result in high stresses in bridge members. Of principal concern are certain weld details on steel bridges that are susceptible to fatigue cracking when subject to high live-load stresses. Seventeen welded steel bridges on extended-weight coal haul routes have been identified for investigation under this study.

The study test procedure …

The Removal Of Lead-Based Paint From Steel Bridges, Theodore Hopwood Ii, Christopher M. Oberst

Kentucky Transportation Center Research Report

The purpose of this study was to assist the Department of Highways in conducting bridge-painting operations involving removal of existing lead-based paint. Pertinent state and Federal regulations affecting generation of hazardous wastes, limiting environmental pollution and protecting public and worker safety were obtained and reviewed.State highway agendas were surveyed relative to how they conducted maintenance bridge painting involving lead-based. paints and comply with applicable regulations. Information from the painting industry related to sale removal of lead-based paints was also reviewed.

Based upon the reviews of applicable regulations, operations of other state highway agencies and painting industry practices, the best demonstrated …

Survey Of Current Bridge Painting Practices And Related Literature Search, Theodore Hopwood Ii, Christopher M. Oberst

Kentucky Transportation Center Research Report

A survey on current bridge painting practices was conducted. Questionnaires were sent to all 50 state highway agencies concerning their present bridge painting practices, changes in those practices that they anticipate due to environmental regulations, and new or experimental painting practices they are investigating. Forty-three responses were received. Those are collated and presented in the appendices along with comments of the responders.

A literature search was conducted on publications related to painting of steel structures (since 1987). Forty-nine documents were identified as being relevant to the topic. Those documents are listed in bibliographic form in the appendices.

Load Indicating Washers, Theodore Hopwood Ii, Edgar E. Courtney

Kentucky Transportation Center Research Report

Kentucky Transportation Center (KTC) personnel monitored the installation of load indicating washers (LIWs) on the US 60 bridge at Catlettsburg, KY during construction. On completion of the bridge, KTC personnel performed torque measurements on a number of LIW installations. LIWs previously installed on the Thirteenth Street Bridge over the Ohio River at Ashland, KY were also inspected.

The KTC construction inspections revealed no significant problems in installing LIWs. Workers were able to use them to determine proper bolt assembly installation. They also permitted inspectors to rapidly check for proper bolt tension. As with other bolt tensioning methods, LIWs had to …

Fatigue Analysis Of The I-75 Bridge Over The Kentucky River At Clays Ferry, Theodore Hopwood Ii, Vishwas G. Oka

Kentucky Transportation Center Research Report

Fatigue analysis was performed on AASHTO category E welded connections on the southbound I 75 bridge over the Kentucky River at Clays Ferry, Kentucky. That analysis was based on the stress-range histogram data provided by Law Engineering of Louisville, Kentucky. That data were obtained from strain gages installed at 6 test locations on the downstream truss.

The fatigue analyses consisted of safe-life and fatigue-crack growth analyses. Safe-life predictions were based on AASHTO fatigue design (SN) curves. To use those curves, equivalent constant-amplitude stresses were derived from the stress histograms. Those stresses and loading frequencies were modified to reflect anticipated increases …

Calcium Nitrite As A Corrosion Inhibitor In Reinforced Concrete Bridge Decks, Theodore Hopwood Ii, David Q. Hunsucker, Edgar E. Courtney

Kentucky Transportation Center Research Report

The use of calcium nitrite es a corrosion-inhibiting admixture in reinforced concrete hes been studied on two bridges· the Kentucky 152 Bridge in Washington County and the Gose Road Bridge in Boyle County. Calcium nitrite was added to concrete used in the slabs, diaphragms and barriers of the KY 152 bridge and only in the slab of the Good Road bridge.

Construction of both structures was monitored in the fall of 1986. Placement of concrete on both bridges was satisfactory; however, problems were experienced in finishing the concrete. The finishing problems were related to: 1) concrete 'stickiness', 2) use of …

Excessive Beam Deflections On The Ky-52 Bridge Over Dix River (Boyle-Garrard County Line), Theodore Hopwood Ii, Vishwas G. Oka, David Q. Hunsucker, James H. Havens

Kentucky Transportation Center Research Report

Upon rehabilitation, beams and deck of the Ky 52 bridge over Dix River were observed to have excessive deflections. An investigation of the problem included field inspections, structural analyses, and interviews with relevant KYDOH and other personnel.

Field measurements were made of the beam deflections. Those were compared to construction field measurements and dead-load calculations.

The beam deflection problem is attributed to 1) a failure to provide for sufficient camber in the beams to accommodate for construction dead loads, and 2) pre-existing sags in the beams when placed prior to casting the deck. Part of the deck deflection problem can …

Reliability Assessment Of High-Risk Steel Bridges By Nondestructive Test Methods, Theodore Hopwood Ii, Vishwas G. Oka, Robert C. Deen

Kentucky Transportation Center Research Report

Fatigue-crack related failures of high-risk (fracture-critical) steel bridges may be prevented through application of nondestructive tests (NDT). Economical reliability assessment of those structures requires 1) application of a suitable NDT method, 2) testing of fatigue-susceptible members, and 3 ) periodic retests of those members to preclude problems with growing or previously undetected flaws.

Six conventional NDT techniques were tested in the laboratory using buttweld configured specimens having intentionally embedded cracks. Those NDT methods were 1) visual inspection, 2) magnetic-particle testing, 3) dyepenetrant testing, 4) florescent-enhanced surface testing, 5 ) eddy-current testing, and 6) ultrasonic testing. The other NDT methods provided …

Acoustic Emission Monitoring Of In-Service Bridges, Theodore Hopwood Ii, David W. Prine

Kentucky Transportation Center Research Report

An experimental acoustic emission (AE) device, the GARD Acoustic Emission Weld Monitor (AEWM), has been field tested on six bridges during this study. In addition, the device was used to test three other bridges under separate contracts from state highway agencies. The device was evaluated to determine if it could detect fatigue-crack growth on in-service steel bridges.

The AEWM employs a proprietary three-step model (filter) to reject noise-related AE activity and detect and locate defects subject to varying stress conditions. The unit uses built-in microprocessors to compare incoming data to the model. If defect-related AE activity is detected, the AEWM …

Demonstration And Preliminary Evaluation Of The Acoustic Emission Weld Monitor, Theodore Hopwood Ii, Robert C. Deen

Kentucky Transportation Center Research Report

This report describes the demonstration and preliminary evaluation of the microprocessor-based acoustic emission weld monitor (AEWM) developed for the Federal Highway Administration by GARD Inc. of Niles, IL. The equipment was tested successfully on butt welds in several fabrication shops by the Kentucky Transportation Research Program (KTRP). Some problems were encountered in monitoring fillet welds.

The AEWM was demonstrated to personnel from 20 state agencies representing FHWA Regions 1, 3, 4, and 5. The demonstrations were performed at three different fabrication shops in Pennsylvania, Georgia, and Wisconsin.

A preliminary evaluation of the AEWM is included. Also, the summary of a …

Inspection, Prevention, And Remedy Of Suspension Bridge Cable Corrosion Problems, Theodore Hopwood Ii, James H. Havens

Kentucky Transportation Center Research Report

This report discusses methods for visually inspecting cable suspension bridges for corrosion damage. The report discusses how to plan and perform such work, including the locations on cables where corrosion damage is likely to be detected. The report also provides recommendations for assessing the condition of suspension bridge wire. Recommendations also are included for remedial cable repair work should corrosion damage be detected.

Introduction To Cable Suspension Bridges, Theodore Hopwood Ii, James H. Havens

Kentucky Transportation Center Research Report

This report is an overview of suspension bridges. A historical perspective of bridge construction design and materials is included, focusing on bridges of interest to the Kentucky Transportation Cabinet. The report is intended to provide background information on suspension bridges to those not well acquainted with the structures.

Corrosion Of Cable Suspension Bridges, Theodore Hopwood Ii, James H. Havens

Kentucky Transportation Center Research Report

This report discusses corrosion problems encountered on the cables of suspension bridges. A historical review is given of past cable suspension bridge corrosion and related laboratory work.

Findings of inspections of suspension bridges at Maysville, KY, Covington, KY, and Portsmouth, OH, are discussed. Recommendations are presented.

Acoustic Emission Monitoring Of Weldments, Theodore Hopwood Ii, James H. Havens

Kentucky Transportation Center Research Report

Weld tests were performed on low-carbon and high-strength, low-alloy steel weldments. The weldments were monitored with an acoustic emission detector during both the 'in-process' and the 'in-cooling' phases of the welding operation. Artificial defects were induced in several of the welds to promote cracking. Some high-strength weldments were designed to produce welds subject to high restraint.

Nondestructive and destructive evaluation of the completed weldments revealed that high acoustic emission activity 'in-cooling' could be correlated with embedded defects and cold-cracking. Copious emission activity was also detected from unflawed weldments. Acoustic emissions were detected in high-strength steel weldments for periods up to …