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76 APPENDIX C Responses to Questionnaire

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Cochrane Africatown Questionnaire Results Alabama Survey performed in 2004 Cochrane Africatown Q4-11: Type of cable sheathing used? no State/Province: Alabama HDPE with PVF Tedlar tape Q4-20: Do cables have other dampers (other than viscous or neoprene rings) to control Agency: Alabama DOT Q4-12: Have rainwind-induced cable vibrations? vibrations been observed on this bridge? Respondent: Fred Conway no yes Span Length: 780 ft Q4-21: Has cracking of the cable sheathing or Q4-13: Have MTE corrosion problems been Year Built: 1991 sheathing connections been noted? noted? Q4-4: Type of main tension element (MTE)? no no seven-wire steel strand Q4-22: Has cracking or misalignment of the Q4-14: Do cables have neoprene rings near the guide pipes been noted? Q4-5: Coating/treatment on main tension top and bottom anchorages? element within free length of cable? yes--misalignment yes bare Q4-23: If there is protective tape wrapped Q4-15: If there are neoprene rings on the around the cable sheathing; have there been 77 Q4-6: Are the coatings/treatments on main cables; have there been any reports of reports of deterioration of the tape? tension element discontinued or removed movements of the rings out of their positions? within the anchorage zone? yes--minor damage yes--due to loosening of retainers, and yes-- N/A due to shearing off of retainers Q4-24: Have any problems associated with neoprene boots been noted? Q4-7: Type of grout used? Q4-16: Has moisture been found in any of the internal components of stay cables such as the yes cementwater admixtures bottom anchorage areas? Q4-25: Types of non-destructive tests that any Q4-8: Are filler materials used in the yes of the cables on this bridge have been subjected anchorage zone? to? Q4-17: Has fatigue of MTE or other yes, other components of stay cables been observed? ultrasonic and vibration-based force Q4-9: Type of anchorage? measurements no conical socket with wedges Q4-26: Types of sensor-based, long-term Q4-18: Do the cables have viscous dampers monitoring performed on the cables? Q4-10: Do cables go over "saddles" on the installed at deck or tower levels? pylons? vibration monitoring yes--retrofitted to correct vibrations no Q4-27: Have the cables on this bridge (or any Q4-19: Do the cables have cross cables of their components) been repaired? installed between them?

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Cochrane Africatown Questionnaire Results Alabama Survey performed in 2004 yes--some neoprene boots were replaced Several non-destructive tests were run after an Q11: What do you see as the single most extreme oscillation event. Practically all the important problem in stay cable maintenance? Q4-28: Has the sheathing been partially above were performed to determine if there removed on any of the cables to examine Stay anchors. (Access and rainwind-induced was any loss of force in the stays. Geometric, condition of grout (if applicable) and/or the oscillation.) physical and visual tests were performed. The MTE? only discoveries were deficiencies in the Q12: Please comment on any other methods for yes--thorough inspection performed. Selected original construction which were corrected inspections, testing, monitoring, and repair of cables were opened up where voids in grout stay cable (including conventional methods) Q7: Please comment on the effectiveness of were detected that you have found beneficial and are not any cable vibration control measures that you listed above. Q4-29: Can the strands or cables be replaced if may be familiar with. Examples include needed? installation of cross cables, viscous dampers, no answer neoprene rings, etc. yes--individual strands cannot be replaced Additional comments? but an entire stay can be replaced We realigned stay pipes and replaced neoprene rings and keeper rings. Also Q4-30: Do you have an inspection and external hydraulic dampers were installed on maintenance manual for this bridge? the longer stays 78 yes Q8: Please comment on the effectiveness of Q5: Based on your experience and in general, any sensor-based, long-term monitoring do you believe that the current inspection, systems for stay cables that you may be testing, monitoring, and repair methods familiar with. Examples include acoustic available to you for stay cables are effective monitoring, vibration monitoring, force and adequate? measurements, strain measurements, etc. yes Check with A.G. Lichtenstein Q6: Please comment on the effectiveness of Q9: What would you recommend that the cable any non-destructive test methods for suppliers incorporate into their systems to make inspections of stay cables that you may be cables more accessible and inspectable? familiar with. These methods include (but are Provide access on inside and outside of tower not limited to) ultrasonic testing, magnetic anchorage. inspections, laser-based force measurements, X-ray imaging, etc. If possible, please Q10: Do you believe that an up-to-date comment on issues such as practicality, cost, resource such as a national database of duration, impact on traffic, and any other information on stay cable inspection methods, factors that you consider important repairs, and testing would be a useful tool? not known

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Sitka Harbor Bridge Sitka, Alaska Questionnaire Results Alaska Survey performed in 2004 Q4-11: Type of cable sheathing used? no Sitka Harbor Bridge, Sitka, no sheathing Q4-20: Do cables have other dampers (other Alaska than viscous or neoprene rings) to control Q4-12: Have rainwind-induced cable State/Province: Alaska vibrations? vibrations been observed on this bridge? Agency: Alaska DOT no not known Respondent: Gary Scarbrough Q4-21: Has cracking of the cable sheathing or Q4-13: Have MTE corrosion problems been sheathing connections been noted? Span Length: 450 ft noted? not applicable Year Built: 1970 no Q4-22: Has cracking or misalignment of the Q4-4: Type of main tension element (MTE)? Q4-14: Do cables have neoprene rings near the guide pipes been noted? top and bottom anchorages? other--galvanized bridge strand not known no Q4-5: Coating/treatment on main tension Q4-23: If there is protective tape wrapped element within free length of cable? Q4-15: If there are neoprene rings on the around the cable sheathing; have there been 79 cables; have there been any reports of galvanized steel reports of deterioration of the tape? movements of the rings out of their positions? Q4-6: Are the coatings/treatments on main not applicable not applicable tension element discontinued or removed Q4-24: Have any problems associated with within the anchorage zone? Q4-16: Has moisture been found in any of the neoprene boots been noted? internal components of stay cables such as the not known bottom anchorage areas? no Q4-7: Type of grout used? yes--area around each cable was filled with Q4-25: Types of non-destructive tests that any not known grease of the cables on this bridge have been subjected to? Q4-8: Are filler materials used in the Q4-17: Has fatigue of MTE or other anchorage zone? components of stay cables been observed? vibration-based force measurements yes--other, liquid polymer sealer no Q4-26: Types of sensor-based, long-term monitoring performed on the cables? Q4-9: Type of anchorage? Q4-18: Do the cables have viscous dampers installed at deck or tower levels? not performed conical socket with wedges no Q4-27: Have the cables on this bridge (or any Q4-10: Do cables go over "saddles" on the of their components) been repaired? pylons? Q4-19: Do the cables have cross cables installed between them? no

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Sitka Harbor Bridge Sitka, Alaska Questionnaire Results Alaska Survey performed in 2004 no--during mid-1990s cables were removed, inspections, laser-based force measurements, Q11: What do you see as the single most inspected, and replaced after no defects X-ray imaging, etc. If possible, please important problem in stay cable maintenance? observed. comment on issues such as practicality, cost, Access to upper cable anchorage duration, impact on traffic, and any other Q4-28: Has the sheathing been partially factors that you consider important. Q12: Please comment on any other methods for removed on any of the cables to examine inspections, testing, monitoring, and repair of condition of grout (if applicable) and/or the The fundamental frequency of the cables was stay cable (including conventional methods) MTE? recorded. Alaska DOT&PF will monitor the that you have found beneficial and are not cables and attempt to determine if the not applicable listed above. fundamental frequency of the cables has Q4-29: Can the strands or cables be replaced if changed. N/A needed? Q7: Please comment on the effectiveness of Additional comments? yes any cable vibration control measures that you may be familiar with. Examples include no answer Q4-30: Do you have an inspection and installation of cross cables, viscous dampers, maintenance manual for this bridge? neoprene rings, etc. no 80 N/A Q5: Based on your experience and in general, Q8: Please comment on the effectiveness of do you believe that the current inspection, any sensor-based, long-term monitoring testing, monitoring, and repair methods systems for stay cables that you may be available to you for stay cables are effective familiar with. Examples include acoustic and adequate? monitoring, vibration monitoring, force not known--cables on both bridges were measurements, strain measurements, etc. inspected during the mid-1990s. Cables on N/A Captain William Moore were replaced due to an upgrade of the structure. Cables on the Q9: What would you recommend that the cable Sitka Harbor Bridge were removed, inspected, suppliers incorporate into their systems to make and reinstalled. No problems were reported cables more accessible and inspectable? with any of the cables during the mid-1990 N/A inspection. Q10: Do you believe that an up-to-date Q6: Please comment on the effectiveness of resource such as a national database of any non-destructive test methods for information on stay cable inspection methods, inspections of stay cables that you may be repairs, and testing would be a useful tool? familiar with. These methods include (but are not limited to) ultrasonic testing, magnetic yes

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Captain William Moore Bridge, Skagway Questionnaire Results Alaska Survey performed in 2004 Q4-11: Type of cable sheathing used? no Captain William Moore Bridge, no sheathing Q4-20: Do cables have other dampers (other Skagway than viscous or neoprene rings) to control Q4-12: Have rainwind-induced cable State/Province: Alaska vibrations? vibrations been observed on this bridge? Agency: Alaska DOT no not known Respondent: Gary Scarbrough Q4-21: Has cracking of the cable sheathing or Q4-13: Have MTE corrosion problems been sheathing connections been noted? Span Length: 300 ft noted? not applicable Year Built: 1975 no Q4-22: Has cracking or misalignment of the Q4-4: Type of main tension element (MTE)? Q4-14: Do cables have neoprene rings near the guide pipes been noted? top and bottom anchorages? other--ASTM Desig A586-86 not known no Q4-5: Coating/treatment on main tension Q4-23: If there is protective tape wrapped element within free length of cable? Q4-15: If there are neoprene rings on the around the cable sheathing; have there been 81 cables; have there been any reports of galvanized steel reports of deterioration of the tape? movements of the rings out of their positions? Q4-6: Are the coatings/treatments on main not applicable not applicable tension element discontinued or removed Q4-24: Have any problems associated with within the anchorage zone? Q4-16: Has moisture been found in any of the neoprene boots been noted? internal components of stay cables such as the not known bottom anchorage areas? no Q4-7: Type of grout used? yes--area around each cable was filled with Q4-25: Types of non-destructive tests that any not known grease. of the cables on this bridge have been subjected to? Q4-8: Are filler materials used in the Q4-17: Has fatigue of MTE or other anchorage zone? components of stay cables been observed? vibration-based force measurements yes, grease no Q4-26: Types of sensor-based, long-term monitoring performed on the cables? Q4-9: Type of anchorage? Q4-18: Do the cables have viscous dampers installed at deck or tower levels? not performed conical socket with wedges no Q4-27: Have the cables on this bridge (or any Q4-10: Do cables go over "saddles" on the of their components) been repaired? pylons? Q4-19: Do the cables have cross cables installed between them? no

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Captain William Moore Bridge, Skagway Questionnaire Results Alaska Survey performed in 2004 Bridge redesigned for higher load capacity. X-ray imaging, etc. If possible, please Q11: What do you see as the single most New cables were installed during mid-1990s. comment on issues such as practicality, cost, important problem in stay cable maintenance? duration, impact on traffic, and any other Q4-28: Has the sheathing been partially Access to upper cable anchorage factors that you consider important. removed on any of the cables to examine Q12: Please comment on any other methods for condition of grout (if applicable) and/or the The fundamental frequency of the cables was inspections, testing, monitoring, and repair of MTE? recorded. Alaska DOT&PF will monitor the stay cable (including conventional methods) cables and attempt to determine if the not applicable that you have found beneficial and are not fundamental frequency of the cables has listed above. Q4-29: Can the strands or cables be replaced if changed. needed? N/A Q7: Please comment on the effectiveness of yes any cable vibration control measures that you Additional comments? may be familiar with. Examples include Q4-30: Do you have an inspection and installation of cross cables, viscous dampers, no answer maintenance manual for this bridge? neoprene rings, etc. no 82 N/A Q5: Based on your experience and in general, Q8: Please comment on the effectiveness of do you believe that the current inspection, any sensor-based, long-term monitoring testing, monitoring, and repair methods systems for stay cables that you may be available to you for stay cables are effective familiar with. Examples include acoustic and adequate? monitoring, vibration monitoring, force not known--cables on both bridges were measurements, strain measurements, etc. inspected during the mid-1990s. Cables on N/A Captain William Moore were replaced due to an upgrade of the structure. Cables on the Q9: What would you recommend that the cable Sitka Harbor Bridge were removed, inspected, suppliers incorporate into their systems to make and reinstalled. No problems were reported cables more accessible and inspectable? with any of the cables during the mid-1990 N/A inspection. Q10: Do you believe that an up-to-date Q6: Please comment on the effectiveness of resource such as a national database of any non-destructive test methods for information on stay cable inspection methods, inspections of stay cables that you may be repairs, and testing would be a useful tool? familiar with. These methods include (but are not limited to) ultrasonic testing, magnetic yes inspections, laser-based force measurements,

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Sacramento River (Meridian) Questionnaire Results California Survey performed in 2004 Q4-10: Do cables go over "saddles" on the Q4-19: Do the cables have cross cables Sacramento River (Meridian) pylons? installed between them? State/Province: California yes no Agency: Caltrans Q4-11: Type of cable sheathing used? Q4-20: Do cables have other dampers (other than viscous or neoprene rings) to control Respondent: Erol C. Kaslan no sheathing vibrations? Span Length: 180 ft Q4-12: Have rainwind-induced cable Cables utilize clamps near the saddles to vibrations been observed on this bridge? Year Built: 1977 retain separation of the cable groups--these no may provide some unintentional damping. Q4-4: Type of main tension element (MTE)? Q4-13: Have MTE corrosion problems been Q4-21: Has cracking of the cable sheathing or steel wire noted? sheathing connections been noted? Q4-5: Coating/treatment on main tension no N/A element within free length of cable? Q4-14: Do cables have neoprene rings near the Q4-22: Has cracking or misalignment of the galvanized steel 83 top and bottom anchorages? guide pipes been noted? Q4-6: Are the coatings/treatments on main no N/A tension element discontinued or removed within the anchorage zone? Q4-15: If there are neoprene rings on the Q4-23: If there is protective tape wrapped cables; have there been any reports of around the cable sheathing; have there been no movements of the rings out of their positions? reports of deterioration of the tape? Q4-7: Type of grout used? N/A N/A grout not used Q4-16: Has moisture been found in any of the Q4-24: Have any problems associated with Q4-8: Are filler materials used in the internal components of stay cables such as the neoprene boots been noted? anchorage zone? bottom anchorage areas? The neoprene seals noted above that retain yes, grease not tested, not known grease in the anchorage areas leak. Q4-9: Type of anchorage? Q4-17: Has fatigue of MTE or other Q4-25: Types of non-destructive tests that any components of stay cables been observed? of the cables on this bridge have been subjected other--main cables are swedged onto a steel to? conical threaded coupler that is attached to a no threaded HS steel rod, which uses a spherical X-ray; primary inspection method is VT. Q4-18: Do the cables have viscous dampers anchor socket and anchor nut to provide "MINAC" radiographic inspection was used installed at deck or tower levels? anchorage connection. This system appears once in 1989 to inspect the swedged to be uniquely designed. no

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Sacramento River (Meridian) Questionnaire Results California Survey performed in 2004 anchorage components as a demonstration of inspections of stay cables that you may be Q10: Do you believe that an up-to-date the technology. familiar with. These methods include (but are resource such as a national database of not limited to) ultrasonic testing, magnetic information on stay cable inspection methods, Q4-26: Types of sensor-based, long-term inspections, laser-based force measurements, repairs, and testing would be a useful tool? monitoring performed on the cables? X-ray imaging, etc. If possible, please yes not performed comment on issues such as practicality, cost, duration, impact on traffic, and any other Q11: What do you see as the single most Q4-27: Have the cables on this bridge (or any factors that you consider important. important problem in stay cable maintenance? of their components) been repaired? Used radiographic testing once on this Inspection and condition evaluation of no structure. It was costly and impractical, but anchorages Q4-28: Has the sheathing been partially did appear to give satisfactory results. Would Q12: Please comment on any other methods for removed on any of the cables to examine not use this method for routine inspections on inspections, testing, monitoring, and repair of condition of grout (if applicable) and/or the this bridge. stay cable (including conventional methods) MTE? Q7: Please comment on the effectiveness of that you have found beneficial and are not N/A any cable vibration control measures that you listed above. 84 may be familiar with. Examples include Q4-29: Can the strands or cables be replaced if installation of cross cables, viscous dampers, Engineering judgment and experience seem to needed? neoprene rings, etc. prevail in determining appropriate inspection and maintenance strategies. yes--as this swing bridge only fully utilizes no answer the cables to support the spans in the open Additional comments? condition, cable replacement would be Q8: Please comment on the effectiveness of relatively straightforward. any sensor-based, long-term monitoring systems for stay cables that you may be Q4-30: Do you have an inspection and familiar with. Examples include acoustic maintenance manual for this bridge? monitoring, vibration monitoring, force no measurements, strain measurements, etc. Q5: Based on your experience and in general, Acoustic monitoring appears to have great do you believe that the current inspection, value and promise. Would recommend that testing, monitoring, and repair methods this technology be fully developed. available to you for stay cables are effective Q9: What would you recommend that the cable and adequate? suppliers incorporate into their systems to make not known cables more accessible and inspectable? Q6: Please comment on the effectiveness of Fiber optic strain gauges and redundant any non-destructive test methods for systems

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Br. 1-902, SR1 over the Chesapeake and Delaware Canal, St. Georges, New Castle County, Delaware Questionnaire Results Survey performed in 2004 Delaware Q4-10: Do cables go over "saddles" on the inspectors to believe moisture is infiltrating Br. 1-902, SR-1 over the pylons? the cable stay system. Chesapeake and Delaware yes Q4-17: Has fatigue of MTE or other Canal, St. Georges, New Castle components of stay cables been observed? Q4-11: Type of cable sheathing used? County, Delaware steel pipe no State/Province: Delaware Q4-18: Do the cables have viscous dampers Q4-12: Have rainwind-induced cable installed at deck or tower levels? Agency: Delaware DOT vibrations been observed on this bridge? no Respondent: Douglas Finney no Q4-19: Do the cables have cross cables Span Length: 750 ft Q4-13: Have MTE corrosion problems been installed between them? noted? Year Built: 1995 no not known--moisture infiltration is suspected Q4-4: Type of main tension element (MTE)? however, due to the limitations of available Q4-20: Do cables have other dampers (other 85 seven-wire steel strand inspection methods; definitive evidence of than viscous or neoprene rings) to control corrosion is not available. vibrations? Q4-5: Coating/treatment on main tension element within free length of cable? Q4-14: Do cables have neoprene rings near the no top and bottom anchorages? bare Q4-21: Has cracking of the cable sheathing or yes sheathing connections been noted? Q4-6: Are the coatings/treatments on main tension element discontinued or removed Q4-15: If there are neoprene rings on the yes, sheathing--cracking of the steel within the anchorage zone? cables; have there been any reports of protective pipe has been noted on the upper- movements of the rings out of their positions? most stay cable of the north pylon. Cracking not applicable has been attributed to the position of a yes--due to loosening of retainers; movement Q4-7: Type of grout used? construction grout vent hole at a high stress observed in outer neoprene ring of anchorage location. cementwater admixtures set. No retaining devices were present. Q4-22: Has cracking or misalignment of the Q4-8: Are filler materials used in the Q4-16: Has moisture been found in any of the guide pipes been noted? anchorage zone? internal components of stay cables such as the bottom anchorage areas? no yes, grout not known--effloresence from anchorages as Q4-23: If there is protective tape wrapped Q4-9: Type of anchorage? well as protective pipe splice sleeves leads around the cable sheathing; have there been conical socket with wedges reports of deterioration of the tape?

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NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Br. 1-902, SR1 over the Chesapeake and Delaware Canal, St. Georges, New Castle County, Delaware Questionnaire Results Survey performed in 2004 Delaware not applicable--protective steel pipe is yes--out of position neoprene dampers have not limited to) ultrasonic testing, magnetic painted. been repositioned and set screws have been inspections, laser-based force measurements, installed to secure the position of the outer X-ray imaging, etc. If possible, please Q4-24: Have any problems associated with neoprene damper rings on all cable stays. comment on issues such as practicality, cost, neoprene boots been noted? duration, impact on traffic, and any other Q4-28: Has the sheathing been partially yes--minor tearing of one neoprene boot has factors that you consider important. removed on any of the cables to examine been observed. condition of grout (if applicable) and/or the The presence of the steel protective pipe limits Q4-25: Types of non-destructive tests that any MTE? the effectiveness of many available testing of the cables on this bridge have been subjected methods, particularly magnetic based no--limited investigation of the cable stay to? methods. As noted above, X-ray imaging of grout has been performed via the open the cable stays was considered and dismissed. other--borescope has been utilized to view the construction grout vents in the saddle pipe Several concerns were encountered with this guidepipe area of select cable stays for area of the cable stay. method including protection of public and moisture, fatigue, deterioration, and working personnel during the exposure, Q4-29: Can the strands or cables be replaced if corrosion. An attempt was made to remove access and holding the equipment at the needed? 86 select anchorage caps; however, grout inside higher elevations of the cable stay, and the anchorage caps made removal difficult. yes--The original design accounted for the scheduling of the equipment. Interpretation replacement of the stay cables (one at a time). of the image was also a concern. It is believed High-powered X-ray inspection of the cable stays was considered. This method has not Q4-30: Do you have an inspection and that the multiple materials (steel, grout, steel been employed due to concerns for protection maintenance manual for this bridg e? strand) that comprise the cable stays of the public and personnel during testing, combined with the changing geometry would yes make interpretation of the image difficult and access limitations, uncertainty of the results of such investigations due to the complicated Q5: Based on your experience and in general, would not allow for an accurate geometry of the subject area. do you believe that the current inspection, understanding of the conditions. Our testing, monitoring, and repair methods understanding is that the X-ray imaging Q4-26: Types of sensor-based, long-term would only be able to detect gross section loss available to you for stay cables are effective monitoring performed on the cables? of the stay and is not precise enough to and adequate? not performed. Vibration monitoring discern the onset or early stages of corrosion. no--use of the steel protective pipe limits the Finally, when the X-ray imaging method was equipment has been installed on the cable inspection methods available to investigate the considered, it only allowed a view of a discrete stays by the FHWA. However, this equipment condition of the stay cables. section of the cable stay as opposed to a global is currently not operating and data are not available. Q6: Please comment on the effectiveness of or "traveling" operation whi ch would allow any non-destructive test methods for an investigation of the entire length of the Q4-27: Have the cables on this bridge (or any cable stay. Implementation of laser-based inspections of stay cables that you may be of their components) been repaired? cable stay force measurements are being familiar with. These methods include (but are

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195 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q5 Q6 Q7 ungrouted stays with capacity to add approximately 5% strand in the future and the stays are fitted with engineered vibration suppression devices. Internal hydraulic and external hydraulic damping devices are being installed and provisions provide for the possible addition of cable ties (damping ropes) in the future on selected longer stays that have been identified as having the potential to experience parametric excitation

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196 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Questions: Q8 Please comment on the effectiveness of any sensor-based, long-term monitoring systems for stay cables that you may be familiar with. Examples include acoustic monitoring, vibration monitoring, force measurements, strain measurements, etc. Q9 What would you recommend that the cable suppliers incorporate into their systems to make cables more accessible and inspectable? Q10 Do you believe that an up-to-date resource such as a national database of information on stay cable inspection methods, repairs, and testing would be a useful tool? Responses: State Bridge Q8 Q9 Q10 Alabama Cochrane Africatown Check with A.G. Provide access on not known Lichtenstein inside and outside of tower anchorage Alaska Sitka Harbor Bridge, Sitka, N/A N/A yes Alaska Alaska Captain William Moore N/A N/A yes Bridge, Skagway California Sacramento River Acoustic monitoring Fiber optic strain yes (Meridian) appears to have great gauges and redundant value and promise. systems Would recommend that this technology be fully developed Delaware Br. 1-902, SR-1 over the The current sensor- We would recommend yes Chesapeake and Delaware based, long-term the development of Canal, St. Georges, New monitoring system individual strand Castle County, Delaware installed on the bridge monitoring capabilities is not operable and which encompass the therefore comment strands from anchorage cannot be made. The to anchorage department is considering the addition of force measurement (deck-based laser method) to the list of inspection items required for the bridge Florida Dame Point Bridge none Not familiar with this yes Georgia Talmadge Memorial These are all effective, For non-box bridges, an yes Bridge, Savannah but they are generally inspection traveler expensive and have not should be installed on been used on Georgia's the cable-stayed bridge. bridges This should be done by the owner Georgia Sidney Lanier Bridge, These are all effective, For non-box bridges, an yes Brunswick but they are generally inspection traveler expensive and have not should be installed on been used on Georgia's the cable-stayed bridge. bridges This should be done by the owner Illinois Quincy Bayview Bridge at An acoustic monitoring no answer yes Quincy, IL system was installed (approximately a year and a half ago) on one- fourth of the stays of the Quincy Bayview Bridge. This was done due to concern over water in the cable

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197 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q8 Q9 Q10 anchorages and to evaluate the technology. The system appears to be functioning properly and so far has provided information on one "event" that has been classified as a wire break Illinois Clark Bridge at Alton, IL An acoustic monitoring no answer yes system was installed (approximately a year and a half ago) on one- fourth of the stays of the Quincy Bayview Bridge. This was done due to concern over water in the cable anchorages and to evaluate the technology. The system appears to be functioning properly and so far has provided information on one "event" that has been classified as a wire break Indiana 46-03-7495 EBL Have not used any yet. ?? yes Indiana I65-68-7910 Have not used any yet. ?? yes Iowa Burlington, IA Have not had no answer yes experience with long- term monitoring Kentucky William Natcher Bridge, There are two problems It does not seem yes--the resource does Owensboro, KY on the monitoring possible that the cable not exist so far. We systems. First, who suppliers can do any (Parsons Brinkerhoff) will analyze the large more. (PB) are developing them amount of data right now. (PB) collected? Second, how long will the sensors and the computer system last? We are talking about 100-year life span. The reality is that the monitoring system will fail or become obsolete within approximately 10 years when the bridge is not expected to have any problems. (PB) Kentucky William H. Harsha Bridge, There are two problems It does not seem yes--the resource does Maysville, KY on the monitoring possible that the cable not exist so far. We systems. First, who suppliers can do any (Parsons Brinkerhoff) will analyze the large more. (PB) are developing them amount of data right now. (PB) collected? Second, how long will the sensors and the computer system last? We are talking about 100-year life span. The reality is that the monitoring system will fail or become obsolete within

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198 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q8 Q9 Q10 approximately 10 years when the bridge is not expected to have any problems. (PB) Louisiana Mississippi River Bridge at Vibration monitoring I like the idea of yes Luling, LA has been ongoing at hermetically sealed, Luling for 20 years in ungrouted cables with anticipation of a fiber optic sensors hurricane striking the throughout or exposed bridge--no significant wire that can be directly long duration winds inspected have occurred Mississippi No comment/not No comment/no Not known/yes known comment Massachusetts Leonard P. Zakim Bunker none Transparent outer pipe, yes Hill Bridge, Boston, MA eliminate grout Missouri Bill Emerson Memorial MoDOT has no related Perhaps a permanent yes Bridge, Cape Girardeau experience load cell that would permit real-time readings of cable forces at any time during the life of the bridge Ohio Maumee River Bridge, no answer Access is a very sharp Not known--while Toledo two-edged sword. If information can be you can more easily useful, it can also be access the cable, so can misinterpreted. The best corrosive elements (not resource is direct to mention potential contact with those who terrorist/security have hands-on considerations) knowledge related to the specific area that an individual may be making inquiries South Carolina Cooper River Bridge none Include a maintenance yes manual with clear instructions for both specific wires or full cables Texas Veterans Memorial Bridge The department has Current grouted and yes installed an acoustic sheathed systems do not monitoring system to allow for visual identify possible wire inspection. New stay breaks at the Fred systems (perhaps Hartman Bridge. The ungrouted, unsheathed system seems to work systems consisting of well and has identified bare corrosion-resistant several possible wire tension members) need breaks. Prior to its to be developed that installation, the system allow for inspection of was tested on a cable the entire stay length. mock-up at the Research is also needed Ferguson Structural to develop rapid, Lab of the University of economical evaluation Texas at Austin, where (NDE) methods to research is underway to determine conditions of determine the effects of stay cables stay cable vibrations on the fatigue life of the cables. This allowed the department to test the monitoring system to see how accurately it could identify occurrence and location of wire breaks since numerous wire breaks

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199 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q8 Q9 Q10 were generated. The correlation between the monitoring system results and the autopsied cables was very good Texas Fred Hartman Bridge The department has Current grouted and yes installed an acoustic sheathed systems do not monitoring system to allow for visual identify possible wire inspection. New stay breaks at the Fred systems (perhaps Hartman Bridge. The ungrouted, unsheathed system seems to work systems consisting of well and has identified bare corrosion resistant several possible wire tension members) need breaks. Prior to its to be developed that installation, the system allow for inspection of was tested on a cable the entire stay length. mock-up at the Research is also needed Ferguson Structural to develop rapid, Lab of the University of economical evaluation Texas at Austin, where (NDE) methods to research is underway to determine conditions of determine the effects of stay cables stay cable vibrations on the fatigue life of the cables. This allowed the department to test the monitoring system to see how accurately it could identify occurrence and location of wire breaks since numerous wire breaks were generated. The correlation between the monitoring system results and the autopsied cables was very good Virginia I-295 over James River no comments no comments yes (VarinaEnon Bridge) Washington Gum Street--Kennewick, N/A unknown yes WA Washington TheaFoss Tacoma, WA N/A unknown yes Wisconsin Sixth Street Viaduct, North not applicable no answer yes Cable Stay Wisconsin Sixth Street Viaduct, South not applicable no answer yes Cable Stay Alberta/Calgary Prince's Island (Pedestrian) Have not used vibration no answer yes monitoring on a long- term basis. Has only been used for short durations to determine frequency and magnitude, etc. Alberta/Calgary Carburn Park (Pedestrian) Have not used vibration no answer yes monitoring on a long- term basis. Has only been used for short durations to determine frequency and magnitude, etc. Alberta/Calgary McMahon (Pedestrian) Have not used vibration no answer yes monitoring on a long- term basis. Has only

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200 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q8 Q9 Q10 been used for short durations to determine frequency and magnitude, etc. Alberta/Calgary Fox Hollow (Pedestrian) Have not used vibration no answer yes monitoring on a long- term basis. Has only been used for short durations to determine frequency and magnitude, etc. Alberta/Calgary Stoney Trail (Pedestrian) Have not used vibration no answer yes monitoring on a long- term basis. Has only been used for short durations to determine frequency and magnitude, etc. British Columbia Alex Fraser Bridge Acoustic monitoring Our cables are yes may be cost-effective reasonably accessible, for older structures. For inspectable. Possibly a new structures, cost of closeable drain at the monitoring outweighs lower end of the cable benefits, and may be to allow visual compromised by other inspection, sample noise (rehab, banging, collection, testing for etc.) on the structure corrosion product of any water in the cable sheaths Manitoba/Winnipeg Esplanade Riel Not enough experience Different corrosion yes to comment at this time protection system at the anchorages that permits easier visual inspection. Removable sections of the HDPE and Vandal Tubes would make it easier to inspect strands near the anchorages New Brunswick Hawkshaw Monitoring of no answer yes deflection of bridge by student at Nackawic New Brunswick Longs Creek #1 Monitoring of no answer yes deflection of bridge by student at Nackawic New Brunswick Nackawic River Monitoring of no answer yes deflection of bridge by student at Nackawic Quebec, Canada Galipeault No long-term no answer yes monitoring on our stay cable bridges at the present time Quebec, Canada Papineau No long-term no answer yes monitoring on our stay cable bridges at the present time Quebec, Canada Price Freyssinet We believe acoustical Ability to detension, yes monitoring is an inspect, and retension effective method to individual strands record wire failures. Ability to detension, Permanent load cells remove, and replace are good for monitoring individual strands. loads, especially with Ability to add strands to unbonded monostrands each cable or cable when it can be group (avg. 5%) established that the load

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201 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q8 Q9 Q10 is equal in all individual strands within reasonable tolerances such that by monitoring one strand, the load in cable is known

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202 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS Questions: Q11 What do you see as the single most important problem in stay cable maintenance? Q12 Please comment on any other methods for inspections, testing, monitoring, and repair of stay cable (including conventional methods) that you have found beneficial and are not listed above. Additional Comments? Responses: State Bridge Q11 Q12 Additional Comments Alabama Cochrane Africatown Stay anchors. (Access no answer and rainwind-induced oscillation) Alaska Sitka Harbor Bridge, Sitka, Access to upper cable N/A no answer Alaska anchorage Alaska Captain William Moore Access to upper cable N/A no answer Bridge, Skagway anchorage California Sacramento River Inspection and Engineering judgment (Meridian) condition evaluation of and experience seem to anchorages prevail in determining appropriate inspection and maintenance strategies Delaware Br. 1-902, SR-1 over the Effective corrosion Chesapeake and Delaware barriers that do not Canal, St. Georges, New interfere with the ability Castle County, Delaware to adequately inspect and assess the health of the cable stay system on a regular interval and within practical means Florida Dame Point Bridge Accessibility for Man-lift truck inspection and maintenance Georgia Talmadge Memorial Access to the cable Television endoscope- Bridge, Savannah anchorages type cameras for access to guide pipes at bridge deck level is helpful Georgia Sidney Lanier Bridge, Access to the cable Television endoscope- Brunswick anchorages type cameras for access to guide pipes at bridge deck level is helpful Illinois Quincy Bayview Bridge at Uncertainty of cable no answer Quincy, IL condition and anchorages Illinois Clark Bridge at Alton, IL Uncertainty of cable no answer condition and anchorages Indiana 46-03-7495 EBL Inspection, access, no answer testing, cost Indiana I65-68-7910 Inspection, access, no answer testing, cost Iowa Burlington, IA The inability to inspect no answer the elements inside the cable and the anchorage areas Kentucky William Natcher Bridge, Inspecting the cable none Comments followed by Owensboro, KY anchors. (PB) (DKD) were made by Inspecting grout-filled Darrell Dudgeon of cables. (DKD) KYTC. Comments followed by (PB) were made by Ruchu Hsu,

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203 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q11 Q12 Additional Comments P.E. of Parsons Brinkerhoff Quade and Douglas, Inc. Consulting Engineers who was the lead design engineer for the Owensboro Bridge Kentucky William H. Harsha Bridge, Inspecting the cable none Comments followed by Maysville, KY anchors. (PB) (DKD) were made by Inspecting grout-filled Darrell Dudgeon of cables. (DKD) KYTC. Comments followed by (PB) were made by Ruchu Hsu, P.E. of Parsons Brinkerhoff Quade and Douglas, Inc. Consulting Engineers who was the lead design engineer for the Owensboro Bridge Louisiana Mississippi River Bridge at The hidden nature of no answer no answer Luling, LA the system Mississippi No comment/we do not N/A and N/A have enough experience in this area to comment Massachusetts Leonard P. Zakim Bunker Access for inspection Stay cable anchorage no answer Hill Bridge, Boston, MA design should allow for accessibility for inspection. Inspection, maintenance, and replacement should be addressed during design Missouri Bill Emerson Memorial The integrity of the MoDOT has no related Bridge, Cape Girardeau stays. Grouted cables experience are impossible to inspect with a non- destructive technique (i.e., one that does not require removal of sheathing and grout) thus, it is impossible to identify corrosion problems early Ohio Maumee River Bridge, The largest "problem" no answer no answer Toledo with stay cables is that they are widely perceived as "a problem" rather than just another bridge member with specific needs and characteristics. Stay cables have been placed unnecessarily "on a pedestal." While they are a very important bridge member, in current designs they are highly redundant, overtested, and (relatively) easily replaced. There is no other major bridge member that fits into all three of these categories. Let's not

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204 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q11 Q12 Additional Comments promote the feeling that Stays are "a maintenance problem" South Carolina Cooper River Bridge Provide end caps that no answer are easily removed and fully protected against corrosion Texas Veterans Memorial Bridge Ability to determine the no answer effectiveness and remaining life of corrosion protection systems for main tension elements. The configuration and construction techniques make evaluation and inspection using non- destructive techniques almost impossible Texas Fred Hartman Bridge Ability to determine the no answer effectiveness and remaining life of corrosion protection systems for main tension elements. The configuration and construction techniques make evaluation and inspection using non- destructive techniques almost impossible Virginia I-295 over James River Lack of familiarity with no answer (VarinaEnon Bridge) this type of construction by the department's staff which requires assistance from the consultant community in the inspection of these elements Washington Gum Street--Kennewick, none yet N/A WA Washington TheaFoss Tacoma, WA none yet N/A Wisconsin Sixth Street Viaduct, North Cannot inspect cables Four strands (one at Cable Stay without pulling strand each pylon) will be every 10 years removed every 10 years starting in 2014 to check for corrosion/rusting Wisconsin Sixth Street Viaduct, South Cannot inspect cables Four strands (one at Cable Stay without pulling strand each pylon) will be every 10 years removed every 10 years starting in 2014 to check for corrosion/rusting Alberta/Calgary Prince's Island (Pedestrian) Access for inspection no answer The five bridges and actual testing identified are all pedestrian structures. Three over water and two over roadways Alberta/Calgary Carburn Park (Pedestrian) Access for inspection no answer The five bridges and actual testing identified are all pedestrian structures. Three over water and two over roadways Alberta/Calgary McMahon (Pedestrian) Access for inspection no answer The five bridges and actual testing identified are all

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205 NCHRP SYNTHESIS TOPIC 35-07--INSPECTION AND MAINTENANCE OF BRIDGE STAY CABLE SYSTEMS State Bridge Q11 Q12 Additional Comments pedestrian structures. Three over water and two over roadways Alberta/Calgary Fox Hollow (Pedestrian) Access for inspection no answer The five bridges and actual testing identified are all pedestrian structures. Three over water and two over roadways Alberta/Calgary Stoney Trail (Pedestrian) Access for inspection no answer The five bridges and actual testing identified are all pedestrian structures. Three over water and two over roadways British Columbia Alex Fraser Bridge Detecting corrosion in no comment Have had leakage of cables, maintenance of wax blocking sheaths and boots compound at bottom anchorages during hot weather Manitoba/Winnipeg Esplanade Riel Corrosion at the no answer anchorages New Brunswick Hawkshaw Migration of water into no answer cable strands New Brunswick Longs Creek #1 Migration of water into no answer cable strands New Brunswick Nackawic River Migration of water into no answer cable strands Quebec, Canada Galipeault Fatigue no answer We have had a serious problem on Galipeault bridge no. 1--failure of an anchorage plate at one abutment (corrosion and fatigue failure). Emergency repairs were performed Quebec, Canada Papineau Fatigue no answer We have had a serious problem on Galipeault bridge no. 1--failure of an anchorage plate at one abutment (corrosion and fatigue failure). Emergency repairs were performed Quebec, Canada Price We also had a failure of an anchorage plate on Price bridge (no. 3) during the 1988 Saguenay earthquake (ML = 6.0). It was the first documented structural damage to a steel bridge caused by an earthquake in Canada Freyssinet Inspectability in the no answer anchorage area