Mizzou Civil and Environmental Engineering
Developing a Bridge Preservation Plan for Small Cities Glenn A. Washer, Ph.D. Department of Civil and Environmental Engineering University of Missouri [email protected]
Agenda • Introduction to Columbia, MO • Challenges for a small city • Design of preservation program – Information sources – Bridge preservation inspection program – Short term and long term activities – Selection rationale
• Conclusion
City of Columbia, MO • Fourth largest city in Missouri – 120,000 people – 35,000 students at the University of Missouri
• Educational center – University of Missouri • • • • •
Law Engineering Medical Veterinary Medicine Life sciences
– Stephens College – Columbia College
City Department of Public Works • • • • • • • • • • •
Engineering Maintain sidewalks Mowing Maintaining signage Storm response Maintain bridges New bridge construction Rehab and repair Pavements Etc….. Resources are limited
Challenges for a small city • Staffing is limited and responsibility is very diversified • Community relations and response are a major activity – Overseeing a bridge repair in the morning – Fixing a pothole in a neighborhood in the afternoon
• Worst-first approach • How can we reduce the number of repair / rehabs for our bridges • Push-off major repairs to preserve limiting funding – With limited staff and resources
• Practical and implementable with current staffing
5
Bridges in the City of Columbia, MO
Bridge population in Columbia, MO • 38 bridges and culverts in the city – 29 bridges and 9 culverts
• Average age of 32 years – 1/3 of the bridges are less than 15 years old – Almost 50% of the bridge decks are rated 7 or higher
Bridges with issues….
Unusual bridges….
New bridges with good durability characteristics
Goal of the Project Extend service life of the local bridges in Columbia, MO
Objective of the Project Develop guidelines for bridge maintenance and preservation focused on practical and implementable technologies and procedures such as; • Bridge deck flushing • Fog and seal program • Crack sealers
Bridge Preservation ..actions or strategies that prevent, delay, or reduce deterioration of bridge elements; restore the function of existing bridges; keep bridges in good condition; and extend their useful life. Preservation actions may be preventative or condition-driven.” Maintaining a bridge in good condition can extend the service life of the bridge and has proven to be cost effective as compared with allowing bridge to deteriorate, leading to more extensive and costly repairs.
Preservation Classification Schematic diagram of bridge preservation activities
Typical bridge preservation activities • Focus: preventing or slowing corrosion damage • Moisture and chlorides
Bridge Component All
Deck
Superstructure
Substructure
Description Sweeping, power washing or flushing Deck washing Deck sweeping Drainage cleaning / repair Joint Cleaning Deck sealing Crack sealing Deck Patching Asphalt Overlay with membrane Joint seal replacement Drainage repair Bridge approach restoration Seat and beam end washing Spot or Zone painting Debris removal Scour counter measures Clearing debris
Preventative Maintenance Type
Action Frequency (yrs) 1-2
Cyclical
1 1 1 1 7-10 4-5 1-2
Condition Based
12-15 10 1
Cyclical
Condition based Condition based
2 2 As needed As needed As needed
• We have heard about preservation, but how do we decide which preservation actions to take, and when? – Which bridges, when – What are short term actions and longer terms actions that are appropriate and practical for the city?
INFORMATION SOURCES FOR PUBLIC WORKS • MoDOT performs NBIS inspections for the state – Notes sections contain preservation and maintenance activities
• Inspection of bridges – Staffing is limited and responsibilities are diversified – Engineer covers all aspect of the roadways, from pavements to cutting vegetation, developing new projects, and construction project oversite
Bridge Preservation Inspection Program (BPIP) • Bridge Preservation Inspection Program – Used to identify condition-based preservation needs – Limited training required – Simple guidelines that can be executed by summer interns • MU students
• A typical inspection could be completed in one hour or less • Is low cost and assist maintenance personnel with identifying where PM activities may be required • BPIP provides additional data on the current needs in the inventory in a practical, low-cost manner
Bridge Preservation Inspection Program BPIP
Vegetation on Bridge ID # 0930009
Visual guide for bridge preservation 1
Question Are there any unsealed cracks in the surface of the deck? Y/N Notes
2
Are there any spalls in the bridge deck that require patching? Y/N Notes
3
Is there debris on the surface of the deck? Y/N Notes
Photograph of Typical Condition
Visual guide for preservation inspection • Photos gather from city of Columbia bridges
20
Current Preservation Needs • Field visits to bridges and culverts yielded a list of current actions
Recommendations • Focus on low-cost activities to prevent deterioration and keep good bridges in good condition • Identify and prioritize PM activities such as cleaning and washing bridges to extend service life • Include a mix of short term, mid-term and long-term PM activities • Recommendations developed based on analysis – Crack sealing – Bridge cleaning – Bridge washing – Deck sealing – Superstructure washing – Clear vegetation – Repair leaking joints
Schedule for Preventative Maintenance • PM activities were prioritized based on – A subjective risk analysis considered the PM activity potential impact, cost, and ease of implementation – Cost was rated as low, medium or high – Impact estimated based on the available literature and engineering judgement – Ease of implementation considered if the activity could be completed by maintenance personnel or temporary workers, or require a contract
Schedule for Preventative Maintenance • Prioritized for impact, cost, ease of implementation Scenario
Seal cracks in bare concrete decks
Clean Decks and drains
Priority
ASAP
12 months
Clean beam seat areas of debris
12 months
Implement bridge deck washing / flushing program
24 months
Rationale Open cracks in the surface of a bridge deck are the most direct pathway for moisture and chlorides to penetrate to reinforcing steel and cause corrosion damage. The sealing of cracks with have an immediate, positive effect on reducing the deterioration of bridges. The activity can be completed with existing maintenance personnel. Sweeping and cleaning of bridge decks will immediately have an effect on reducing the rate of corrosion by removing moisture trapped against the materials. The activity can be completed with existing maintenance personnel or temporary staffing. Clearing beam seats of debris will immediately have an effect on reducing the rate of corrosion by removing moisture trapped against the materials. The activity can be completed with existing maintenance personnel or temporary staffing. Deck washing will have a long-term benefit of reducing the rate of corrosion in bridge elements. The impact of deck washing may be less than impact of simply removing debris from the surface, and the cost is higher.
Selection Criteria BPIP / Inspection results
BPIP / Inspection results BPIP / Inspection results
All bridge decks.
Scenario
Priority
Implement bridge superstructure washing
24 months
Implement a bridge deck sealing program.
24 months
Clear vegetation
Repair leaking joints
36 months
48 months
Rationale Superstructure washing will have a long-term benefit of reducing the rate of corrosion in bridge elements. The impact of superstructure washing is less than the impact of simply removing debris from the surface, and the cost is higher. Access to the areas of the bridge that require washing is also more difficult, and pressure washing is required. Sealing of concrete decks will extend the service life of the deck and have a positive long term effect on the deterioration rate of the deck. However, the costs are higher than other activities, and this may require contract forces to complete the work. Maintenance personal can seal decks with some modest training and procedures. Removing vegetation surrounding or growing onto bridges will diminish the corrosive environment by improving air flow through the structure and not trapping moisture against the surface of the concrete. However, the impact of this activity is much smaller as compared with removing debris or washing bridge elements. Costs are low and maintenance personnel or temporary workers can complete this task. Repairing leaking joints in bridges will reduce deterioration at the beam-ends by preventing water and chlorides from draining directly onto these elements. This will have a impact of extending the service life of the bridge. Requirements depend on the type of joints. Replacing leaking deck seals has a higher cost relative to other PM activities.
Selection Criteria Prioritize steel bridges and bridges with open or leaking joints
See Table 4
BPIP / Inspection results
BPIP / Inspection results
Bridge Cleaning • Includes bridge deck, drainage, and support bearing • Remove debris accumulation to prevent corrosion damage • Lowest cost action
Bridge Washing • Clean/remove debris from decks and beam seats prior to washing • Washing bridge elements with water to remove debris – Pressurized water for superstructure and drainage area – Flooding or pressurized water for the deck
Bridge Superstructure Washing Prioritization • • • • •
For most bridges, bridge washing should focus on the beams ends, bearing and beam seats Surrounding the drains be considered for washing Bridges with leaking joints be prioritized over bridges with sound joints Jointless bridges may not require periodic washing Weathering steel bridges will benefit significantly
Example – Bridge Cleaning and Washing 930022
Example 930022 – replace seal
Crack Sealing • • • • •
Done by crack chasing Includes high molecular methacrylate (HMWM) and other polymers Effective for crack spacing of 2 ft. or greater Lifespan is less than penetrating sealers Reapplication frequency of 3 to 5 years
Which decks should be sealed? • Decks currently in good condition with concrete decks No.
Bridge Federal ID
Design No.
Year built
# of Spans
Deck Type
Wearing Surface
1 2 3 4 5 6 7 8 9 10 11 12 13 14
30593 32732 15429 15437 28793 31461 34416 34784 33734 15423 32428 34415 33540 33735
0930003 0930010 0930018 0930024 0930031 0930032 0930039 0930040 0930036 0930014 0930034 0930038 0930005 0930037
2004 2009 1982 1990 1982 2005 2012 2014 2009 1935 2009 2012 2009 2009
3 2 2 2 1 3 3 4 3 1 3 3 3 3
ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc
PlainConc PlainConc PlainConc PlainConc PlainConc PlainConc PlainConc NotApplic PlainConc PlainConc PlainConc NotApplic NotApplic PlainConc
Recent Deck CS Rating 8 7 7 7 7 7 8 9 8 7 8 7 8 9
Bridge Condition Data • Data-driven PM activities provide increased efficiency by completing condition related activities • MoDOT biennial safety inspection report contains inspector recommendations for maintenance and repair • Recommendations are important inputs to identify condition-related activities – Deck sealing, clearing vegetation and bank protection
MoDOT Preservation Recommendations No.
Bridge Federal ID
Design No.
Inspection Date
1
15392
0930001
04/14/2015
2
15400
0930002
04/23/2015
3
30593
0930003
04/23/2015
4
15409
0930006
4/23/2015
5
15413
0930009
4/23/2015
6 7 8 9
15422 32732 15426 15427
0930013 0930010 0930016 0930017
4/27/2015 4/27/2015 4/23/2015 4/27/2015
10
15429
0930018
4/23/2015
Work Comment
Place bank protection along the north abutment and bank. Repair the deck. Repair the driving surface, waterproof, and place an asphalt wearing surface on the deck. Place rock along the north abutment. Consider replacing the superstructure. Hydrodemolition candidate. Repair the deck and replace the wearing surface. Seal the edge of the deck and beams. Clean out the deck scuppers. Consider replacing the wearing surface. Consider sealing the deck with silane. Replace the wearing surface. Repair the north bank protection Consider sealing the deck with silane and painting the deck edges with an epoxy paint.
Conclusions • Maintaining bridges in good condition can extend the life of a bridge and forestall maintenance, repair and replacement needs • Cost effective as compared with allowing bridge to deteriorate, leading to more costly repairs • Specific recommendations and prioritization for a preservation PM program for bridges in Columbia • Implementation will help the city keep its network of 38 bridges and culverts in good condition using limited resources and meet future needs
Thank you! Questions
MIZ…
MoDOT PM EPG • MoDOT engineering policy guidance for PM activities Preservation Action Superstructure Washing Deck Flushing/Washing Vegetation Control Debris Removal Drainage System Cleanout/repair Spot Painting Deck Sealing Seal concrete cracks
Seal Joints Seal HMA cracks
MoDOT Eng. Guide 771.2 Bridge Cleaning and Flushing 771.2 Bridge Cleaning and Flushing 771.20 Cut and Spray Brush and Vines 771.8 Remove Drift 771.2 Bridge Cleaning and Flushing 771.4 Drain Basin Maintenance 771.14 Spot Painting of Bearings and Piling 771.16 Penetrating Concrete Sealer – Silane 771.17 Concrete Crack Filler - Low Viscosity Polymer (LVP) 771.18 In-Deck Bridge Deck Crack Filler 771.19 Chip Seal to Entire Deck (R322 Bridge Seal Coats Maintenance Planning Guidelines) 771.10 Bridge Joint Sealing - Hot Pour 771.11 Bridge Joint Sealing – Silicone 771.12 Bridge Joint Sealing - Polytite 413.5 Crack Treatment in Bituminous Pavements
Project Activities • Literature search • Contacts within the preservation community – Interviews with state-level bridge owners – Participate in the Midwest Bridge Preservation Partnership
• Field survey of several City of Columbia bridges – Evaluation of City of Columbia needs
• Subjective risk analysis for preventative maintenance (PM) prioritization
Periodic PM activities • Some PM actions need to be repeated over the long term at different intervals. Time Period Short Term (1224 months)
Mid-Term (2572 months)
Long Term (73120 months)
PM Action
Expected Service Life (yrs)
Bridge Selection Criteria
Seal concrete cracks Drainage System Cleanout/repair Deck cleaning and washing
3-5 1
Decks with cracking All bridge decks with drains
1
Clean and wash bridge beam ends, beam seats and bearings Deck Sealing Seal HMA cracks
1-2 10 3-5
All bridges will benefit from cleaning and washing Bridges with accumulated debris and leaking joints; prioritized as noted above Bare concrete decks in good condition Asphalt decks with cracking
Seal Joints Spot Painting Reseal cracks after 3-5 years.
7-10 7 3-5
Based on inspection results Bridges with damage at the beam ends Cyclical
Reseal decks after 7 to10 years
Penetrating Sealers • Reducing concrete diffusivity and sealing small cracks to reduce capillary actions • Applied after 3 to 6 months after construction • Periodic reapplication necessary 7 to 10 yrs • Includes silanes, siloxenes, siliconates, silicones, and linseed oil • Seal tight crack 0.010 in wide or less
Penetrating Sealers and Crack Sealing • MoDOT deck sealing recommendation (EPG 771.15) New Decks and Decks with minimal cracking Decks with hairline cracks < 1/128” (0.008 in.) wide Decks with cracks >1/128” (0.008 in.) wide Decks with cracks >1/64” (0.016 in.) wide
EPG 771.16 Penetrating Concrete Sealer - Silane EPG 771.17 Concrete Crack Filler -Low Viscosity Polymer (LVP) EPG 771.18 In-Deck Bridge Deck Crack Filler EPG 771.19 Chip Seal to Entire Deck
• Service life of penetrating sealers found by different researchers Weyers et al., (1993) -SHRP
Service life for penetrating sealer (years) 5 to 7
Sherman et al., (1993)-Texas DOT
5
Zemajtis and Weyers, -Virginia Tech. (1996)
7
NYSDOT (1997)
4
Meggers (1998)- Kansas DOT
8 to 11
Soriano (2002) – South Dakota DOT
4 -10
Sohanghpurwala (2006) – NCHRP 558
5 to 7
Mamaghani (2007) – North Dakota DOT
5
Wenzlic (2007) – Missouri DOT
3 to 10
Filice wt al., (2008) – Alberta DOT
4
Kraus et al., (2009) -NCHRP 20-07
5 to 10
Morse (2009)- Illinois DOT
4 to 5
Researchers
Bridge washing data Bridge Washing frequency relative to bridge element need in the US (Burgdorfer)
Reduction of chloride, nitrates, sulfates by washing (Johnson and James 2001) Pre wash (µg/cm2) Chlorides Nitrates Sulfates Total Salt
33 13 10 56
Water Wash (µg/cm2) 20 8 4 32
Salt Remover Wash (µg/cm2) 8 2 2 13
Bridge Washing Prioritization Table • Portion of bridge washing prioritization table • Weathering steel with joints, steel with coating, jointless weathering steel, longer-span concrete
No.
Bridge Federal ID
Design No.
Year built
# of Span
Superstructure Material
Wearing Surface
Recent Deck CS Rating
Recent Superstructure CS Rating
1 2 3 4 5 6 7 8 9 10 11 12 13
15435 33540 15417 15423 15425 33735* 32428 34784 15426 30593 15413 15427 31461
930022 930005 930011 930014 930015 930037 930034 930040 930016 930003 930009 930017 930032
1986 2009 1960 1935 1920 2009 2009 2014 1928 2004 1987 1925 2005
3 3 1 1 2 3 3 4 4 3 3 3 3
Steel Steel Steel Steel Steel Steel Steel PrestConc PrestConc PrestConc PrestConc PrestConc P tC
Asphalt NotApplic Asphalt PlainConc NotApplic PlainConc PlainConc NotApplic Asphalt PlainConc Asphalt Asphalt Pl i C
7 8 6 7 5 9 8 9 7 8 8 7 7
7 9 3 5 5 9 8 9 7 9 7 7 9
Agenda • Introduction to Columbia, MO • Challenges for a small city • Design of preservation program – Information sources – Bridge preservation inspection program – Short term and long term activities – Selection rationale
• Conclusion
City of Columbia, MO • Fourth largest city in Missouri – 120,000 people – 35,000 students at the University of Missouri
• Educational center – University of Missouri • • • • •
Law Engineering Medical Veterinary Medicine Life sciences
– Stephens College – Columbia College
City Department of Public Works • • • • • • • • • • •
Engineering Maintain sidewalks Mowing Maintaining signage Storm response Maintain bridges New bridge construction Rehab and repair Pavements Etc….. Resources are limited
Challenges for a small city • Staffing is limited and responsibility is very diversified • Community relations and response are a major activity – Overseeing a bridge repair in the morning – Fixing a pothole in a neighborhood in the afternoon
• Worst-first approach • How can we reduce the number of repair / rehabs for our bridges • Push-off major repairs to preserve limiting funding – With limited staff and resources
• Practical and implementable with current staffing
5
Bridges in the City of Columbia, MO
Bridge population in Columbia, MO • 38 bridges and culverts in the city – 29 bridges and 9 culverts
• Average age of 32 years – 1/3 of the bridges are less than 15 years old – Almost 50% of the bridge decks are rated 7 or higher
Bridges with issues….
Unusual bridges….
New bridges with good durability characteristics
Goal of the Project Extend service life of the local bridges in Columbia, MO
Objective of the Project Develop guidelines for bridge maintenance and preservation focused on practical and implementable technologies and procedures such as; • Bridge deck flushing • Fog and seal program • Crack sealers
Bridge Preservation ..actions or strategies that prevent, delay, or reduce deterioration of bridge elements; restore the function of existing bridges; keep bridges in good condition; and extend their useful life. Preservation actions may be preventative or condition-driven.” Maintaining a bridge in good condition can extend the service life of the bridge and has proven to be cost effective as compared with allowing bridge to deteriorate, leading to more extensive and costly repairs.
Preservation Classification Schematic diagram of bridge preservation activities
Typical bridge preservation activities • Focus: preventing or slowing corrosion damage • Moisture and chlorides
Bridge Component All
Deck
Superstructure
Substructure
Description Sweeping, power washing or flushing Deck washing Deck sweeping Drainage cleaning / repair Joint Cleaning Deck sealing Crack sealing Deck Patching Asphalt Overlay with membrane Joint seal replacement Drainage repair Bridge approach restoration Seat and beam end washing Spot or Zone painting Debris removal Scour counter measures Clearing debris
Preventative Maintenance Type
Action Frequency (yrs) 1-2
Cyclical
1 1 1 1 7-10 4-5 1-2
Condition Based
12-15 10 1
Cyclical
Condition based Condition based
2 2 As needed As needed As needed
• We have heard about preservation, but how do we decide which preservation actions to take, and when? – Which bridges, when – What are short term actions and longer terms actions that are appropriate and practical for the city?
INFORMATION SOURCES FOR PUBLIC WORKS • MoDOT performs NBIS inspections for the state – Notes sections contain preservation and maintenance activities
• Inspection of bridges – Staffing is limited and responsibilities are diversified – Engineer covers all aspect of the roadways, from pavements to cutting vegetation, developing new projects, and construction project oversite
Bridge Preservation Inspection Program (BPIP) • Bridge Preservation Inspection Program – Used to identify condition-based preservation needs – Limited training required – Simple guidelines that can be executed by summer interns • MU students
• A typical inspection could be completed in one hour or less • Is low cost and assist maintenance personnel with identifying where PM activities may be required • BPIP provides additional data on the current needs in the inventory in a practical, low-cost manner
Bridge Preservation Inspection Program BPIP
Vegetation on Bridge ID # 0930009
Visual guide for bridge preservation 1
Question Are there any unsealed cracks in the surface of the deck? Y/N Notes
2
Are there any spalls in the bridge deck that require patching? Y/N Notes
3
Is there debris on the surface of the deck? Y/N Notes
Photograph of Typical Condition
Visual guide for preservation inspection • Photos gather from city of Columbia bridges
20
Current Preservation Needs • Field visits to bridges and culverts yielded a list of current actions
Recommendations • Focus on low-cost activities to prevent deterioration and keep good bridges in good condition • Identify and prioritize PM activities such as cleaning and washing bridges to extend service life • Include a mix of short term, mid-term and long-term PM activities • Recommendations developed based on analysis – Crack sealing – Bridge cleaning – Bridge washing – Deck sealing – Superstructure washing – Clear vegetation – Repair leaking joints
Schedule for Preventative Maintenance • PM activities were prioritized based on – A subjective risk analysis considered the PM activity potential impact, cost, and ease of implementation – Cost was rated as low, medium or high – Impact estimated based on the available literature and engineering judgement – Ease of implementation considered if the activity could be completed by maintenance personnel or temporary workers, or require a contract
Schedule for Preventative Maintenance • Prioritized for impact, cost, ease of implementation Scenario
Seal cracks in bare concrete decks
Clean Decks and drains
Priority
ASAP
12 months
Clean beam seat areas of debris
12 months
Implement bridge deck washing / flushing program
24 months
Rationale Open cracks in the surface of a bridge deck are the most direct pathway for moisture and chlorides to penetrate to reinforcing steel and cause corrosion damage. The sealing of cracks with have an immediate, positive effect on reducing the deterioration of bridges. The activity can be completed with existing maintenance personnel. Sweeping and cleaning of bridge decks will immediately have an effect on reducing the rate of corrosion by removing moisture trapped against the materials. The activity can be completed with existing maintenance personnel or temporary staffing. Clearing beam seats of debris will immediately have an effect on reducing the rate of corrosion by removing moisture trapped against the materials. The activity can be completed with existing maintenance personnel or temporary staffing. Deck washing will have a long-term benefit of reducing the rate of corrosion in bridge elements. The impact of deck washing may be less than impact of simply removing debris from the surface, and the cost is higher.
Selection Criteria BPIP / Inspection results
BPIP / Inspection results BPIP / Inspection results
All bridge decks.
Scenario
Priority
Implement bridge superstructure washing
24 months
Implement a bridge deck sealing program.
24 months
Clear vegetation
Repair leaking joints
36 months
48 months
Rationale Superstructure washing will have a long-term benefit of reducing the rate of corrosion in bridge elements. The impact of superstructure washing is less than the impact of simply removing debris from the surface, and the cost is higher. Access to the areas of the bridge that require washing is also more difficult, and pressure washing is required. Sealing of concrete decks will extend the service life of the deck and have a positive long term effect on the deterioration rate of the deck. However, the costs are higher than other activities, and this may require contract forces to complete the work. Maintenance personal can seal decks with some modest training and procedures. Removing vegetation surrounding or growing onto bridges will diminish the corrosive environment by improving air flow through the structure and not trapping moisture against the surface of the concrete. However, the impact of this activity is much smaller as compared with removing debris or washing bridge elements. Costs are low and maintenance personnel or temporary workers can complete this task. Repairing leaking joints in bridges will reduce deterioration at the beam-ends by preventing water and chlorides from draining directly onto these elements. This will have a impact of extending the service life of the bridge. Requirements depend on the type of joints. Replacing leaking deck seals has a higher cost relative to other PM activities.
Selection Criteria Prioritize steel bridges and bridges with open or leaking joints
See Table 4
BPIP / Inspection results
BPIP / Inspection results
Bridge Cleaning • Includes bridge deck, drainage, and support bearing • Remove debris accumulation to prevent corrosion damage • Lowest cost action
Bridge Washing • Clean/remove debris from decks and beam seats prior to washing • Washing bridge elements with water to remove debris – Pressurized water for superstructure and drainage area – Flooding or pressurized water for the deck
Bridge Superstructure Washing Prioritization • • • • •
For most bridges, bridge washing should focus on the beams ends, bearing and beam seats Surrounding the drains be considered for washing Bridges with leaking joints be prioritized over bridges with sound joints Jointless bridges may not require periodic washing Weathering steel bridges will benefit significantly
Example – Bridge Cleaning and Washing 930022
Example 930022 – replace seal
Crack Sealing • • • • •
Done by crack chasing Includes high molecular methacrylate (HMWM) and other polymers Effective for crack spacing of 2 ft. or greater Lifespan is less than penetrating sealers Reapplication frequency of 3 to 5 years
Which decks should be sealed? • Decks currently in good condition with concrete decks No.
Bridge Federal ID
Design No.
Year built
# of Spans
Deck Type
Wearing Surface
1 2 3 4 5 6 7 8 9 10 11 12 13 14
30593 32732 15429 15437 28793 31461 34416 34784 33734 15423 32428 34415 33540 33735
0930003 0930010 0930018 0930024 0930031 0930032 0930039 0930040 0930036 0930014 0930034 0930038 0930005 0930037
2004 2009 1982 1990 1982 2005 2012 2014 2009 1935 2009 2012 2009 2009
3 2 2 2 1 3 3 4 3 1 3 3 3 3
ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc ReinConc
PlainConc PlainConc PlainConc PlainConc PlainConc PlainConc PlainConc NotApplic PlainConc PlainConc PlainConc NotApplic NotApplic PlainConc
Recent Deck CS Rating 8 7 7 7 7 7 8 9 8 7 8 7 8 9
Bridge Condition Data • Data-driven PM activities provide increased efficiency by completing condition related activities • MoDOT biennial safety inspection report contains inspector recommendations for maintenance and repair • Recommendations are important inputs to identify condition-related activities – Deck sealing, clearing vegetation and bank protection
MoDOT Preservation Recommendations No.
Bridge Federal ID
Design No.
Inspection Date
1
15392
0930001
04/14/2015
2
15400
0930002
04/23/2015
3
30593
0930003
04/23/2015
4
15409
0930006
4/23/2015
5
15413
0930009
4/23/2015
6 7 8 9
15422 32732 15426 15427
0930013 0930010 0930016 0930017
4/27/2015 4/27/2015 4/23/2015 4/27/2015
10
15429
0930018
4/23/2015
Work Comment
Place bank protection along the north abutment and bank. Repair the deck. Repair the driving surface, waterproof, and place an asphalt wearing surface on the deck. Place rock along the north abutment. Consider replacing the superstructure. Hydrodemolition candidate. Repair the deck and replace the wearing surface. Seal the edge of the deck and beams. Clean out the deck scuppers. Consider replacing the wearing surface. Consider sealing the deck with silane. Replace the wearing surface. Repair the north bank protection Consider sealing the deck with silane and painting the deck edges with an epoxy paint.
Conclusions • Maintaining bridges in good condition can extend the life of a bridge and forestall maintenance, repair and replacement needs • Cost effective as compared with allowing bridge to deteriorate, leading to more costly repairs • Specific recommendations and prioritization for a preservation PM program for bridges in Columbia • Implementation will help the city keep its network of 38 bridges and culverts in good condition using limited resources and meet future needs
Thank you! Questions
MIZ…
MoDOT PM EPG • MoDOT engineering policy guidance for PM activities Preservation Action Superstructure Washing Deck Flushing/Washing Vegetation Control Debris Removal Drainage System Cleanout/repair Spot Painting Deck Sealing Seal concrete cracks
Seal Joints Seal HMA cracks
MoDOT Eng. Guide 771.2 Bridge Cleaning and Flushing 771.2 Bridge Cleaning and Flushing 771.20 Cut and Spray Brush and Vines 771.8 Remove Drift 771.2 Bridge Cleaning and Flushing 771.4 Drain Basin Maintenance 771.14 Spot Painting of Bearings and Piling 771.16 Penetrating Concrete Sealer – Silane 771.17 Concrete Crack Filler - Low Viscosity Polymer (LVP) 771.18 In-Deck Bridge Deck Crack Filler 771.19 Chip Seal to Entire Deck (R322 Bridge Seal Coats Maintenance Planning Guidelines) 771.10 Bridge Joint Sealing - Hot Pour 771.11 Bridge Joint Sealing – Silicone 771.12 Bridge Joint Sealing - Polytite 413.5 Crack Treatment in Bituminous Pavements
Project Activities • Literature search • Contacts within the preservation community – Interviews with state-level bridge owners – Participate in the Midwest Bridge Preservation Partnership
• Field survey of several City of Columbia bridges – Evaluation of City of Columbia needs
• Subjective risk analysis for preventative maintenance (PM) prioritization
Periodic PM activities • Some PM actions need to be repeated over the long term at different intervals. Time Period Short Term (1224 months)
Mid-Term (2572 months)
Long Term (73120 months)
PM Action
Expected Service Life (yrs)
Bridge Selection Criteria
Seal concrete cracks Drainage System Cleanout/repair Deck cleaning and washing
3-5 1
Decks with cracking All bridge decks with drains
1
Clean and wash bridge beam ends, beam seats and bearings Deck Sealing Seal HMA cracks
1-2 10 3-5
All bridges will benefit from cleaning and washing Bridges with accumulated debris and leaking joints; prioritized as noted above Bare concrete decks in good condition Asphalt decks with cracking
Seal Joints Spot Painting Reseal cracks after 3-5 years.
7-10 7 3-5
Based on inspection results Bridges with damage at the beam ends Cyclical
Reseal decks after 7 to10 years
Penetrating Sealers • Reducing concrete diffusivity and sealing small cracks to reduce capillary actions • Applied after 3 to 6 months after construction • Periodic reapplication necessary 7 to 10 yrs • Includes silanes, siloxenes, siliconates, silicones, and linseed oil • Seal tight crack 0.010 in wide or less
Penetrating Sealers and Crack Sealing • MoDOT deck sealing recommendation (EPG 771.15) New Decks and Decks with minimal cracking Decks with hairline cracks < 1/128” (0.008 in.) wide Decks with cracks >1/128” (0.008 in.) wide Decks with cracks >1/64” (0.016 in.) wide
EPG 771.16 Penetrating Concrete Sealer - Silane EPG 771.17 Concrete Crack Filler -Low Viscosity Polymer (LVP) EPG 771.18 In-Deck Bridge Deck Crack Filler EPG 771.19 Chip Seal to Entire Deck
• Service life of penetrating sealers found by different researchers Weyers et al., (1993) -SHRP
Service life for penetrating sealer (years) 5 to 7
Sherman et al., (1993)-Texas DOT
5
Zemajtis and Weyers, -Virginia Tech. (1996)
7
NYSDOT (1997)
4
Meggers (1998)- Kansas DOT
8 to 11
Soriano (2002) – South Dakota DOT
4 -10
Sohanghpurwala (2006) – NCHRP 558
5 to 7
Mamaghani (2007) – North Dakota DOT
5
Wenzlic (2007) – Missouri DOT
3 to 10
Filice wt al., (2008) – Alberta DOT
4
Kraus et al., (2009) -NCHRP 20-07
5 to 10
Morse (2009)- Illinois DOT
4 to 5
Researchers
Bridge washing data Bridge Washing frequency relative to bridge element need in the US (Burgdorfer)
Reduction of chloride, nitrates, sulfates by washing (Johnson and James 2001) Pre wash (µg/cm2) Chlorides Nitrates Sulfates Total Salt
33 13 10 56
Water Wash (µg/cm2) 20 8 4 32
Salt Remover Wash (µg/cm2) 8 2 2 13
Bridge Washing Prioritization Table • Portion of bridge washing prioritization table • Weathering steel with joints, steel with coating, jointless weathering steel, longer-span concrete
No.
Bridge Federal ID
Design No.
Year built
# of Span
Superstructure Material
Wearing Surface
Recent Deck CS Rating
Recent Superstructure CS Rating
1 2 3 4 5 6 7 8 9 10 11 12 13
15435 33540 15417 15423 15425 33735* 32428 34784 15426 30593 15413 15427 31461
930022 930005 930011 930014 930015 930037 930034 930040 930016 930003 930009 930017 930032
1986 2009 1960 1935 1920 2009 2009 2014 1928 2004 1987 1925 2005
3 3 1 1 2 3 3 4 4 3 3 3 3
Steel Steel Steel Steel Steel Steel Steel PrestConc PrestConc PrestConc PrestConc PrestConc P tC
Asphalt NotApplic Asphalt PlainConc NotApplic PlainConc PlainConc NotApplic Asphalt PlainConc Asphalt Asphalt Pl i C
7 8 6 7 5 9 8 9 7 8 8 7 7
7 9 3 5 5 9 8 9 7 9 7 7 9
