Part 1 — General
1.1 Section Includes
A.Repair of delamination and cracks in structural concrete elements such as columns, pedestals, bent caps, diaphra gms, wingwalls, abutment s, girders , parapets , curbs, sidewalks, and deck edges .
1.2 Related Sections
A.Section 03055: Portland Cement Concrete
B.Section 03211: Reinforcing Steel and Welded Wire
C.Section 03310: Structural Concrete
D.Section 03390: Concrete Curing
1.3 References
A.AASHTO M 235: Epoxy Resin Adhesives
B.AASHTO T 106: Compressive Strength of Hydraulic Cement Mortar (Using 50- mm or 2 -in. Cube Specimens)
C.AASHTO T 161: Resistance of Concrete to Rapid Freezing and Thawing
D.ASTM A 780: Repair of Damaged and Uncoated Areas of Hot -Dip Galvanized Coatings
E.ASTM C 928: Packaged, Dry, Rapid- Hardening Cementitious Materials for Concrete Repairs
F.ASTM D 3963: Fabrication and Jobsite Handling of Epoxy -Coated Steel Reinforcing Bars
G.ASTM D 4285: Indicating Oil or Water in Compressed Air
H.International Concrete Repair Institute (ICRI)
1.4 DEFINITIONS Not Used
1.5 Submittals
A.Manufacturer’s product data sheets and recommended installation instructions for all products for review .
B.Evidence that epoxy injection equipment operators have at least two years of experience in the methods and materials of the selected epoxy injection system for information.
C.Working Drawings for review.
1.Girder jacking drawings
a.Submit when girder jacking is shown.
b.Provide the seal of a Professional Engineer or Professional Structural Engineer licensed in the State of Utah.
c.Include s upporting engineering calculations.
2.Drawings for Temporary Works as shown.
1.6 Delivery, Storage , and Handling
A.Deliver the concrete repair mortar, injection adhesive, and surface seal materials in unopened packages with labels clearly indicating the following:
1.Name of Manufacturer
2.Manufacturer’s product name or product number
3.Manufacturer’s lot number
4.Mix ratio
5.Hazardous material rating and appropriate warnings for handling.
Part 2 — Products
2.1 Materials
A.Concrete
1.Class AA(AE). Refer to Section 03055.
2.Aggregate – ¾ inch maximum.
B.Reinforcing Steel
1.Coated reinforcing steel according to Section 03211.
2.2 Products
A.Concrete Repair Mortar
1.Use o nly products recommended for vertical or overhead application by the manufacturer.
2.Use a product that meets AASHTO T 106 and ASTM C 928 as defined in Table 1. Table 1 Repair Mortar Type Element Type Parapets, Diaphragms, and Wingwalls R1 Deck Edges, Pedestals, Abutments, and Backwalls R2 Girders, Bent Caps, Columns, and other items R3
3.R3 concrete repair mortar may be substituted for R1 and R2 at the Contractor’s discretion.
4.Use a product that meets AASHTO T 161 Durability Factor of 95 at 28 days.
5.Use a product that dries gray in color.
B.Injection Adhesive and Surface Seal
1.Use an injection adhesive meeting AASHTO M 235.
a.Use Type IV for all applications .
b.Meet the requirements for Grade 1 for cracks that can be surface sealed on all faces.
c.Meet the requirements for Grades 1, 2 or 3 for cracks that cannot be surface sealed on all faces.
2.Use a surface seal recommended by the injection adhesive manufacturer.
a.Use seal c apable of containing injection adhesive in cracks during pressure injection and until the injection adhesive has cured.
2.3 Equipment
A.Concrete Repair Mortar Mixer
1.Use a small mixer to batch out the concrete repair mortar .
B.Epoxy Injection system
1.Use a t least two pumps having the following characteristics:
a.Electric -powered and portable
b.Positive displacement
c.Positive -ratio control of exact proportions of the two components at the nozzle
d.In-line metering and mixing
2.Automatic pressure control capable of discharging the mixed adhesive at any preset pressure up to 200 psi ± 0.5 psi and equipped with a manual pressure control override.
3.Capable of maintaining the volume ratio of the injection adhesive prescribed by the manufacturer within a tolerance of ± 5 percent by volume at any discharge pressure up to 200 psi.
4.Sensors on both the component reservoirs that automatically stop the machine when only one component is being pumped to the mixing head.
C.Sand blaster /Compressed Air
1.Verify air is free of water and oil according to ASTM D 4285.
D.Jackhammer
1.30 lb class
2.15 lb class
Part 3 — Execution
3.1 Preparation for Delamination Repair
A.Locate the repair areas .
1.Sound the items requiring this work and mark the limits of delaminated areas for repair work in the presence of the Engineer.
B.Concrete removal
1.Make ½ inch deep saw cuts in the sound concrete along the perimeter of the repair area.
2.Remove damaged, shattered, and delaminated concrete .
a.Use 30 lb class jackhammer when allowed . 1) Do not use pneumatic hammers heavier than 15 lb class for removals in areas directly below the top reinforcing steel. 2) Use 15 lb class jack hammer or lighter for deck edge repair.
b.Operate jackhammer at an angle greater than 45 degrees as measured from the element surface.
c.Protect existing reinforcing steel encountered.
d.Replace or repair damaged reinforcing steel .
3.Remove loose materials by dry sweeping or clean and dry compressed air with at least 90 psi pressure.
4.Sandblast clean exposed reinforcing steel and concrete surfaces before placing new concrete.
a.Protect in place sound rebar.
b.Prevent sandblasting material and debris from falling into waterways , pedestrian areas, traffic areas, or onto railroad tracks.
5.Verify or provide a rough concrete surface of at least ICRI Concrete Surface Profile (CSP) 5.
a.Roughen the surface of sound concrete without leaving loosened particles or damaged concrete. b. Refer to http://www.udot.utah.gov/go/standardsreferences for a CSP Examples document.
6.Clean the repair area by blowing with clean and dry compressed air at 90 psi .
7.Replace existing reinforcing steel bars with 25 percent or greater section loss.
a.Cut and remove deteriorated existing reinforcing steel bars .
b.Match the size of the new reinforcing steel bar to the existing bar.
c.Provide lap lengths to a length appropriate for the new reinforcing steel bar .
3.2 Epoxy Injection
A.General
1.Pressure inject cracks 1/64 to 1/4 inch in width.
2.Mark cracks to be pressure injected in the presence of the Engineer.
B.Preparation
1.Sandblast the concrete surfaces clean.
2.Clean cracks of contaminants using oil -free compressed air .
3.Space ports at a distance not more than the thickness of the concrete being injected.
a.Limit port s pacing at ends of cracks to not more than half the concrete thickness.
b.Adjust port spacing based on manufacturer’s recommendations and to ensure injection adhesive fills the cracks.
4.Apply a surface seal over all exterior faces of the crack that can be reached to contain the injection adhesive in the crack.
C.Epoxy Injection
1.Inject the crack when it is at its widest i f the crack width changes because of daily temperature cycles or other structural loading of the structure.
2.Proceed from lower to higher ports.
3.Plug the port being injected and move to a higher port when injection adhesive appears at the next higher port .
D.Final Surface Seal
1.Grind flush all ports extending above the concrete surfaces.
2.Mask the member in parallel straight line segments between the ends of the crack so the surface seal has a clean and neat appearance when applied.
3.Apply the surface seal at the application rate of at least
0.09 gal/yd2.
a.Cover the entire length of the crack for at least 6 inches on both sides of the crack.
4.Apply a second coat at the same application rate as soon as the first coat is dry to the touch.
a.Do not exceed the following times between coats: Table 2 Maximum Time Between Coats Temperature (Degrees F) Hours 90 72
3.3 Delamination Repair
A.Form Work
1.Use forms and braces to place new material to the original dimensions.
a.Rebuild the areas to original shape, ± ⅛ inch.
2.Vibration is required in the forms when the area between forms and existing concrete surface will allow use of vibrators.
B.Repairs with a thickness less than or equal to three inches:
1.Use concrete repair mortar .
2.Follow manufacturer’s requirements.
3.Provide saturated surface dry condition to hardened concrete prior to placing fresh concrete or repair mortar.
4.Place concrete repair mortar in layers not exceeding the manufacturer’s recommended application thickness per layer.
a.Rebuild the areas to original shape, ± ⅛ inch.
C.Repairs with a thickness greater than three inches .
1.Use concrete, or concrete repair mortar extended with aggregate .
2.Follow manufacturer’s requirements .
3.Provide saturated surface dry condition to hardened concrete prior to placing fresh concrete or repair mortar.
4.Construct falsework according to Section 03310.
5.Place and form concrete according to Section 03310.
D.Finishing and curing
1.Follow the manufacturer’s recommendations for finishing and curing.
2.Finish and c ure concrete according to Section 03390.
3.Finished Surfaces – Provide the look of one color.
3.4 Structural Concrete Repair
A.Perform work according to Table 3. TABLE 3 Structural Concrete Repair Items Item Work Required Column Repair Preparation for delamination repair Epoxy injection Delamination repair Pedestal Repair Jack girders (when shown) Preparation for delamination repair Delamination repair Bent Cap Repair Jack girders (when shown) Preparation for delamination repair Epoxy injection Delamination repair Diaphragm Repair Preparation for delamination repair Epoxy injection Delamination repair Wingwall Repair Preparation for delamination repair Delamination repair Abutment Repair Preparation for delamination repair Delamination repair Girder Repair Preparation for delamination repair Epoxy injection Delamination repair Girder End Repair Jack girders (when shown) Preparation for delamination repair Epoxy injection Delamination repair Parapet Repair Preparation for delamination repair Delamination repair Sidewalk and Curb Repair Preparation for delamination repair Delamination repair Deck Edge Repair Preparation for delamination repair Delamination repair Structural Concrete Repair Preparation for delamination repair Epoxy injection (when shown) Delamination repair Crack Repair Epoxy injection
Source: Utah Standard Specifications for Road and Bridge Construction, 2026 Edition. Pages 1089–1096 of 1,331.