Sudhir Palle - Academia.edu (original) (raw)
Papers by Sudhir Palle
The objectives of this study were to develop specifications and contract language and to monitor ... more 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.
![Research paper thumbnail of Assessment and Modeling of Stream Mitigation Procedures [2003]](https://attachments.academia-assets.com/101105252/thumbnails/1.jpg)
](As population increases, so does the need to improve and augment the road network. Construction o... more As population increases, so does the need to improve and augment the road network. Construction of new roadways or modification of existing roads often requires diversion or modification of streams. If a stream is disturbed, government regulations require mitigation or compensatory replacement of the affected area in a similar environment. Stream mitigation is of particular importance in Kentucky, as Kentucky ranks second in the United States for having the most miles of waterways. Consequently, stream mitigation has become a significant factor in roadway construction costs. To date, no studies have been made to assess the execution of the mitigation plans or to determine the performance of mitigation projects. In a move to rectify this situation, the Kentucky Transportation Cabinet requested this study.
The Kentucky Transportation Cabinet conducted a large-scale zone maintenance painting operation o... more 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 in a densely populated area. The project was successfully completed in 4 months. Follow-on inspections conducted at 2 and 14 months respectively indicated that almost all of the zone painting was in good condition and performing satisfactorily.
Kentucky's bridges continue to age and experience distress. The intrusion of chlorides into c... more Kentucky's bridges continue to age and experience distress. The intrusion of chlorides into concrete remains the primary mechanism for deterioration. It leads to reinforcing steel corrosion that damages the adjoining concrete structure. This study found problematic chloride concentrations in Kentucky concrete bridge elements (decks, pier caps, abutments). Chloride levels have been found at concentrations sufficient to initiate reinforcing steel corrosion. In some cases, chloride concentrations were sufficient to cause accelerated corrosion and produce major section loss of reinforcing steel. Advanced stages of corrosion such as these typically require costly repairs and maintenance to extend the service life of bridges. Field inspections and laboratory analyses conducted during this study verified the ongoing problem of concrete deterioration across bridges within Kentucky's transportation network.
The Kentucky Transportation Cabinet (KYTC) has both open and closed bridge expansion joints and a... more The Kentucky Transportation Cabinet (KYTC) has both open and closed bridge expansion joints and associated details that are problematic. Several state highway agencies (SHA) have joints that they believe are superior performers to other types and have prepared guidance documents for their use. A literature search indicated that several previous research studies, including national surveys, addressing SHA joint practices have been conducted over the past 10 years. For up-to-date information, a new set of surveys were developed and distributed to all the SHAs by email through the AASHTO Subcommittee on Maintenance - Bridge Technical Working Group chairman in June 2010. There were two sets of surveys: 1) design and construction, and 2) maintenance, that were submitted to two separate entities within each SHA.
The US 231 Natcher Bridge was opened in 2002. By 2006 cracking was observed in the plastic piping... more The US 231 Natcher Bridge was opened in 2002. By 2006 cracking was observed in the plastic piping that protected the stay cable strands from the environment at both the deck and tower anchorages. Over time the extent of cracking increased and an investigation was initiated to assess the types of deterioration impacting the cables, their causes and their impacts on the integrity of the stay cables. From 2012-2015, a series of in-depth field inspections were performed using visual and nondestructive testing. Most of this work focused on the piping at the deck anchorages. The inspections disclosed voids in cable grouting, bad welds in the plastic piping and deterioration of the co-extruded outer layer of the piping. Water was detected during inspections of the cable ends at the anchor blocks along with minimal corrosion of the strands and anchorages. The water and samples of the plastic piping were evaluated and found to be problematic. No direct indications of cable corrosion damage w...
Preventing or mitigating the corrosion of reinforcing steel in bridge decks is a major challenge ... more Preventing or mitigating the corrosion of reinforcing steel in bridge decks is a major challenge for state transportation agencies. With agency budgets stretched thinner every year, they must implement strategies to extend the service lives of bridges and other critical structures. As such, it is imperative for them to adopt cost effective materials and maintenance practices to delay the onset of bridge corrosion. To assist the Kentucky Transportation Cabinet (KYTC) in its efforts to improve the condition of its bridges as well as its construction and maintenance practices, researchers at the Kentucky Transportation Center (KTC) investigated the use and performance of different reinforcing materials, supplementary cementitious materials, and concrete sealers. This document extensively reviews field and laboratory studies of these materials and draws general conclusions about their effectiveness. A survey administered to transportation agencies around the United States revealed that corrosion prevention and mitigation practices vary widely, but that the use of multiple corrosion-inhibition systems is growing. Based on our literature review and analysis of practices used by other state transportation agencies, we recommend the use of multiple corrosioninhibition methods to defend against bridge corrosion. For the construction of new reinforced concrete structures, a multiple approach to corrosion resistance could prove highly beneficial and offer a cost-effective strategy to prolong the service lives of bridges. Recommended actions are proposed for KYTC, which are geared toward strengthening its bridge construction and maintenance program.
Transportation Center is committed to a policy of providing equal opportunities for al persons in... more Transportation Center is committed to a policy of providing equal opportunities for al persons in recruitment, appointment, promotion, payment, training, and other employment and education practices without regard for economic, or social status and will not discriminate on the basis of race, color, ethnic origin, national origin, creed, religion, political belief, sex, sexual orientation, marital status or age.
We provide services to the transportation community through research, technology transfer and edu... more We provide services to the transportation community through research, technology transfer and education. We create and participate in partnerships to promote safe and effective transportation systems.
Bridge maintenance painting employs solvent-based coatings that generate volatile organic compoun... more Bridge maintenance painting employs solvent-based coatings that generate volatile organic compounds (VOCs) that contribute to air-quality problems. Methods for capturing VOCs during normal Kentucky Transportation Cabinet (KYTC) maintenance painting operations were investigated. One method, activated carbon adsorption, is adaptable to KYTC operations. Related factors including area of bridge, coating systems, containment volumes and VOC out gassing rates were reviewed. A commercial source of activated carbon adsorption equipment was identified and issues related to employing that technology for bridge painting were identified.
Transportation Center is committed to a policy of providing equal opportunities for al persons in... more Transportation Center is committed to a policy of providing equal opportunities for al persons in recruitment, appointment, promotion, payment, training, and other employment and education practices without regard for economic, or social status and will not discriminate on the basis of race, color, ethnic origin, national origin, creed, religion, political belief, sex, sexual orientation, marital status or age.
Three defective ASTM A 514 steel splice plates were discovered on the I-275 Combs-Hehl twin bridg... more Three defective ASTM A 514 steel splice plates were discovered on the I-275 Combs-Hehl twin bridges over the Ohio River. A follow-up in-depth field inspection of 1,356 A 514 steel plates on the bridges revealed 14 additional defective gusset and splice plates. The A 514 steel was improperly heat-treated resulting in a brittle crack-prone microstructure. Ultrasonic and impact hardness tests were used to identify the defective steel. Subsequently, the defective steel plates were either removed or lapped with additional steel plates.
Kinniconnick Creek (MP 27.124) in Lewis Co. KTC researchers were involved in those projects at th... more Kinniconnick Creek (MP 27.124) in Lewis Co. KTC researchers were involved in those projects at the request of KYTC personnel with an understanding that no reporting would be done for these projects. The above listed bridges were let and finished by the end of fiscal year 1996 before KHIT 31 was approved.
Optically active pigments (OAPs) fluoresce under light exposure with wavelengths (<200 to 400 ... more Optically active pigments (OAPs) fluoresce under light exposure with wavelengths (<200 to 400 nm) producing emissions in the visible spectra (380 to 740 nm). They are used as paint pigments to aid visual inspection of applied coatings for defects such as pin-holing and incomplete coverage. OAP coatings are widely used in various industries outside of bridge maintenance painting. This study addressed the laboratory evaluation and field trial of an OAP coating for Kentucky Transportation Cabinet (KYTC) bridges. OAP coatings were evaluated for inspectability and accelerated weathering performance in a laboratory test program. After successful laboratory performance, OAP coatings were specified for a KYTC bridge painting project incorporating two deck-girder bridges. One bridge was coated with an OAP zinc urethane primer/non-OAP epoxy mid-coat/OAP urethane top-coat system. The second bridge was coated with a non-OAP zinc urethane primer/OAP epoxy mid-coat/non-OAP urethane top-coat. F...
State transportation agencies use cost-effective preventive maintenance (PM) programs to preserve... more State transportation agencies use cost-effective preventive maintenance (PM) programs to preserve existing roadway systems, slow down their deterioration, and improve their functional condition. Currently, KYTC's bridge inventory includes approximately 10,000 structures, and by 2018, most of these structures will have been in use for at least 50 years. Because there is insufficient funding available to pursue a large-scale bridge replacement program, it is critical for the Cabinet to prolong the lives of its bridges by using economical strategies. This report provides guidance that the Kentucky Transportation Cabinet (KYTC) can use to develop and implement a statewide bridge PM program. Drawing from previous Kentucky Transportation Center (KTC) research studies and interviews with other state transportation agencies, the report describes eight bridge PM activities that KYTC can leverage to maintain and enhance its current portfolio of bridges. It provides technical overviews of each activity. These activities include: 1) resealing and repairing joints; 2) cleaning and sealing bearings; 3) bridge washing; 4) sealing decks; 5) spot painting; 6) patching bridge decks; 7) cleaning and painting pier caps and abutments; and 8) scour, drift, sediment, and bank stabilization. KYTC would benefit from incorporating PM activities into a holistic bridge preservation program to extend the service lives of its bridges.
This study evaluates the construction and performance of the Kentucky Department of Transportatio... more This study evaluates the construction and performance of the Kentucky Department of Transportation stream disturbance mitigation projects. The initial study tasks were a literature search, a review of stream performance models, a review of Kentucky's and other agencies' regulations pertaining to stream mitigation, identification of representative stream mitigation projects, and evaluation of those stream mitigation sites. The results of this study will be a tool for evaluating stream mitigation projects after they are constructed.
Kentucky Transportation Cabinet (KYTC) sought to identify new coatings technologies consistent wi... more Kentucky Transportation Cabinet (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 American Society for Testing and Materials (ASTM) D5894.
Cleaning (washing) operations of existing leaded paints on bridges were studied to determine the ... more Cleaning (washing) operations of existing leaded paints on bridges were studied to determine the level of lead contamination in the resulting wastewater. Twelve experimental overcoating projects were let on bridges with various types of existing paint in varying states of deterioration. The projects employed different washing pressures ranging from 2500 psi to 10,000 psi and various wash nozzles (fan and 0 deg spinner tips). Kentucky Transportation Cabinet standard filtration was used on 10 projects and 2 projects used an experimental filtration unit having a sand filter and two types of chemical filter media. Prior to painting, the existing paint was analyzed for thickness, adhesion, and lead content. Wastewater generated during maintenance painting operations (potable, unfiltered and filtered) was sampled and analyzed for lead content (total and dissolved), total suspended solids and pH. No clear correlations were obtained between lead in the wastewater, wash pressures, nozzle typ...
The Riverside Parkway comprises some 3.2 miles of elevated steel (plate-girder) in downtown Louis... more The Riverside Parkway comprises some 3.2 miles of elevated steel (plate-girder) in downtown Louisville having approximately 24,054 tons of steel. The structures had existing coatings that contained lead. The project posed significant operational and public safety constraints due to close proximity of the structures with residences and businesses along the entire route. In 1996, the Kentucky Transportation Cabinet Paint Team developed experimental specifications to re-paint the Parkway by overcoating. Surface preparation procedures included 3,000-psi pressure washing and power-tool cleaning. Containment enclosures were employed throughout the project and hazardous wastes were collected and disposed of. The Parkway spans were painted with a brushed-on spot coat and full brushed-on intermediate coat of aluminum-pigmented moisture cure polyurethane primer and rolled or spray-applied topcoat of high-gloss acrylic polyurethane. The project was let at a cost of about $1.20/sq ft. The paint...
The objectives of this study were to develop specifications and contract language and to monitor ... more 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.
As population increases, so does the need to improve and augment the road network. Construction o... more As population increases, so does the need to improve and augment the road network. Construction of new roadways or modification of existing roads often requires diversion or modification of streams. If a stream is disturbed, government regulations require mitigation or compensatory replacement of the affected area in a similar environment. Stream mitigation is of particular importance in Kentucky, as Kentucky ranks second in the United States for having the most miles of waterways. Consequently, stream mitigation has become a significant factor in roadway construction costs. To date, no studies have been made to assess the execution of the mitigation plans or to determine the performance of mitigation projects. In a move to rectify this situation, the Kentucky Transportation Cabinet requested this study.
The Kentucky Transportation Cabinet conducted a large-scale zone maintenance painting operation o... more 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 in a densely populated area. The project was successfully completed in 4 months. Follow-on inspections conducted at 2 and 14 months respectively indicated that almost all of the zone painting was in good condition and performing satisfactorily.
Kentucky's bridges continue to age and experience distress. The intrusion of chlorides into c... more Kentucky's bridges continue to age and experience distress. The intrusion of chlorides into concrete remains the primary mechanism for deterioration. It leads to reinforcing steel corrosion that damages the adjoining concrete structure. This study found problematic chloride concentrations in Kentucky concrete bridge elements (decks, pier caps, abutments). Chloride levels have been found at concentrations sufficient to initiate reinforcing steel corrosion. In some cases, chloride concentrations were sufficient to cause accelerated corrosion and produce major section loss of reinforcing steel. Advanced stages of corrosion such as these typically require costly repairs and maintenance to extend the service life of bridges. Field inspections and laboratory analyses conducted during this study verified the ongoing problem of concrete deterioration across bridges within Kentucky's transportation network.
The Kentucky Transportation Cabinet (KYTC) has both open and closed bridge expansion joints and a... more The Kentucky Transportation Cabinet (KYTC) has both open and closed bridge expansion joints and associated details that are problematic. Several state highway agencies (SHA) have joints that they believe are superior performers to other types and have prepared guidance documents for their use. A literature search indicated that several previous research studies, including national surveys, addressing SHA joint practices have been conducted over the past 10 years. For up-to-date information, a new set of surveys were developed and distributed to all the SHAs by email through the AASHTO Subcommittee on Maintenance - Bridge Technical Working Group chairman in June 2010. There were two sets of surveys: 1) design and construction, and 2) maintenance, that were submitted to two separate entities within each SHA.
The US 231 Natcher Bridge was opened in 2002. By 2006 cracking was observed in the plastic piping... more The US 231 Natcher Bridge was opened in 2002. By 2006 cracking was observed in the plastic piping that protected the stay cable strands from the environment at both the deck and tower anchorages. Over time the extent of cracking increased and an investigation was initiated to assess the types of deterioration impacting the cables, their causes and their impacts on the integrity of the stay cables. From 2012-2015, a series of in-depth field inspections were performed using visual and nondestructive testing. Most of this work focused on the piping at the deck anchorages. The inspections disclosed voids in cable grouting, bad welds in the plastic piping and deterioration of the co-extruded outer layer of the piping. Water was detected during inspections of the cable ends at the anchor blocks along with minimal corrosion of the strands and anchorages. The water and samples of the plastic piping were evaluated and found to be problematic. No direct indications of cable corrosion damage w...
Preventing or mitigating the corrosion of reinforcing steel in bridge decks is a major challenge ... more Preventing or mitigating the corrosion of reinforcing steel in bridge decks is a major challenge for state transportation agencies. With agency budgets stretched thinner every year, they must implement strategies to extend the service lives of bridges and other critical structures. As such, it is imperative for them to adopt cost effective materials and maintenance practices to delay the onset of bridge corrosion. To assist the Kentucky Transportation Cabinet (KYTC) in its efforts to improve the condition of its bridges as well as its construction and maintenance practices, researchers at the Kentucky Transportation Center (KTC) investigated the use and performance of different reinforcing materials, supplementary cementitious materials, and concrete sealers. This document extensively reviews field and laboratory studies of these materials and draws general conclusions about their effectiveness. A survey administered to transportation agencies around the United States revealed that corrosion prevention and mitigation practices vary widely, but that the use of multiple corrosion-inhibition systems is growing. Based on our literature review and analysis of practices used by other state transportation agencies, we recommend the use of multiple corrosioninhibition methods to defend against bridge corrosion. For the construction of new reinforced concrete structures, a multiple approach to corrosion resistance could prove highly beneficial and offer a cost-effective strategy to prolong the service lives of bridges. Recommended actions are proposed for KYTC, which are geared toward strengthening its bridge construction and maintenance program.
Transportation Center is committed to a policy of providing equal opportunities for al persons in... more Transportation Center is committed to a policy of providing equal opportunities for al persons in recruitment, appointment, promotion, payment, training, and other employment and education practices without regard for economic, or social status and will not discriminate on the basis of race, color, ethnic origin, national origin, creed, religion, political belief, sex, sexual orientation, marital status or age.
We provide services to the transportation community through research, technology transfer and edu... more We provide services to the transportation community through research, technology transfer and education. We create and participate in partnerships to promote safe and effective transportation systems.
Bridge maintenance painting employs solvent-based coatings that generate volatile organic compoun... more Bridge maintenance painting employs solvent-based coatings that generate volatile organic compounds (VOCs) that contribute to air-quality problems. Methods for capturing VOCs during normal Kentucky Transportation Cabinet (KYTC) maintenance painting operations were investigated. One method, activated carbon adsorption, is adaptable to KYTC operations. Related factors including area of bridge, coating systems, containment volumes and VOC out gassing rates were reviewed. A commercial source of activated carbon adsorption equipment was identified and issues related to employing that technology for bridge painting were identified.
Transportation Center is committed to a policy of providing equal opportunities for al persons in... more Transportation Center is committed to a policy of providing equal opportunities for al persons in recruitment, appointment, promotion, payment, training, and other employment and education practices without regard for economic, or social status and will not discriminate on the basis of race, color, ethnic origin, national origin, creed, religion, political belief, sex, sexual orientation, marital status or age.
Three defective ASTM A 514 steel splice plates were discovered on the I-275 Combs-Hehl twin bridg... more Three defective ASTM A 514 steel splice plates were discovered on the I-275 Combs-Hehl twin bridges over the Ohio River. A follow-up in-depth field inspection of 1,356 A 514 steel plates on the bridges revealed 14 additional defective gusset and splice plates. The A 514 steel was improperly heat-treated resulting in a brittle crack-prone microstructure. Ultrasonic and impact hardness tests were used to identify the defective steel. Subsequently, the defective steel plates were either removed or lapped with additional steel plates.
Kinniconnick Creek (MP 27.124) in Lewis Co. KTC researchers were involved in those projects at th... more Kinniconnick Creek (MP 27.124) in Lewis Co. KTC researchers were involved in those projects at the request of KYTC personnel with an understanding that no reporting would be done for these projects. The above listed bridges were let and finished by the end of fiscal year 1996 before KHIT 31 was approved.
Optically active pigments (OAPs) fluoresce under light exposure with wavelengths (<200 to 400 ... more Optically active pigments (OAPs) fluoresce under light exposure with wavelengths (<200 to 400 nm) producing emissions in the visible spectra (380 to 740 nm). They are used as paint pigments to aid visual inspection of applied coatings for defects such as pin-holing and incomplete coverage. OAP coatings are widely used in various industries outside of bridge maintenance painting. This study addressed the laboratory evaluation and field trial of an OAP coating for Kentucky Transportation Cabinet (KYTC) bridges. OAP coatings were evaluated for inspectability and accelerated weathering performance in a laboratory test program. After successful laboratory performance, OAP coatings were specified for a KYTC bridge painting project incorporating two deck-girder bridges. One bridge was coated with an OAP zinc urethane primer/non-OAP epoxy mid-coat/OAP urethane top-coat system. The second bridge was coated with a non-OAP zinc urethane primer/OAP epoxy mid-coat/non-OAP urethane top-coat. F...
State transportation agencies use cost-effective preventive maintenance (PM) programs to preserve... more State transportation agencies use cost-effective preventive maintenance (PM) programs to preserve existing roadway systems, slow down their deterioration, and improve their functional condition. Currently, KYTC's bridge inventory includes approximately 10,000 structures, and by 2018, most of these structures will have been in use for at least 50 years. Because there is insufficient funding available to pursue a large-scale bridge replacement program, it is critical for the Cabinet to prolong the lives of its bridges by using economical strategies. This report provides guidance that the Kentucky Transportation Cabinet (KYTC) can use to develop and implement a statewide bridge PM program. Drawing from previous Kentucky Transportation Center (KTC) research studies and interviews with other state transportation agencies, the report describes eight bridge PM activities that KYTC can leverage to maintain and enhance its current portfolio of bridges. It provides technical overviews of each activity. These activities include: 1) resealing and repairing joints; 2) cleaning and sealing bearings; 3) bridge washing; 4) sealing decks; 5) spot painting; 6) patching bridge decks; 7) cleaning and painting pier caps and abutments; and 8) scour, drift, sediment, and bank stabilization. KYTC would benefit from incorporating PM activities into a holistic bridge preservation program to extend the service lives of its bridges.
This study evaluates the construction and performance of the Kentucky Department of Transportatio... more This study evaluates the construction and performance of the Kentucky Department of Transportation stream disturbance mitigation projects. The initial study tasks were a literature search, a review of stream performance models, a review of Kentucky's and other agencies' regulations pertaining to stream mitigation, identification of representative stream mitigation projects, and evaluation of those stream mitigation sites. The results of this study will be a tool for evaluating stream mitigation projects after they are constructed.
Kentucky Transportation Cabinet (KYTC) sought to identify new coatings technologies consistent wi... more Kentucky Transportation Cabinet (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 American Society for Testing and Materials (ASTM) D5894.
Cleaning (washing) operations of existing leaded paints on bridges were studied to determine the ... more Cleaning (washing) operations of existing leaded paints on bridges were studied to determine the level of lead contamination in the resulting wastewater. Twelve experimental overcoating projects were let on bridges with various types of existing paint in varying states of deterioration. The projects employed different washing pressures ranging from 2500 psi to 10,000 psi and various wash nozzles (fan and 0 deg spinner tips). Kentucky Transportation Cabinet standard filtration was used on 10 projects and 2 projects used an experimental filtration unit having a sand filter and two types of chemical filter media. Prior to painting, the existing paint was analyzed for thickness, adhesion, and lead content. Wastewater generated during maintenance painting operations (potable, unfiltered and filtered) was sampled and analyzed for lead content (total and dissolved), total suspended solids and pH. No clear correlations were obtained between lead in the wastewater, wash pressures, nozzle typ...
The Riverside Parkway comprises some 3.2 miles of elevated steel (plate-girder) in downtown Louis... more The Riverside Parkway comprises some 3.2 miles of elevated steel (plate-girder) in downtown Louisville having approximately 24,054 tons of steel. The structures had existing coatings that contained lead. The project posed significant operational and public safety constraints due to close proximity of the structures with residences and businesses along the entire route. In 1996, the Kentucky Transportation Cabinet Paint Team developed experimental specifications to re-paint the Parkway by overcoating. Surface preparation procedures included 3,000-psi pressure washing and power-tool cleaning. Containment enclosures were employed throughout the project and hazardous wastes were collected and disposed of. The Parkway spans were painted with a brushed-on spot coat and full brushed-on intermediate coat of aluminum-pigmented moisture cure polyurethane primer and rolled or spray-applied topcoat of high-gloss acrylic polyurethane. The project was let at a cost of about $1.20/sq ft. The paint...