Experimental Maintenance Painting by Overcoating on the I-64, I-71 and KY-22 Bridges

In 1995, KYTC let three experimental maintenance-painting projects. Two of those projects involved the painting of multiple bridges along interstate routes. Those projects encompassed four mainline steel bridges on 1-64 in Franklin County, 16 mainline and overpass steel bridges along 1-71 in six counties, and 660 steel rockers on 36 concrete bridges on 1-71. The steel projects included mainline deck girder structures on the 1-64 project and a mix of mainline and overpass deck girder structures and steel bearings on concrete bridges in the 1-71 project. The third project entailed the painting of a single steel truss bridge, KY -22 over the Licking River at Falmouth, KY. All of those bridges had existing lead based paint. The condition of the existing paint varied from extremely poor on the KY-22 bridge to fair-to-good on the 1-64 and 1-71 structures. Each of the projects was awarded to a different contractor. These projects incorporated the then current KYTC practice of non-invasive painting. Surface preparation procedures were specified that were intended to avoid generation of hazardous wastes. The resulting specifications did not incorporate mechanical surface preparation procedures. However, to provide more efficient cleaning of the existing paint, the washing pressure on the three projects was increased (1,500 psi for the 1-71 project, 2,500-psi for 1-64 project and 3,500 psi for KY-22 project) over previous experimental projects. Polyurethane paints were employed on all three projects. This was due to the good performance achieved by that type of coating in previous experimental projects. The paint systems used on the 1-64 and 1-71 projects were compositional specifications provided by KYTC. The paint system for the 1-64 project employed both spot and full prime coats of aluminum-pigmented moisture cure polyurethane followed by a two-component aliphatic acrylic high-gloss polyurethane topcoat. The paint system for the 1-71 project used a spot prime coat of an aluminum- and micaceous iron oxide (MIO)-pigmented moisture cure polyurethane and a two-component aliphatic acrylic high-gloss polyurethane topcoat. Different paint manufacturers supplied paint for the 1-64 and 1-71 projects. A proprietary polyurethane coating system from a third manufacturer was used for the KY-22 project. The spot and full prime coats consisted of aluminum-pigmented moisture cure polyurethane paint followed by a two-component aliphatic acrylic high-gloss polyurethane topcoat. On all three projects, the primer was to be applied by brushing. The contractor on the 1-64 bridges was allowed to apply the intermediate coat by rolling. The contractors could use brushing, rolling or spraying to apply the topcoats. The contractor on the 1-64 project sprayed on the topcoat. The contractor on the 1-71 project brushed and rolled topcoat on the overpass bridges and sprayed topcoat on the mainline ones. The contractor on the KY-22 Bridge elected to use paint mitts to apply all three coats of paint due to the close proximity of houses to the structure

Acoustic Emission Monitoring of In-Service Bridges

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 will notify the operator and locate the defect in relation to AE sensors placed on the test specimen. The device rejects high background noise rates typical of bridges and detects and locates AE activity from known defects such as cracks and subsurface flaws. The AEWM functioned properly in every field test situation to which it was applied. The device has demonstrated capability to perform AE tests on in-service bridges. It may be used to detect hidden defects or to assist in making repair decisions concerning detected discontinuities. The AEWM and AE testing have the potential for low-cost inspection of critical bridge members

Manual on Bridge/Culvert Maintenance

The basic objective of this course is to provide background (introductory) technical information that will aid the manager of bridge/culvert installations. In most instances, information presented may not be sufficiently complete for the student to perform the required work. However, the intent is more to familiarize than to instruct In many instances, professional engineering and experienced labor are necessary to ensure successful completion of tasks. Once the local official responsible for bridges and culverts has completed this workshop, he should have a basic understanding of the most common bridges/culverts encountered in counties and municipalities, the major components of common bridge/culvert types and their functions, common bridge/culvert materials, material deterioration in bridge/culvert service, various bridge/culvert maintenance requirements, specific bridge/culvert rehabilitation techniques, and decision-making procedures for bridge/culvert managemen

Improved Structural Monitoring with Acoustic Emission Pattern Recognition

A unique acoustic emission monitoring system originally developed for inprocess weld monitoring has been used to monitor fatigue crack growth in a highway bridge during normal traffic loading. The system was able to clearly and reliably detect the presence of fatigue cracks that were adjacent to a row of bolts. The results of the brief experiment show that the signal processing used in this AE system may allow drastic improvements in the ability of acoustic emission to reliably detect propagating bridge flaws under adverse conditions

An Analysis of Wastewater Generated During Water Jetting Tests on the I-65 John F. Kennedy Bridge at Louisville

High pressure water jetting was evaluated as a surface preparation tool for bridge maintenance painting. The tests were conducted on the John F. Kennedy Bridge, which has lead containing existing paint system. The primary concerns were the surface preparation and the lead levels of the wastewater. Test areas were washed at 10,000 psi, 15,000 psi, and 20,000 psi and wastewater was collected for analysis. Lead tests were conducted on unfiltered wastewater and wastewater filtered through a variety of filter fabrics. High-pressure water jetting produces and excellent surface for painting but, on bridges with existing lead paint, the wastewater lead levels are too high for conventional KyDOH filtering requirements

Experimental Rapid Renewal Project (Bridge Construction)

The objectives of this study were to develop specifications and contract language and to monitor the implementation them to effectively use rapid reconstruction and extended service life concepts in new bridge construction. Through the use of A + B bidding, a duplex protective coating system using Hot Dipped Galvanizing (HDG) and paint, and preservation techniques such as concrete sealers and stains the Kentucky Transportation Cabinet attained those goals

Leading and Managing the 21st Century Research University: Creating, Implementing, and Sustaining Strategic Change

Universities are competing in an environment in which only the most adaptable to sustainable change will prosper. In order to evolve in this challenging time, universities must embrace strategies for transformational change. This paper reviews two case studies that illustrate the universal applicability of theories of Change Science for achieving sustainable change in stressful times of prosperity and austerity. Understanding the phases of the Change Process that include Creating Vision, Implementing Vision, and Sustaining Vision can promote sustainable change directly related to the culture and mission of the institution

Specially Constructed Bridges: Activities for Fiscal Year 1983

The field performance of bridge features including masonry coatings, galvanized steel, weathering steel, conventional deck reinforcing steel, and epoxy-coated reinforcing steel were examined either visually or nondestructively on various pre-selected bridges throughout Kentucky. Additionally, a nationwide survey of state highway authorities was conducted on the application and service performance of stay-in-place forms. All of the bridge features inspected appeared to be performing satisfactorily, except for the masonry coating failure on the I-471 twin bridges over the Ohio River at Newport. Results of the stay-in-place form survey support their application as a cost-saving feature

Improved Bridge Joint Materials and Design Details

Expansion joints accommodate bridge movements that result from factors such as thermal expansion and contraction, concrete shrinkage, creep effects, live loading, settlement of the foundation and substructure, and environmental stressors. Expansion joints fall into two categories — open joints and closed joints. Open joints contain gaps that facilitate the passage of water and debris runoff through bridge joints. Flexible or stiff troughs are generally installed beneath open joints to direct runoff away from bridge elements. Closed joints produce a watertight seal that inhibits water, debris, and deicing materials from passing through bridge joints and remaining in contact with underlying bridge components. This study investigated materials and design strategies to improve the performance of both open and closed joints. Wanting to improve the durability of compression and strip seals, which degrade over time or become detached from bridge decks, Kentucky Transportation Center (KTC) researchers approached several seal manufacturers about developing new seals reinforced with puncture-resistant fibers such as Aramid. Ultimately, researchers were unable to reach an agreement with any manufacturer, as it appears they have little interest in developing better-performing conventional joint types, preferring instead to focus on producing new proprietary joint types. As the Kentucky Transportation Cabinet (KYTC) increases its use of proprietary joints, it should implement a rigorous monitoring program to track their performance. With respect to open joints, KTC investigated the use of self-purging troughs. First implemented by the Kansas Department of Transportation, they leverage the power of air flow and vibrations produced by traffic to improve the routing of water and debris through troughs and away from underlying bridge elements. Conventional troughs receive infrequent maintenance and can become clogged with debris. Self-purging troughs eliminate this problem, which can potentially help extend the service lives of bridges on which they are installed. KYTC will benefit from experimenting more widely with self-purging troughs