Concrete Bridge Rail and Approach Rail Repairs Specifications.docx

CONCRETE BRIDGE RAIL AND APPROACH RAIL REPAIR SPECIFICATIONS

CONTRACT INFORMATION

SCOPE OF WORK

A. Description. The eastbound bridge over the Clark Fork River on Interstate 90 at R.P. 53.7 (SID #01361 Link for reference) has concrete bridge rail damage in 2 separate locations:

1. On the west end of the bridge (span 1), left side of the bridge, the concrete bridge barrier rail is damaged for approximately 4 feet and a single, 10-foot section of the concrete approach rail was displaced, but undamaged. Reset and realign the concrete approach guardrail section. Repair 4 feet of damaged concrete bridge rail by removing the damaged section and any additional length of bridge rail necessary to splice in new longitudinal reinforcing bars. Supply all new nuts, washers, transitions, connecting pins, concrete, epoxy coated reinforcing bars, and any other miscellaneous materials or hardware necessary for completing the installation. Field verify all dimensions, damage quantities, and new repair materials needed before ordering or fabricating.

2. On the right side of the bridge (span 3), the concrete bridge barrier rail is damaged for approximately 16 feet. Repair the 16 feet of damaged concrete bridge rail by removing the damaged section and any additional length of bridge barrier rail necessary to splice in new longitudinal reinforcing bars. In areas where the vertical hoop reinforcing bars are broken, bent, or distorted and not reusable (approximately 10 linear feet of barrier rail), remove the barrier rail down to the level of the deck and drill and epoxy in new vertical hoop reinforcing. Supply new epoxy coated reinforcing bars and any other miscellaneous materials or hardware necessary for completing the installation. Field verify all dimensions, damage quantities, and new repair materials needed before ordering or fabricating.

B. Plans. No new plans or details were developed for this project. The repair of this bridge is intended to return the structure to pre-impact damage conditions. Match new approach rail or guardrail to the existing height of the undamaged section of rail where the new section ties in. Supply materials and construct all repairs in accordance with the attached as-built plan sheets or standard detail drawings:

1) SBR-BRR

2) MDT Section 606 Standard Detailed Drawings number 605.

CONTRACT TIME

A. Description. The contract work begins on a date mutually agreed upon by the contractor and MDT, after the issuance of the Purchase Order, but no later than August 18th, 2025. The work is to be completed in 10 continuous working days, starting on the mutually agreed upon date. No work is allowed on Saturdays, Sundays, or holidays.

1. Liquidated Damages. For work not completed within 10 working days after the mutually agreed to start date, liquidated damages will be assessed in the amount established by Subsection 108.08 of the Specifications.

CONCRETE BRIDGE RAIL

A. Description. Repair damaged concrete bridge rail. In the damaged locations remove the temporary “W”-beam installed by MDT Maintenance over the damaged areas. Remove unsound concrete and damaged reinforcing bars, plus remove an additional length of concrete bridge rail necessary to properly lap splice new reinforcing bars to existing reinforcing bars. Lap length for a #4E reinforcing bar is 26 inches and for a #5E bar is 32 inches. Salvage and reuse any existing vertical or “U” reinforcing bars that are undamaged. Remove and replace any unsalvageable reinforcing bars with new bars in accordance with the plans by either lapping to existing bars or in accordance with the EPOXY-GROUTED REBAR special provision with a 5-inch minimum embedment. The estimated total length of the concrete bridge rail needing removal for repair is approximately 20 linear feet.

B. Construction Requirements

1. Inspection of Repair Areas

a. Remove all delaminated, cracked, disintegrated, loose, or otherwise unsound concrete.

b. Remove all concrete to allow for adequate slice of the reinforcing steel.

c. If the Project Manager discovers any amount of unsound concrete while performing a final check on a removal area, rework that entire area.

2. Concrete Removal

a. Provide a saw cut ½ inch deep around all removal boundaries.

b. Use mechanical equipment to remove areas of unsound concrete to reveal sound concrete. Use mechanical equipment or Jackhammers of a nominal 15 lb. class or smaller. If the bond between existing concrete and reinforcing steel breaks, remove concrete adjacent to the bar at least 1 inch beyond the bar. Use care to prevent cutting, stretching, damaging epoxy coatings, or other damage to exposed reinforcing steel.

c. Clean and remove debris in repair areas after removing concrete.

3) Reinforcing Steel

a) If an existing reinforcing bar has less than 1-inch clearance from the new finished concrete surface, remove concrete from under the bar, then press it down and fasten it in place to provide that clearance.

b) Replace any damaged reinforcement and provide an adequate splice to undamaged reinforcement.

c) Paint any areas of reinforcement with damaged epoxy coating or areas that have been blasted clean of epoxy during sandblasting with epoxy coating paint.

4) Placing and Finishing Concrete

a) If applicable, follow Cold Weather Concreting requirements as specified in section

551.03.6 of the Standard Specifications.

b) Prior to placing new concrete, use an aggregate blast on all exposed concrete and non-epoxy coated reinforcement surfaces that will have contact with the new concrete to remove all dirt, laitance, oil, other foreign materials, and any remaining unsound concrete.

c) Continue the blasting until one pass produces no color change in the concrete surface from the previous one. Temporarily protect epoxy coated reinforcing during sandblasting operations.

d) Form up the repair area to match the existing profile of the surrounding concrete curb. Clean off the repair area with filtered compressed air (free of oil and water) and condition the existing concrete that will be in contact with fresh concrete to SSD (saturated surface dry) condition immediately prior to placing the new concrete. Place new concrete in repaired areas level and flush to the existing concrete surface.

e) Do not attach forms to existing reinforcing bars unless the Project Manager gives prior approval to do so.

C. Materials

1) Repair Concrete. Use Class General Concrete, or a pre-bagged, commercially available rapid setting cementitious repair material for all new concrete placed in these repair areas meeting the requirements of the plans and specifications.

D. Basis of Payment. Include all costs associated with providing all materials, labor and tools necessary to complete the work in the lump sum bid for Repair Rail.

EPOXY-GROUTED REBAR

A. Description. This work involves drilling existing concrete to receive the new reinforcement, cleaning the holes, furnishing the bonding agent, and bonding the reinforcing bars in place.

B. Materials. Use an epoxy-resin adhesive meeting AASHTO M235 Type IV requirements.

C. Construction Requirements

a. Position holes as close as possible to the location indicated on the plans. Existing reinforcing may be encountered during drilling. Reposition hole if rebar is encountered. Fill abandoned holes with epoxy prior to pouring barrier concrete.

b. Clean holes to remove all traces of loose material. Adhere to the manufacturer’s recommendations for, drilling, cleaning, and preparing holes, but at a minimum, alternately brush and blow out with compressed air, each hole at least 3 times.

c. Install grout and bar in accordance with the manufacture’s recommendations and completely fill the hole.

d) Submittals. Submit manufacturer’s product information for all materials used to the Project Manager for approval prior to performing the work. Do not begin installation prior to receiving approval.

e) Method of Measurement and Basis of Payment. Include all costs associated with providing all materials, labor, and tools necessary to complete the work in the lump sum bid for Repair Rail.

BRIDGE APPROACH SECTION

A. Description. Retain, reset, and realign all sections of existing concrete approach rail that are out of place due to impact on the west end of the bridge, left side. Remove temporary W-beam that has been attached to the concrete approach rail and concrete bridge rail that spans over the damaged rail location. Provide and install any necessary hardware that is necessary to tie the concrete approach rail into the repaired concrete bridge rail.

B. Construction Requirements. Reset and realign bridge approach concrete rail and supply and install any hardware or connection components as necessary.

C. Materials. Use all new materials unless otherwise specified in these provisions.

D. Basis of Payment. Include all costs associated with providing all materials, labor and tools necessary to complete the work in the lump sum bid for Repair Rail.

DISPOSAL AND SALVAGE OF MATERIALS

A. Description. Dispose of all bituminous material, concrete, reinforcing steel, posts, w-beam, and other materials not specifically mentioned as salvage and removed from the approaches and structures to the satisfaction of the Project Manager, in conformance with the Montana Solid Waste Management Act and other applicable laws, rules and regulations. This removal includes any concrete, steel posts, rails, or w-beam that was damaged in the impact and laying onsite in the MDT right-of-way. Do not waste material within the limits of the MDT right-of-way.

TEMPORY BRIDGE RAIL

A. Description. Multiple sections of temporary W-Beam rail are in place over the damaged section or bridge barrier rail. Remove these temporary sections and all bolts associated with the installation. Fill any holes from the bolts with a grout material. Remove, return, and stockpile the sections of temporary w-beam rail to the Superior Maintenance yard at the completion of the project. Contact Kevin Managhan, at (406) 822-3386, three days prior to delivery to coordinate specific delivery time and date and stockpile location in the yard.

TRAFFIC CONTROL AND SEQUENCE OF OPERATIONS

A. General. Coordinate and conduct work to minimize inconvenience to the traveling public. Accomplish traffic control in accordance with the plans, these special provisions, standard specifications, Detailed Drawings, and the Manual on Uniform Traffic Control Devices (MUTCD) in addition to the following:

B. Sequence of Operations.

C. Submit a proposed Traffic Control Plan fitting the geometries of the location and requirements of these special provisions to the Project Manager for approval at least 10 days prior to the onsite lane closure and work. Include in the plan any temporary concrete median rail, temporary impact attenuators, candles or cones, all construction signs and locations, temporary striping, location of arrow/information light boards, any flaggers, and any signals or lights needed for each phase of construction. Also include a construction timeline detailing beginning and end times for all work and the proposed date that the work will begin. All traffic control devices must be in new or like-new condition and must be maintained for the duration of the work.

D. Maintain a minimum of single lane traffic through the project on I-90 eastbound at all times. Do not disturb I-90 westbound traffic.

E. Basis of Payment. All costs for all traffic control operations will be paid for in the Lump Sum bid item Repair Rail.

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REVISED: 823/04