Historic Bridge Management Plan Inspection and Maintenance Plan MnDOT Bridge No. 5151 Over the Redwood River Marshall, Lyon County

Report prepared for

Minnesota Department of Transportation

Report Prepared by

Greg Mathis, Project Historian and

James Stoutland, District Bridge Engineer

July 2014

Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

TABLE OF CONTENTS 1.0

INTRODUCTION ............................................................................................................................... 1

2.0

RECOMMENDED INSPECTIONS FOLLOWING THE 2013 REHABILITATION ........................... 11

3.0

RECOMMENDED MAINTENANCE ACTIVITIES FOLLOWING THE 2013 REHABILITATION .... 13

4.0

PROJECTED COSTS FOR MAINTENANCE ................................................................................. 16

5.0

REFERENCE LIST ......................................................................................................................... 17

APPENDIX A: COST DETAILS................................................................................................................... 19 APPENDIX B: SPECIFICATIONS FOR MAINTENANCE AND REPAIR MATERIALS .............................. 23 APPENDIX C: CONCRETE REPAIR AND STAIN APPLICATION PROCEDURES .................................. 29

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

LIST OF FIGURES Figure 1. North Elevation, Facing Southeast ................................................................................................ 6 Figure 2. North Elevation and Railing, Facing East-Southeast..................................................................... 6 Figure 3. Bridge Deck, Facing East .............................................................................................................. 7 Figure 4. South Elevation and Railing, Facing East ..................................................................................... 7 Figure 5. Southwest Wingwall and Railing, Facing North ............................................................................. 8 Figure 6. South Elevation, Facing Northeast ................................................................................................ 8 Figure 7. Substructure and Superstructure (South Elevation), Facing Northwest ........................................ 9 Figure 8. Bridge Deck, Facing West ............................................................................................................. 9 Figure 9. North Railing and Lights, Facing Northwest ................................................................................ 10 Figure 10. Plan for Lights with Union Metal Part Numbers for Castings .................................................... 27 Figure 11. Spalled Area with Aggregate in Original Concrete Exposed ..................................................... 31 Figure 12. Aggregate Rubbed Into Surface of New Concrete .................................................................... 32 Figure 13. Concrete Stain Sample Panels .................................................................................................. 33 Figure 14. Applying Concrete Stain ............................................................................................................ 33 Figure 15. Staining Completed ................................................................................................................... 34 Figure 16. Concrete Repair to Railing Post ................................................................................................ 35 Figure 17. Concrete Repair to Railing Post ................................................................................................ 36 Figure 18. Spraying Water on Concrete Repairs to Add Texture to Simulate Weathered Concrete .......... 36 Figure 19. Acid Washing to Lighten the Stain and Blend with Original Concrete ....................................... 37 Figure 20. Charcoal Wash Immediately After Application .......................................................................... 37

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Bridge No. 5151

Introduction

In May 2013, the Minnesota Department of Transportation (MnDOT) let a contract for the rehabilitation of Bridge No. 5151. The rehabilitation was based on recommendations for the bridge contained within the historic bridge management plan (HBMP) prepared by Mead & Hunt and HNTB on behalf of MnDOT in June 2006, and in accordance with Secretary of the Interior’s Standards for the Treatment of Historic Properties and the National Park Service’s Preservation Brief 15: Preservation of Historic Concrete. Construction documents were prepared by Olson & Nesvold Engineers, P.S.C. (ONE) with technical assistance from The 106 Group Ltd. (106 Group) on matters related to historic preservation. Construction began in May 2013, structural work was completed in late July, and the project was finished in July 2014. July 2014. The expected service life for the rehabilitation is approximately 10 years for the railing posts and 30 years for the rest of the structure. If in the future the railing posts are treated with silane as described in Section 3.0, their service life could be extended to 30 years. The following Inspection and Maintenance Plan (IMP) is based on the 2013 rehabilitation and supersedes the inspection and maintenance plans, schedules, and cost estimates included in the 2006 HBMP. The purpose of the IMP is to serve as a guide on how to properly inspect and maintain the rehabilitated bridge to ensure its long-term preservation. The recommendations contained within this plan are based on MnDOT’s Bridge Inspection Field Manual, Version 1.9, MnDOT Engineering Services Division Technical Memorandum No. 11-06-B-03, the Secretary of the Interior’s Standards for the Treatment of Historic Properties (SOI Standards), the Management Plan for Historic Bridges in Minnesota, and National Park Service’s Preservation Brief 15: Preservation of Historic Concrete. Background Historic Bridges in Minnesota MnDOT completed a statewide inventory and evaluation of bridges in Minnesota constructed before 1956, which resulted in the development of a list of pre-1956 bridges owned by MnDOT and local governments that were eligible for the National Register of Historic Places (NRHP). Bridge No. 5151 was one of the bridges included on the list because it had been placed on the NRHP in 1998. In June 2006, a statewide HBMP was prepared and individual management plans were completed for 23 of 24 stateowned bridges selected for preservation, including Bridge No. 5151. In 2008, the Federal Highway Administration (FHWA); the Advisory Council on Historic Preservation; the United States Army Corps of Engineers, St. Paul District; the Minnesota State Historic Preservation Office (SHPO); and MnDOT entered into a programmatic agreement (PA) concerning pre-1956 historic bridges in Minnesota. Among the stipulations of this agreement, NRHP nominations were required to be prepared for all National Register eligible state-owned pre-1956 bridges. The PA also stipulated the preservation of the 24 pre-1956 bridges identified for preservation in 2006 in accordance with the SOI Standards. Bridge No. 5151 Bridge No. 5151 was built in 1931 to carry vehicular traffic on Trunk Highway (TH) 14 (now TH 19) over the Redwood River just southwest of downtown Marshall in Lyon County. The bridge has a two-span cast-in-place concrete T-girder type design with box-type abutments and Classical Revival detailing. It

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

has an out-to-out length of 101’ 0” (101’ 8” over the deck coping), an out-to-out width of 55’ 8” inches (58’ 2” over the deck coping at the end posts), and a 52’ 0” wide deck, including the sidewalks. The substructure includes two reinforced-concrete abutments with concrete-slab approach panels, and a reinforced-concrete pier. Architectural details on the substructure include curved concrete floor beam ends, rounded piers and abutments, and recessed abutment panels. The superstructure consists of two 32’ 3” long spans, each comprised of eight girders that carry a concrete deck with a concrete wearing course. The bridge carries two traffic lanes, one in each direction, with sidewalks along both sides of the roadway. The bridge features an open balustrade. The railing has ornamental concrete posts with a recessed panel on the inner and outer faces, and steel, Wisconsin type railing with tubular top and bottom rails and square pickets. There are two Classical Revival light standards on each side of the bridge, mounted on intermediate railing posts. Cast bronze bridge plates are located on the southwest and northeast railing endposts that read “Minnesota Highway Department Bridge No. 5151 1931.” Bridge No. 5151 was added to the NRHP on June 29, 1998. The bridge is significant under Criterion C, in the area of engineering, within the historic context “Reinforced-Concrete Highway Bridges in Minnesota, 1900-1945” for its aesthetics. Bridge No. 5151 is a rare surviving example of a bridge with good integrity that was designed based on a general plan developed by the highway department in the late 1920s for urban trunk highway bridges. Originally planned as an unornamented, utilitarian, reinforced-concrete girder span, City officials were so impressed with the design of companion Bridge No. 5083 that they requested the Minnesota Highway Department apply the same aesthetic treatment to Bridge No. 5151. The aesthetic treatment of Bridge No. 5151 includes the ornamental metal Wisconsin Type railing, Classical Revival light standards, and concrete posts with recessed panels. The reinforced concrete substructure also has architectural details, including curved concrete floor beam ends, rounded piers and abutments, and recessed abutment panels that contribute to the design of the structure. Another character-defining feature is the park setting in which the bridge is located. The wooded and landscaped grounds and nearby ballpark compliment the ornamental design of Bridge No. 5151 in a manner similar to that of nearby Bridge No. 5083, which is located on the new route of TH 14 (later renumbered TH 19) through the city of Marshall (Hess 1997). Since Bridge No. 5151 was listed on the NRHP, an engineer and historian inspected it in September 2005, and a prepared a HBMP for it in June 2006. The HBMP assessed the condition of the bridge as follows: Serviceability Observations: The load rating calculations from 1975 indicate that the values provided in the inventory are based on checking flexure at the middle of the beam spans. Conversations with the Bridge Office indicate that similar bridges have been controlled by shear capacity. The sidewalk is undermined and has settled on the approach to the northeast corner of the bridge, generating a tripping hazard. Sand and vegetation below span 1 are partially blocking the hydraulic opening. The stream was entirely below span 2 during the site visit.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Structural Condition Observations: Based on available information, the bottoms of the abutment slab spans are inaccessible, have not been inspected, and their condition is unknown. Both abutment slab spans have sealed cracks and patched regions. The lower rail of the metal railing has complete section loss in one section of one panel on the southwest corner of the bridge. Non-Structural Observations: The globes atop the light standards differ from those detailed in the original plan set. A utility line is located very close to the top of the northeast light standard. Historically appropriate replacement globes could conflict with the line. The diversion channel is believed to have reduced the normal flows of the Redwood River through Marshall. The reduced flows have lead to reduced velocities and increased sedimentation (Mead & Hunt and HNTB 2006a). Based on the overall conditions of the bridge, the HBMP recommended rehabilitating Bridge No. 5151 for continued vehicular use. The plan recommended both immediate stabilization activities and longer-term preservation activities: Recommended Stabilization Activities: 1. Repair the undermined sidewalk on the approach to the northeast corner of the bridge. 2. Repair the lower rail on the metal railing. Remove the deteriorated railing panel. Remove sufficient bottom rail to reach sound steel capable of being butt-welded. Weld in place replacement 3-inch diameter steel pipe. Prime and paint repaired areas. Reinstall the railing panel/attaching the panel to the concrete posts with four rail sockets. 3. Determine if the silt deposits compromise the hydraulic performance of the river in the vicinity of the bridge. If they do, remove the vegetation and silt deposits from below the bridge and profile the channel with rip rap or other measures to ensure that proper water velocities are maintained at a variety of flows. Recommended Preservation Activities: 1. Perform a comprehensive load rating analysis. At a minimum, the analysis should consider both the abutment slab spans and the beam spans evaluating both shear and flexure capacities. 2. Conduct a concrete testing program to determine the extent and location of spalls, cracking, delamination, or other types of deterioration. Chloride sampling

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

and coring may be utilized to determine the characteristics of in-place concrete and the amount of chloride contamination. Complete any electrochemical chloride extraction indicated by the testing prior to repair of concrete components. 3. Mill and overlay the beam spans and the slab spans. 4. Mill and overlay the sidewalks. 5. Following any electrochemical chloride extraction, rehabilitate the deteriorated concrete fascia and wingwall components. Use standard Mn/DOT repair methods and the National Park Service’s “Preservation Brief No. 15, Preservation of Historic Concrete.” Consult with Mn/DOT’s Office of Bridges and Structures before final determination of the means and methods of concrete repairs. Apply Mn/DOT special surface finish to exposed concrete subsequent to the repairs. Apply anti-graffiti coating to appropriate areas (Mead & Hunt and HNTB 2006a). Pursuant to recommendations in the HBMP, several stabilization projects were completed. The undermined sidewalk on the approach to the northeast corner of the bridge was repaired in 2006. In 2008, the lower rails on the railing panels were repaired and the railing panels repainted in 2008. As part of this project, new anchors were installed in the railing posts. The new anchors were offset to the side and in a higher location than the original anchors. 2013 Rehabilitation Pursuant to the HBMP, the SOI Standards, and Preservation Brief 15, MnDOT completed a rehabilitation of Bridge No. 5151 during the 2013 construction season (see Figures 1-9 for images of the completed rehabilitation). The MnDOT Cultural Resources Unit (CRU) found that the rehabilitation approach met the SOI Standards and would have no adverse effect on Bridge 5151. The SHPO concurred with this finding. The rehabilitation included: Superstructure: 1. Milling 1” of concrete off each of the sidewalk surface areas of the main spans and replacing it with a nominal 1½” overlay. 2. Scarifying 3” of concrete off the main span deck surface areas 3. Removing unsound concrete from the deck after scarifying and repairing it with new concrete. 4. Reconstructing one deck drain in a main span. 5. Removing and replacing the abutment roadway slabs and sidewalks. 6. Reconstructing the paving bracket at each end of bridge. 7. Removing and replacing portions of the end diaphragms and end portions of the deck of the main spans.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

8. Reconstructing the sidewalk curb on the main spans. 9. Placing a 2” concrete wearing course on the new abutment roadway slabs, and a 3” concrete wearing course on the repaired main span roadway. 10. Repairing unsound areas of the concrete rail posts a. Staining repairs. 11. Salvaging, repairing, galvanizing, painting, and reinstalling the historic metal railing. a. Installing new anchorage for the metal railing. 12. Reconstructing the historic roadway lighting system. a. Salvaging, repairing, painting, and reinstalling the historic light standards on the north side of the bridge. b. Installing replica light standards on south side of bridge. Substructure: 1. Removing and replacing tops of concrete abutment wingwalls. 2. Removing and repairing unsound concrete on the abutments and pier. 3. Sealing cracks in the abutments and pier. 4. Staining newly placed concrete.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 1. North Elevation, Facing Southeast

Figure 2. North Elevation and Railing, Facing East-Southeast

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 3. Bridge Deck, Facing East

Figure 4. South Elevation and Railing, Facing East

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 5. Southwest Wingwall and Railing, Facing North

Figure 6. South Elevation, Facing Northeast

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 7. Substructure and Superstructure (South Elevation), Facing Northwest

Figure 8. Bridge Deck, Facing West

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 9. North Railing and Lights, Facing Northwest

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

2.0

Bridge No. 5151

Recommended Inspections Following the 2013 Rehabilitation

Bridge No. 5151 was rehabilitated in 2013. Construction began in May, structural work was completed in th late July, and the bridge reopened to traffic on July 27 . The rehabilitation was fully completed in July 2014. Post rehabilitation, the following inspections should be performed to monitor the condition of Bridge No. 5151 starting in 2014. Inspections shall be performed in accordance with current MnDOT requirements found in this plan and the most recent version of the Bridge Inspection Field Manual. Who Should Conduct the Inspections? Prior to conducting the inspection, the Bridge Inspection Team Leader (BITL) shall review the 2006 HBMP and this update to become familiar with the significance of the bridge and its character defining features. After completing the inspection report, and prior to considering work tasks on historically significant features, the District shall consult with CRU. The goal of this consultation shall be to ensure that the issues identified during the inspection that may affect the long-term preservation of the structure and its historically significant features are given proper consideration during the planning of repairs. Inspections Inspections should be performed in accordance with MnDOT standards as described in the most current versions of Bridge Inspection Field Manual. The following schedule should begin based on a substantial project completion date of August 1, 2013. Routine: 1. Conduct an initial inspection within 1 year of the date that the bridge was reopened to traffic after the 2013 rehabilitation. 2. Conduct subsequent routine inspections at 2-year intervals. a. Conduct in-depth inspection of railing posts for new or accelerated deterioration. 3. If underwater elements of the bridge cannot be visibly evaluated during periods of low flow or by feel for condition, integrity and safe load capacity, due to excessive water depth and turbidity, conduct an underwater inspection at 5-year intervals. 4. As needed, conduct in-depth inspections as required per FHWA guidelines to identify deficiencies not readily detectable using routine inspection procedures. Special: 1. As the 2013 rehabilitation addressed all major structural issues, no special inspections are anticipated. However, should any structural issues develop during the current life cycle, monitor during routine and in-depth inspections as indicated by fatigue life assessment. In the event that a critical deficiency or hazardous deficiency is discovered during an inspection, the Bridge Inspector shall immediately notify the MnDOT District Bridge Engineer. Upon receiving notification, the MnDOT District Bridge Engineer shall consult with the MnDOT Bridge Office to prepare a strategy for corrective action to resolve the deficiency. As part of this effort, the District

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Bridge Engineer and Bridge Office shall consult with the MnDOT CRU prepare a strategy for addressing deficiencies that do not post an imminent life safety threat. 2. Inspect piers and abutments for scour damage after flood events.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Bridge No. 5151

Recommended Maintenance Activities Following the 2013 Rehabilitation

Subsequent to the rehabilitation that was substantially completed in August 2013, and fully completed in July 2014, the following maintenance activities should be performed on Bridge No, 5151, Preventive Maintenance Annually 1. Power wash (low pressure) and flush railings, drainage system, deck cracks, joints, bridge seats, fascia beams, abutment ends, abutment wingwalls, and pier ends with water, preferably in the spring. Every 5 Years 1. Seal any cracks in original concrete by injection with matte finish caulk that, when cured, matches the color of the concrete (see Appendix B for material specifications). 2. Spot paint steel railing panels and light standards (see Appendix B for material specifications). 3. Seal cracks in concrete wearing course, sidewalks, and curbs (non-historic concrete). Every 7 Years 1. Seal concrete deck surfaces (wearing course, sidewalks, and curbs). Flood seal full deck surface, approach panels, and sidewalk. Care shall be taken to avoid placing sealant on any historic concrete or character defining features, such as the railing posts or deck fascia. Every 8 years 1. Seal the poured deck joint seals. Potential Additional Preventive Maintenance The 2014 rehabilitation did not address high chloride levels in the concrete railing posts. Since filmforming coatings were determined not to meet the SOI Standards, at the time this management plan was completed, the MnDOT Office of Materials and Road Research Service (OMRRS) was conducting testing of several silane products for possible use on the railing posts. After the OMRRS testing is completed, OMRRS and the District Bridge Engineer shall consult with the CRU and SHPO to determine if a silane product will provide long-term protection for the concrete railing posts, without adversely affecting the historic material and meet the SOI Standards. If it is determined that a silane product meets the SOI Standards, it can be applied to the railing posts following manufacturer recommendations. 1. If silane is applied to seal the concrete railing posts, it should be reapplied every seven years. 2. If silane is not applied, see Rehabilitation Maintenance section below for further guidance.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Reactive Maintenance High Priority (to be completed within 0 to 1 year of observation) 1. Debris removal, erosion repair and protection, and clean up due to flood events. Assume a 5-year cycle. 2. Repair scour damage to substructure units. 3. Repair damage caused by vehicular accidents. 4. Repair spalling of railing post surfaces (see Appendix C for concrete repair and staining procedures and Appendix B for material specifications and colors). 5. Repair deep spalls in bridge deck. Medium Priority (to be completed within 1 to 3 years of observation) 1. Repair small spalls or delaminations in the driving lanes. 2. Repair minor erosion around the abutments and wingwalls. 3. If needed at intervals less than 5 year, seal large crack in the northeast endpost with matte finish caulk that, when cured, matches the color of the concrete (see Appendix B for material specifications). 4. Repair damage to globes. 5. Replace LEDs at end of life cycle (see Appendix B for material specifications). 6. Repair damage/deterioration to bridge lighting electrical system. Low Priority (to be completed within 3 or more years of observation) 1. Touch up faux finish on globes (see Appendix B for material specifications). 2. Repair non-structural spalling or deterioration of pier, abutment, wingwalls, or curb surfaces (see Appendix C for concrete repair and staining procedures and Appendix B for material specifications and colors). 3. Remove excessive brush growth on embankments adjacent to abutment wingwalls. Rehabilitation Maintenance (Long-term and major work, typically to be done by contract) Every 20 Years 1. Repair steel railing panels and complete paint system at fabrication shop in accordance with MnDOT Standard Specifications (see Appendix B for material specifications and color).

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

2. Repair light standards, install new gaskets, and complete paint system at fabrication shop, in accordance with MnDOT Standard Specifications (see Appendix B for material specifications and color). 3. Clean and reapply faux finish to globes (see Appendix B for material specifications and color). 4. Repair railing posts if silane treatment is not applied (see Appendix C for concrete repair and staining procedures and Appendix B for material specifications and colors). Every 25 Years 1. Remove and replace the wearing course, including deck repairs.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Bridge No. 5151

Projected Costs for Maintenance

Appendix A presents the maintenance schedule for Bridge No. 5151. The schedule includes activities and costs associated with maintenance activities and repair work.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Bridge No. 5151

Reference List

Gaudette, Paul, and Deborah Slaton 2007 Preservation of Historic Concrete. Preservation Brief 15. National Park Service, Washington, DC. Hess, Jeffery A. 1997 “Bridge No. 5151,” National Register of Historic Places Registration Form. On file Minnesota State Historic Preservation Office, St. Paul, Minnesota. Mead & Hunt and HTNB 2006a Minnesota Department of Transportation (Mn/DOT) Historic Bridge Management Plan: Bridge Number 5151. On file Minnesota Department of Transportation, St. Paul, Minnesota. 2006b Management Plan for Historic Bridges in Minnesota. On file Minnesota Department of Transportation, St. Paul, Minnesota. Minnesota Department of Transportation 2011a Bridge Inspection Field Manual, Version 1.9. Minnesota Department of Transportation Bridge Office, Oakdale, Minnesota. 2011b Minnesota Department of Transportation, Engineering Services Division Technical Memorandum No. 11-06-B-03. On file Minnesota Department of Transportation, St. Paul, Minnesota. Weeks, Kay D., and Anne E. Grimmer 1995 The Secretary of the Interior’s Standards for the Treatment of Historic Properties: With Guidelines for Preserving, Rehabilitating, Restoring, & Reconstructing Historic Buildings. U.S. Department of the Interior, National Park Service, Washington, D.C.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Appendix A: Cost Details

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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MnDOT Maintenance Schedule for Bridge No. 5151 BRIDGE NO. 5151 MAINTENANCE Activity Listing and Costs – July 2014 Notes: 1. Costs are presented in 2014 dollars. 2. Unit costs are presented to the dollar or cent depending on the precision of the specific value. MAINTENANCE COST SUMMARY 1.00 2.00 3.00 4.00

1.00 REF. No. 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.40 1.45 1.50

2.00 REF. No. 2.05 2.10 2.15 2.20 2.25 2.30 2.35 2.40 2.45 2.50

ITEM INSPECTIONS PREVENTATIVE MAINENANCE REACTIVE MAINTENANCE REHABILITAION MAINTENANCE TOTAL

ANNUAL COSTS $425 $814 $517 $4,965 $6,721

INSPECTIONS ITEM / DESCRIPTION OF WORK Routine (initial) Routine (routine) In-Depth Special (structural issues) Special (scour damage from floods)

EXPECTED LIFE CYCLE - YEARS

ITEM QTY

QTY UNIT

1 2 As needed As needed As needed

1 1 1 1 1

LS LS LS LS LS

UNIT COST

ITEM TOTAL

ANNUAL COST

$ 300 $250 $ $ $ $ $ $ $ $

TOTAL

$300 $250 $ $ $ $ $ $ $ $ $550

$300 $125 $ $ $ $ $ $ $ $ $425

UNIT COST

ITEM TOTAL

ANNUAL COST

$700

$700

PREVENTIVE MAINTENANCE ITEM / DESCRIPTION OF WORK Power wash/flush railings, drainage system, deck cracks, joints, bridge seats, fascia beams, abutment ends, wingwalls, and pier ends Seal cracks in original concrete Seal cracks in concrete wearing course, sidewalks and curbs Spot paint steel Seal concrete deck surfaces Seal deck joint seals Seal concrete railing posts (if applied)

EXPECTED LIFE CYCLE - YEARS

ITEM QTY

QTY UNIT

1

1

LS

$700

5

1

LS

$100

$100

$20

5

1

LS

$700

$700

$140

5 7 8 7

1 5681 1 1

LS SF LS LS

$700 $0.35 $900 $800 $ $ $

$700 $2,000 $900 $800 $ $ $ $5,200

$140 $286 $113 $115 $ $ $ $814

TOTAL

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan 3.00 REF. No. 3.05 3.10 3.15 3.20 3.30 3.25 3.35 3.40 3.45 3.50 3.55 3.60 3.65 3.70

Bridge No. 5151

REACTIVE MAINTENANCE EXPECTED LIFE CYCLE - YEARS

ITEM / DESCRIPTION OF WORK High Priority (0-1 years of observation) Debris removal, erosion repair and protection, and clean up after flood events Repair scour damage to substructure units Repair damage caused by vehicular accidents Repair spalls on railing post surfaces Repair deep spalls in bridge deck Medium Priority (1-3 years of observation) Repair small spalls or delaminations in driving lanes Repair minor erosion around the abutments and wingwalls Seal crack in NE endpost Repair damage to globes Replace LEDs Repair electrical system components Low Priority (3+ years of observation) Touch up faux finish on globes Repair non-structural spalling/deterioration of pier, abutments, wingwalls, and curb surfaces Remove excessive brush growth on embankments adjacent to wingwalls

ITEM QTY

QTY UNIT

UNIT COST

ITEM TOTAL

ANNUAL COST

As needed

$

$

$

As needed

$

$

$

As needed

$

$

$

5 15

1 1

LS LS

$500 $1,000

$500 $1,000

$100 $67

7

1

LS

$800

$800

$115

$

$

$

As needed 5 As needed As needed As needed

1

LS

$100 $ $ $

$100 $ $ $

$20 $ $ $

As needed

4

Each

$100

$400

$100

10

1

LS

$1,000

$1,000

$100

7

1

LS

$100

$100

$15

$ $ $ $ $

$ $ $ $ $ $3,900

$ $ $ $ $ $517

3.75 3.80 3.85 3.90 3.95

TOTAL

4.00 REF. No. 4.05 4.10 4.15 4.20 4.25

REHABILITATION MAINTENANCE ITEM / DESCRIPTION OF WORK Repair and complete repaint of steel railing panels Repair light standards, replace gaskets, and complete repaint Clean and reapply faux finish to globes Repair railing posts (if silane treatment is not applied) Remove and replace wearing course, and repair deck

EXPECTED LIFE CYCLE - YEARS

ITEM QTY

QTY UNIT

20

158

LF

20

4

Each

$1,000

$4,000

$200

20

1

LS

$300

$300

$15

20

1

LS

$10,000

$10,000

$500

25

1

LS

$70,000

$70,000

$2,800

$ $ $ $ $

$ $ $ $ $ $113,300

$ $ $ $ $ $4,965

4.30 4.35 4.40 4.45 4.50

UNIT COST $250

TOTAL

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ITEM TOTAL $29,000

ANNUAL COST $1,450

Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Appendix B: Specifications for Maintenance and Repair Materials

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Specifications for maintenance and repair materials Stain for concrete repairs • • •

Manufacturer: Scofield Systems Product: LITHOCHROME Chemstain Classic o Equivalent products shall be allowed Color: Blends of oxide and black o Colors shall be blended to match color of repair area, exact ratios may vary. Repeated acid washes may be required to achieve desired effect. Test panels should be prepared to test color ratios prior to application on the bridge

Caulk for seal cracking of original concrete • • •

Manufacturer: BASF Product: Sonolastic NP2 o Equivalent products shall be allowed Color: Stone o Substitute colors are not allowed

Finish coat for steel railing panels and light standards • • •

Manufacturer: Sherwin Williams Product: Acrolon 218 S/G o Equivalent organic zinc-rich products shall be allowed Color: Federal Standard 595C #24097 (Federal Green) o Substitute colors are not allowed

Finish coat for steel deck drains • • •

Manufacturer: Sherwin Williams Product: Acrolon 218 S/G o Equivalent organic zinc-rich products shall be allowed Color: Federal Standard 595C #27038 (Black) o Substitute colors are not allowed

Light standards and globes • • •

Manufacturer: Union Metal of Canton, Ohio Product: See plan sheet at the end of this section for component part numbers o Substitute products are not allowed Color: o Light standards: Federal Standard 595C #24097 (Federal Green) o Globe: Clear alabaster ripple with faux finish applied to interior surface  Faux finish shall be an opal acrylic beige backing and brown veining with a clear mat urethane finish coat, type FAH7 by Winona Lighting  Faux finish shall be hand-painted to match original globes.

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Luminaire • •

Manufacturer: Cree Product: BXRAAH traditional post-top LED upgrade kit o Substitute products meeting the following criteria are allowed:  Color temperature: 4000K (approximate)  Light output: 4500 lumens (approximate)  Light source must fully and evenly illuminate the globe • No heat sinks allowed above light source • If luminaire has multiple light sources (point sources), unit must not produce multiple visible hot spots through globe

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Minnesota Department of Transportation Historic Bridge Management Plan Bridge No. 5151

Figure 10. Plan for Lights with Union Metal Part Numbers for Castings

Inspection and Maintenance Plan

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

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Appendix C: Concrete Repair and Stain Application Procedures

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

In order to maintain the aesthetics of the bridge, concrete that was placed during the 2013 rehabilitation to repair or replicate original features, including the upper portions of the abutment wingwalls, deck fascia and railing posts, was custom finished and stained to blend it with the original concrete in terms of surface texture/finish, detail, color, and weathering. Since the aesthetic characteristics of different parts of the bridge vary, treatments also varied based on location. The following is a summary of procedures used to repair different features and to blend the repairs with the original concrete to maintain the aesthetics of the structure. Future repairs should follow these procedures to ensure that they blend with the original concrete and are consistent with the repairs made as part of the 2013 rehabilitation. Abutment Wingwalls and Deck Fascia Given the amount of concrete required to reconstruct the upper portions of the abutment wingwalls and adjacent deck fascia, standard mix concrete was used. The aggregate in this concrete did not match that of the original concrete. The aggregate in the original concrete was river rock that varied in size and color, and which generally had rounded edges (Figure 10). The aggregate in the new concrete was a lighter and more consistent color, with hard, angular edges. Therefore, to achieve a surface appearance that matched and blended with the original concrete, aggregate matching found in the original concrete in terms of material, color, shape, dimensions, and surface texture, was rubbed into the surface of the new concrete before it cured (Figure 11). Since plywood forms were used to pour these features, after the concrete cured, horizontal lines were scored into the new concrete to simulate the “board form” lines found on the original concrete, which is an important visual element of the bridge. During future repairs this step could be eliminated by using board forms to repair and reconstruct historic features.

Figure 11. Spalled Area with Aggregate in Original Concrete Exposed

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 12. Aggregate Rubbed Into Surface of New Concrete

After the new concrete cured and was finished, a chemical stain finishing system was applied to the new concrete. The purpose of the finishing system was to blend the aesthetic appearance of the new concrete with the remaining original concrete in terms of color and weathering. The finishing system included the application of a coat of stain, which was then acid washed to blend it with the original concrete. As needed, additional acid washes were done until the desired effect was achieved. The product used to finish the new concrete was Scofield Systems’ LITHOCHROME Chemstain Classic with a matte finish. This product shall be used for any repairs. Prior to application, the stain was custom blended to get colors that were a close match to the color of the original concrete adjacent to the repair. The starting point was a 75/25 blend of oxide and black. Prior to staining, proportions must be adjusted as needed to achieve a good match with the original concrete adjacent to the area to be stained. To ensure the colors will match the original concrete, test panels should be prepared to compare the stain mix color against the original concrete (Figure 12). As needed, pigment ratios may need to be adjusted until a close match is achieved. The stain should then be applied per manufacture specifications at 100% coverage (Figure 13). As part of future repairs, only new concrete should be stained. Original concrete should never be stained. After the stain is applied, it should be acid washed to lighten the stain until it has the same color and darkness as the adjacent original concrete. Repeated acid washed may be required to achieve the desired aesthetic effect. Acid washes should be done by hand using a polypropylene scrub brush (Figures 13-14).

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 13. Concrete Stain Sample Panels

Figure 14. Applying Concrete Stain

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 15. Staining Completed

Railing Posts The original railings posts exhibit varying degrees of weathering. To simulate the weathered texture of the remaining original concrete, concrete repairs were applied by hand. New concrete was applied with a trowel and allowed to set (Figures 15-16). While still wet, repairs were lightly sprayed with water from a spray bottle to texture the surface of the new concrete to blend with the historic concrete (Figure 17). Only concrete “paste” was removed by this process; all aggregate was left in place. If after the concrete cures, any repairs that require additional finishing to blend them with the historic concrete should be micro-blasted. After the repairs cured, a chemical stain finishing system was applied to the new concrete. The purpose of the finishing system was to blend the aesthetic appearance of the new concrete with the adjacent original concrete in terms of color and weathering. The finishing system included the application of a coat of stain, which was then acid washed to blend it with the original concrete. As needed, additional acid washes were done until, the desired effect was achieved. The stain product used to finish the new concrete was Scofield Systems’ LITHOCHROME Chemstain Classic with a matte finish. This product shall be used for any repairs. Prior to application, the stain was custom blended to get colors that were a close match with the color of the original concrete adjacent to the area to be stained. The base mix was a 75/25 blend of oxide and black. Proportions should be adjusted as needed to achieve a good match with the original concrete adjacent to the area to be stained. To ensure the colors will match the original concrete, test panels should be prepared to compare stain mix colors against the original concrete (see Figure 12). As needed,

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

pigment ratios may need to be adjusted until a close match is achieved with the original concrete. The stain should then be applied per manufacture specifications at 100% coverage (Figure 18, see Figure 13). As part of future repairs only new concrete should be stained, original concrete should never be stained. After the stain is applied, it should be acid washed to lighten it until has the same color and darkness as the adjacent original concrete. Repeated acid washed may be required to achieve the desired aesthetic effect. Acid washes should be done by hand using a polypropylene scrub brush (see Figures 13 and 18). On railing posts exhibiting significant amount of dirt and carbon accumulation, after the concrete repairs were stained to match the color of the adjacent original concrete, a charcoal wash was applied to the repairs to simulate the weathering on the original concrete. This process consisted of mixing (diluting) charcoal powder in water to create an approximately 5% solution. This mixture was then poured on the repair and allowed to flow down the side of the post. As needed, repeated applications were applied to achieve the desired effect (Figure 19).

Central Modern Streetcar project (NCMS) Figure 16. Concrete Repair to Railing Post

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Nicollet-

Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 17. Concrete Repair to Railing Post

Figure 18. Spraying Water on Concrete Repairs to Add Texture to Simulate Weathered Concrete

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Minnesota Department of Transportation Historic Bridge Management Plan Inspection and Maintenance Plan

Bridge No. 5151

Figure 19. Acid Washing to Lighten the Stain and Blend with Original Concrete

Figure 20. Charcoal Wash Immediately After Application

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