B. Samples: Cured samples of materials as required by Architect/Engineer.

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1 SECTION PART 1 - GENERAL 1.01 SUMMARY A. Provide all labor, equipment and materials required to repair spalled, deteriorated or structurally damaged concrete surfaces. Depth of repairs shall be adequate to restore concrete to original dimensions after proper preparation to sound concrete. The contractor shall repair all concrete surfaces as shown on contract drawings or as specified herein. B. This section includes partial and full-depth removal of concrete, removal of concrete and rust from reinforcing, and various types of patching and rebuilding. 1. Removal of deteriorated concrete and subsequent patching, rebuilding, and leveling. including sawing out cracked slab edges and rebuilding joint nosings. 2. Reinforcement Bar Preparation 3. Corrosion-inhibiting treatments of concrete and concrete reinforcement. 4. Horizontal, Vertical and Overhead concrete repairs. 5. Floor joint repair 6. Epoxy crack repair to concrete 1.02 SUBMITTALS A. Product Data: Submit manufacturer s data and application instructions for specified materials. 1. Include Material Safety Data Sheets as requested. B. Samples: Cured samples of materials as required by Architect/Engineer. C. Qualification Data: For products required to be installed by workers approved by product manufacturer, include letters of acceptance by product manufacturer certifying installers are approved to apply their products QUALITY ASSURANCE A. Contractor shall have experience and proficiency specific to the application type and shall be approved by the Architect/Engineer and the material supplier. B. Manufacturer shall provide job service as required to assure proper handling and installation of materials. The field representative shall instruct as needed to assure that handling, mixing, placing and finishing of materials are in accordance with specifications. C. Pre-Installation Conference: 1. Arrange a meeting not less than 30 days before starting work. 2. Attendance: GC, A/E, Manufacturer's Representative and Applicator s representative D. Source Limitations: Provide concrete patching and rebuilding materials from a single manufacturer, unless noted otherwise in the Contract Documents REFERENCES ACI 302.1R-89, Guide for Concrete Floor and Slab Construction ACI 304 R-89, Guide for Measuring, Mixing, Transporting and Placing Concrete ACI 305, Hot Weather Concreting ACI 306, Cold Weather Concreting ACI , Section 12, Development and Splices of Reinforcement ACI 362 R-85, State-of-the-Art Report on Parking Structures

2 SECTION ACI 503.4, Standard Specification for Repairing Concrete with Epoxy Mortars ACI 504 R-90, Guide to Sealing Joints in Concrete Structures ACI 506R-85, Guide to Shotcrete ASTM C-33, Specification for Concrete Aggregates ASTM C-881, Specification for Epoxy Resin Base Bonding Systems for Concrete ASTM C-882, Test Method for Bond Strength of Epoxy Resin Systems Used with Concrete ICRI Technical Guideline No , Guide for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion. ICRI Technical Guideline No , Guide for Selecting Application Methods for the Repair of Concrete Surfaces. ICRI Technical Guideline No , Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings and Polymer Overlays. ICRI Technical Guideline No , Guide for Selecting and Specifying Materials for Repair of Concrete Surfaces. ICRI Technical Guideline No , Guide for Verifying Field Performance of Epoxy Injection of Concrete Cracks DELIVERY, STORAGE, AND HANDLING A. Deliver materials to project site in manufacturer s unopened containers with labels intact. B. Materials shall be stored on site under dry conditions and protected from contamination. C. Comply with the manufacturer s instructions, recommendations and precautions pertaining to delivery, storage and handling of materials PROJECT/ENVIRONMENTAL CONDITIONS A. Environmental Precautions/Limitations for Epoxies: Do not apply when air and substrate temperatures are outside limits permitted by manufacturer. During hot weather, cool epoxy components before mixing. Do not apply to wet substrates unless approved by manufacturer. 1. Use Class A epoxies when substrate temperatures are below or are expected to go below 40 o F (5 o C) within 8 hours. 2. Use Class A or B epoxies when substrate temperatures are below or are expected to go below 60 o F(16 o C) within 8 hours. 3. Use Class C epoxies when substrate temperatures are above 60 o F (16 o C). B. Cold Weather Precautions/Limitations for Cementitious Materials: Do not apply unless air temperature is above 40 o F (5 o C) and remains so for a minimum of 24 hours after completion of Work. Do not apply to frozen concrete. (ACI 306 Cold Weather Concreting) C. Hot-Weather Precautions/Limitations for Cementitious Materials: Protect repair work when temperature and humidity produces rapid drying conditions for patching materials. Provide artificial shade and wind breaks, and cool materials as required. Do not apply to substrates with temperatures above 90 o F (32 o C). (ACI 305 Hot Weather Concreting) D. New concrete must be cured properly for 28 days. Job conditions shall be maintained at standards that allow material placement within temperature and cleanliness requirements. E. Unusual conditions as uncovered during the course of work shall be brought to the Architect/Engineer s attention for analysis and disposition. These conditions include but are not limited to poor quality base concrete, severely corroded reinforcing steel, random cracks and deep oil penetration. 2

3 SECTION WARRANTY A. Deliver to Architect signed copies of the following written warranties against defective materials and workmanship. 1. Manufacturer s standard warranty covering materials. 2. Applicator s standard warranty covering workmanship. PART 2 - PRODUCTS 2.01 MANUFACTURERS A. Acceptable Manufacturers: 1. Basis for design is the following materials as manufactured by The Euclid Chemical Company and Simpson Company as based on the listed selection of individual materials for each repair type. B. Other Manufacturers: 1. For Architect s approval of other manufacturers as an acceptable equivalent:, the Contractor shall provide product data and samples per the requirements of this Section and comply with the provisions of the Division 01 section(s) pertaining to Substitutions prior to the Bid Due Date. 2. Substitutions: No submittals for substitutions will be accepted after the bid date MATERIALS (Refer to the Drawings for Details) A. Epoxy/Cement Protective Coating for Reinforcing Steel: Dural Prep AC B. Penetrating, Migratory Corrosion Inhibitor: Dural Prep 3020 C. Epoxy/Cement Bonding Agent [ASTM C-882]: Dural Prep AC D. Horizontal Patch & Repair: 1. Rapid Set: Speed Crete 2028 E. Vertical/Overhead Repairs: 1. Rapid Set: Speed Crete Red Line F. Epoxy Crack Injection Adhesive: 1. Eucopoxy Injection Resin 2. Simpson Crack Pac-Epoxy G. Crack Repair Gravity Feed 1. Doral 50LM H. Concrete Patch Infills on Horizontal Deck and Railing Patch: 1. NC grout 2.03 ACCESSORY MATERIALS A. Evaporation Retardant: Eucobar B. Curing and Sealing Compounds: Super Aqua Cure VOX and Super Diamond Clear Vox, Kurez DR VOX

4 SECTION C. Joint Filler Stain Prevention Film: Euco Clean Cut PART 3 - EXECUTION 3.01 PREPARATION A. Concrete Removal: (Horizontal, Vertical, Overhead) Saw-cut perimeter of areas indicated for removal to a depth of at least 1/2 inch. Make cuts perpendicular to concrete surfaces and no deeper than cover on reinforcing. Remove loose and deteriorated concrete by breaking up and dislodging from reinforcing. 1. Remove concrete between cuts to a depth of at least 1/2-inch. 2. Where half or more of the perimeter of reinforcing bar is exposed, bond between reinforcing bar and surrounding concrete is broken, or reinforcing bar is corroded, remove concrete from entire perimeter of bar to provide at least a 3/4-inch clearance. 3. Test areas where concrete has been removed by tapping with hammer, and remove additional concrete until unsound concrete is completely removed. 4. Provide exposed aggregate surfaces with a profile of at least 1/8 inch that are approximately perpendicular or parallel to original concrete surfaces. Thoroughly clean removal areas of loose concrete, dust, and debris. B. Reinforcing Bar Preparation: Perform surface preparation in compliance with ICRI Technical Guideline No Remove all heavy corrosion and scale from the bar as necessary to promote maximum bond of replacement material by high-pressure water cleaning, abrasive blast cleaning, needle scaling, or wire brushing. If a protective coating is to be applied to the bar surface, preparation should be to a white metal or near white metal finish. 1. Where cross section loss of reinforcing bar is greater than 20 percent, Architect/Engineer shall be notified. Cut bars and remove and replace as directed by Architect/Engineer. Remove additional concrete as necessary to provide at least a 3/4-inch clearance at existing and replacement bars. Splice replacement bars to existing bars according to ACI 318, by lapping, welding, or using mechanical couplings. 2. Provide for 60 feet (various lengths) of #5 rebar replacement in the Lump Sum Base Bid for Work of the Project. C. Preparation of Floor Joints for Repair: Saw-cut joints full width to edges of spalls and to a depth of at least 1-inch. Clean out debris and loose concrete; vacuum or blow clear with compressed air. Select acceptable methods and profile in first paragraph below to suit conditions and overlay used. See ICRI D. Surface Preparation for Crack Repair: Remove all dirt, dust, foreign contaminants and laitance by blowing out cracks with oil free compressed air. Care must be taken if saw cutting or crack chasing is done so as not to fill the crack with fines that will block the penetration of the low viscosity repair material INSPECTION AND TREATMENT OF REINFORCING STEEL A. All reinforcement that is loose shall be secured in its proper position by tying to other secured bars. B. Exposed rebar shall be treated with two 20 mils each of Dural Prep AC anti-corrosion coating. C. Prepare steel reinforcing as outlined above. 4

5 SECTION JOINTS A. Existing joints shall be maintained by forming at joint locations or sawcutting over joint locations MIXING A Mixing of Epoxy-Cement Bonding Agent and Anticorrosion Agent: 1. Shake Part A before combining Part A with Part B. Add the entire container of Part B to all of Part A. Mix with a mechanical drill for 2 3 minutes until uniform. Add Part C (powder) and blend until the powder is completely wetted and lump free. Apply immediately. B. Mixing of Cement-based Mortar Scrub Coat: 1. Mix repair mortar as instructed. Add up to one pint of additional mixing liquid to repair mortar as per manufacturer's recommendations. C. Mixing of Repair Mortars: 1. Small quantities may be mixed with a drill and jiffy type mixing paddle. Use a paddle type mortar mixer for typical jobs mixing up to four (4) units at a time. For large or pumped jobs, bulk bagged material mixed in a ready mix truck or a mixer pump combination may be used where workability permits. All materials should be in the proper temperature range of 60 o F (15 o C) to 90 o F (32 o C). Mix time for most mortars will be 3 5 minutes. If pea gravel aggregate is added, mix an additional 2 3 minutes after its addition. The mixed product should be transported to the repair and placed immediately. D. Mixing of Epoxy Resins: 1. Premix Part A and Part B of all pigmented epoxy resins for 1 minute. Thoroughly mix together Part A and Part B for 2 3 minutes using drill and proper mixing paddle. For ease of mixing always add Part B to the Part A. The epoxy resin must be mixed well to ensure proper chemical reaction. Place material immediately after mixing. 2. When making an epoxy mortar, mix Part A and Part B for a minimum of 2 minutes as outlined above. After mixing, add Part C (aggregate) and continue to mix for an additional 2 minutes or until aggregate pieces are completely covered by the epoxy. Place material immediately after mixing. 3. Materials available in cartridges must be shaken well before use. Static mixing nozzles should be supplied by manufacturer with cartridges for mixing and application of material INSTALLATION A. Epoxy-Cement Anti-corrosion Coating: 1. For maximum protection of steel reinforcement, apply epoxy-cement protective coating in two coats. Allow first coat to dry to tack free before applying second coat. Total film thickness must be a minimum of 40 mils. All steel must be completely coated. Fresh concrete or repair mortar must be placed within the maximum allowable time. B. Bonding Agent: After the concrete surface has been prepared, cleaned and left in a SSD (saturated surface dry) condition, apply one coat of bonding agent at a rate not to exceed 80 square feet per gallon of mixed material. Coating thickness shall be a minimum 20 mils thickness. In lieu of an application of epoxy-modified bonding agent, a scrub coat of the repair mortar is acceptable according to the manufacturer s recommendations.

6 SECTION C. Mortar Scrub-Coat: Prepare repair area to SSD (saturated surface dry) condition. Remove standing water and apply scrub-coat with a brush, scrubbing it into surface and thoroughly coating repair area. If scrub-coat dries, recoat before applying patching mortar or concrete. D. Epoxy Bonding Agent: Apply to concrete by brush, roller, or spray at a rate not to exceed 80 square feet per gallon, leaving no pinholes or other uncoated areas. Apply patching mortar or concrete while epoxy is still tacky. If bonding agent dries, recoat before placing patching mortar or concrete. E. Repair Mortar: Unless otherwise recommended by manufacturer, apply as follows: 1. For horizontal patching, wet substrate thoroughly and then remove standing water. Apply bonding agent or scrub coat of neat repair mortar into substrate, filling pores and voids. Place mortar by troweling toward edges of patch to force material against edges. On large areas, use screed strips or forms and screed to level with hand held straightedge. At fully exposed reinforcing bars, force patching mortar to fill space behind bars by compacting with trowel from sides of bars. 2. For vertical patching, wet substrate thoroughly and allow excess water to run off. Apply bonding agent or scrub coat of neat repair mortar into substrate, filling pores and voids. Make initial placement of material at approximately 1/4 inch to provide base for higher build. Place material in lifts of 1 inch to 2 inches, but not less than 1/8 inch. Do not feather edge. 3. For overhead patching, wet substrate thoroughly. Apply bonding agent or scrub coat of neat repair mortar into substrate, filling pores and voids. Make initial placement of material at approximately 1/4 inch to provide base for higher build. Place material in lifts of not more than 1 inch to 2 inches, but not less than 1/8 inch. Do not feather edge. 4. After each lift is placed, consolidate material and screed surface. 5. Where multiple lifts are used, crosshatch surface of previous lifts to provide for a secure bond for next lift. Allow each lift to reach final set before placing subsequent lifts. 6. Allow surfaces of lifts that are to remain exposed to become firm and then finish surface with a wood or sponge float, broom or burlap drag. 7. Do not add additional water to the surface during finishing operation. If additional liquid is required, use Eucobar Finishing Aid. 8. Proper curing procedures are required to ensure the durability and quality of the repair. Use curing compound listed above as per manufacturers recommendation. In lieu of a curing agent, wet-cure the repair and cover with polyethylene for a minimum of 3 days. 9. DO NOT RETEMPER ANY REPAIR MORTAR. ONCE PRODUCT BEGINS TO SET (HARDEN), DISGARD AND MIX FRESH MATERIAL F. Shotcrete Repairs: Apply in accordance with the recommendations of ACI 506R-90, Guide to Shotcrete. Pay special attention to the angle of the application (i.e. 90 O ) and distance from the site of repair, normally 2 ft. to 6 ft. Typical application depths range from 1/2 inch to 6 inches. If placement at a depth greater than 6 inches is required, cross hatch the surface of the initial layer. After the surface has sufficiently hardened, additional layers may be shot. G. Epoxy Joint Filler (TENNIS COURT DECK): Install in nonmoving floor joints where indicated. Joint depth is critical to a successful application. Saw cut joints should be 25% of the thickness of the slab (i.e., a 4-inch thick slab should be cut a minimum 1-inch deep.) It is recommended that the full depth of the joint be filled with the epoxy joint filler for proper load transfer. 6

7 SECTION Joints should be filled full depth. Avoid using silica sand, backer rods or compressible fillers below the epoxy joint filler. 2. Pour mixed material into the joint, filling it approximately 2/3 its full depth. Allow filler to settle and then complete filling within 1 hour so that when cured, it is flush at top surface of adjacent concrete. If necessary, overfill joint and remove excess when filler has cured. 3. Wipe up excess epoxy on deck surface and then spread sand on epoxy spilled or adjacent surfaces. H. Epoxy Crack Injection (BUILDING DECK EDGE CRACKING): Comply with the manufacturer's written instructions and the following: 1. Clean areas to receive capping adhesive of oil, dirt, and other substances that would interfere with bond, and clean cracks with oil-free compressed air or low-pressure water to remove loose particles. 2. Place injection ports as recommended by epoxy manufacturer, spacing no farther apart than thickness of member being injected. Seal injection ports in place with capping adhesive. 3. Seal cracks at exposed surfaces with a ribbon of capping adhesive at least 1/4 inch thick by 1 inch wider than the crack. 4. Begin at widest part of crack and work toward narrower parts. Inject adhesive into ports to refusal, capping adjacent ports when they extrude epoxy. Cap injected ports and inject through adjacent ports until crack is filled. 5. After epoxy adhesive has set, remove injection ports and grind surfaces smooth. I. Crack Repair by Gravity Feed (TENNIS COURT DECK): Comply with manufacturer's written instructions. 1. Clean all spilled epoxy from surface and cover with fine sand. J. Penetrating, Migratory Corrosion Inhibitor: Surface should be dry, sound, clean and free of all dirt, dust, oil, grease, efflorescence, sealers, coatings, membranes or any other contaminants. 1. Apply liberally and allow to soak into substrate. Apply by spray, roller or squeegee as per manufacturer s recommendations 3.06 CLEAN UP A. Promptly remove any repair material from adjacent surfaces with water; leave work area in broom clean condition. B. It is important to note that all epoxy spilled or covering tennis court surface must be wiped up and covered with fine sand (play sand). The Sonoguard coating will not adhere to the epoxy without a sand finish applied. END OF SECTION