PART 1 - GENERAL. Section Cast-in-Place Concrete 1.3 REFERENCES

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1 CSI SECTION CONCRETE PAVING RIGID PAVING REHABILITATION DOT APPROVED PRODUCTS LIST OR SPECIAL PROVISIONS Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Overlay EDITOR NOTE: The following guideline specification has been prepared to assist architects and design professionals in the preparation of project master specifications. It is intended for use by qualified design professionals and is not intended to be used verbatim. Appropriate modifications to meet specific project requirements are required. Make appropriate [selections] where options are provided and delete items that are not applicable to the project. Contact CTS Cement Technical Service for additional information or project specification assistance. PART 1 - GENERAL 1.1 SECTION INCLUDES A. Supply and construction of Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Overlays for new construction and repair and rehabilitation of existing structures. 1.2 RELATED SECTIONS [A. [B. Section Maintenance of Concrete Section Excavation and Fill [C. Section Concrete Overlays [D. Section Rigid Paving Repair [E. 1.3 REFERENCES Section Cast-in-Place Concrete A. ASTM C33 Standard Specification for Concrete Aggregates B. ASTM C39 Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens C. ASTM C403 Standard Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance D. ASTM C666 Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing E. ASTM C685 Standard Specification for Concrete Made by Volumetric Batching and Continuous Mixing F. ASTM C882 Standard Test Method for Bond Strength of Epoxy-Resin Systems Used with Concrete by Slant Shear G. ASTM C1600 Standard Specification for Rapid Hardening Hydraulic Cement H. ACI Specification for Hot Weather Concreting I. ACI Standard Specification for Cold Weather Concreting J. ACI Specification for Latex-Modified Concrete Overlays Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 1

2 1.4 SUBMITTALS A. General: Submit samples and manufacturer s product data sheets, installation instructions, etc. in accordance with Division 01 General Requirements Submittal Section. B. Test Data: Submit qualified testing data that confirms compliance with specified performance requirements. C. Design Mixtures: Submit design mixtures for each concrete paving mixture at least 4 weeks prior to initial concrete placement. For each concrete mixture, submit alternate design mixtures when characteristics of materials, project conditions, weather, test results, or other circumstances warrant adjustments. Maintain approved mix designs for the project with Project Contract Documents. D. Aggregates: Samples of fine and coarse aggregates to be provided by the contractor for source approval. Other samples shall be taken from shipments at intervals specified by the Engineer. E. Material Certificates: Signed by manufacturers certifying that each of the following materials complies with requirements. [1. Cementitious materials. [2. Admixtures. [3. Form materials and form-release agents. [4. Repair materials. [5. Evaporation retardant. F. Field quality control test reports. G. Minutes of pre-installation conference. 1.5 PRE-INSTALLATION MEETINGS A. Pre-installation Conference: Conduct conference at the Project Site located at [enter site address] at least three (3) weeks prior to initial concrete placement. B. Require representatives of each entity directly concerned with cast-in-place concrete to attend, including the following: [1. Contractor's superintendent. [2. Independent testing agency responsible for concrete testing. [3. Owner, Owner s Representative or Developer [4. Concrete Producer. [5. Concrete Subcontractor. [6. Cement Manufacturer. [7. Admixture Manufacturer. [8. Inspector/QC Inspector. [9. Engineer of Record. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 2

3 C. Before submitting design mixtures, review concrete design mixtures, procedures for ensuring consistent quality of concrete materials, [special inspection and testing and inspecting agency procedures for field quality control,] [concrete finishes and finishing,] [cold- and hot-weather concreting procedures,] [curing procedures,] [forms and form removal limitations,] [vapor-retarder installation,] [methods for achieving specified performance and design requirements] [concrete repair procedures,] and concrete protection. 1.6 QUALITY ASSURANCE A. Qualifications: 1. Concrete Producer: a. A company experienced in producing volumetric mobile mixed concrete and that complies with ASTM C685/C685M requirements, respectively, for production facilities and equipment. 2. Cement Manufacturer: a. Must have marketed very early high strength, low shrinkage, hydraulic cement materials in the United States for at least five years and must have completed projects of the same general scope and complexity. b. Complementary admixture materials must be manufactured by or approved for use by CTS Cement Manufacturing Corp. ( , 3. Applicator: a. Must be experienced and competent in installation of rapid hardening hydraulic cement materials and provide evidence of experience in work similar in size and scope to that required by this section. 1.7 DELIVERY, STORAGE, AND HANDLING A. Delivery: Deliver products in original, unopened, undamaged packaging with manufacturer's identification (i.e., brand logo, product name, weight of packaged unit, lot number). B. Storage: Store products in a dry location, covered, out of direct sunlight, off the ground, and protected from moisture. Maintain storage temperature required by the manufacturer. Keep materials dry until used. Store bulk sand in a well-drained area on a clean, solid surface. Take necessary precautions to prevent contamination of materials. C. Handling: Handle products in accordance with manufacturer s published recommendations. 1.8 SITE / ENVIRONMENTAL CONDITIONS A. Temperature: Maintain ambient and surface temperatures between 45 F (7 C) to 90 F (32 C). Do not apply concrete materials if substrate is frozen (32 o F/0 o C). Protect concrete from uneven and excessive evaporation during dry weather, windy conditions and strong blasts of dry air. Comply with ACI Guidelines for hot and cold weather concreting. B. Inclement Weather: Do not apply materials during inclement weather unless appropriate protection is employed. C. Substrate: Prior to installation, substrates must be inspected for surface contamination or other conditions that may adversely affect the performance of the concrete. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 3

4 1.9 COORDINATION AND SCHEDULING A. Coordinate installation of concrete materials with all other trades to avoid impeding other construction. B. Sufficient manpower must be provided to ensure continuous application and timely finishing. PART 2 - PRODUCTS 2.1 MANUFACTURER A. CTS Cement Manufacturing Corp., Knott Avenue, Cypress, CA ( , B. Components: Obtain cement and other complementary admixture and materials manufactured by CTS Cement from authorized distributors. No substitutions or additions of other materials are permitted without prior written permission from the manufacturer for this project. 2.2 MATERIALS A. Very Early High Strength, Low Shrinkage Hydraulic Cement [1. Rapid Set Low-P TM Cement: is a low-permeability, very fast setting, calcium sulfoaluminate hydraulic cement used in powder polymer-modified concrete applications. It is mixed with aggregates and water on site to create a fast setting, high performance concrete that achieves 7-day strengths in 3 hours. Integral corrosion inhibitor provides exceptional corrosion resistance. Low-P offers high strength, low shrinkage and exceptional freeze-thaw performance to achieve the highest durability and long-term performance. [2. Rapid Set Low-P/FA1 TM Cement: is a low-permeability, very fast setting, calcium sulfoaluminate hydraulic cement used in powder polymer-modified concrete applications. It is pre-blended with fly ash and mixed with aggregates and water on site to create a fast setting, high performance concrete that achieves 7-day strengths in 3 to 4 hours. Integral corrosion inhibitor provides exceptional corrosion resistance. Low-P/FA1 offers high strength, low shrinkage and exceptional freeze-thaw performance to achieve the highest durability and long-term performance. EDITOR NOTE: Modify below to suit project requirements. Define aggregate performance characteristics, approved sources, acceptable types and mix design proportions and other pertinent information regarding quality of aggregates to ensure designed concrete performance. 3. Aggregates: a. Coarse and fine aggregates for concrete must comply with ASTM C33, consist of uniform quality and be of sound, durable rock free from objectionable coatings and cemented lumps. Gravel and crushed stone must be washed. b. Percentage of deleterious substances must not exceed 3.0 percent unless otherwise approved by the Engineer. Approved deleterious materials (i.e., rock, shale, chert in limestone, other foreign material) and gradation proportions are as defined by the Engineer. c. Coarse and fine aggregates to include a maximum [ percent] passing the No. 200 for fine and coarse aggregate and maximum aggregate size not to exceed that of [Grade ] aggregate. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 4

5 4. Additives and admixture materials must be approved for use by CTS Cement Manufacturing Corp. prior to use. ( , B. Water: Clean, potable water free of deleterious amounts of silt and dissolved salts. 2.3 MIX DESIGN PROPERTIES A. Very Early High Strength, Low Shrinkage Hydraulic Cement Concrete 1. Provide Rapid Set [Low-P] [Low-P/FA1] Cement Concrete for the total concrete placement able to meet a minimum of 2,500 psi compressive strength at 3 hours in accordance with the following mix design. EDITOR NOTE: Modify below to suit project requirements. Minimum Cement Content Maximum Water Content 658 lbs. per cubic yard 19 gallons per cubic yard Coarse Aggregate 30-45% by weight of total aggregate Fine Aggregate Weight Ratio cement :fine aggregate: coarse aggregate W/C Actual (including estimated water from admixtures) 55-70% by weight of total aggregate 1.0 : 2.6 : 2.0 based on aggregate in a saturated surface dry condition 0.38 to 0.45 Air Content, % 0-6% Slump, in. Temperature, o F Ambient & Substrate 3 to 9 in. Minimum 45 o F and rising Maximum 90 o F Relative Yield 1.0 to 1.3 Chloride Permeability AASHTO T277 ASTM C1202 Compressive Strength Not greater than 1000 coulombs at 56 days Minimum 2,500 psi at 3 hours Minimum 3,500 psi at 1 day B. Any change in mix design or proportions must be approved by the Engineer. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 5

6 2.4 RELATED MATERIALS A. Admixtures: All additives and admixture materials must be approved for use by CTS Cement Manufacturing Corp. prior to use. ( , [1. Retarder/Set Control Admixture: Food grade citric acid. 2. Do not use additional fly ash or microsilica additives, pozzoloanic or Portland pozzolan materials. 3. Do not use admixtures containing calcium chloride. B. Consult with a qualified CTS Cement Technical Representative prior to the project if concrete will be pumped, used at temperature extremes, or when unusual job site conditions are anticipated. ( , PART 3 - EXECUTION 3.1 EXAMINATION A. Verify project site conditions under provisions of Section B. Compliance: Comply with manufacturer's instructions for installation of materials. C. Work must conform to all requirements of ACI Specification for Latex-Modified Concrete (LMC) Overlays except as modified by the Contract Documents. D. Coordinate installation with adjacent work to ensure proper sequencing of construction. E. Protect adjacent and surrounding surfaces not specified to receive concrete with necessary means to ensure protection against overspray, water or other harmful debris. F. Advise Contractor of discrepancies preventing proper installation of concrete materials. Do not proceed with the work until unsatisfactory conditions are corrected. 3.2 PREPARATION A. Follow guidelines provided in ACI 548.4, Section Surface Prep. B. For new and existing placements of Rapid Set [Low-P] [Low-P/FA1] Cement Concrete, clean the entire substrate thoroughly followed by oil-free air blast to remove any deleterious materials that could inhibit bond. C. Saw cut existing surface as detailed on plans and completely remove all loose materials. Use a jackhammer, chipping hammer or other suitable equipment to remove deteriorated concrete. Follow removal and preparation guidelines as directed by the Engineer. D. Clean all surfaces where concrete is to be placed using abrasive blasting or shot blasting equipment. E. Remove all loose, unsound, contaminated material to create a clean, sound surface free from any materials that may inhibit such as oil, dirt, paint, asphalt, sealing and curing compounds, acids, wax and loose dust and debris. F. Sound all exposed deck areas to identify unsound concrete. Remove any unsound concrete as necessary to ensure a successful overlay application. Comply with substrate bond requirements noted in ACI Guide for the Application of Epoxy and Latex Adhesives for Bonding Freshly Mixed and Hardened Concretes. G. Reinforcing steel must be free from rust and all other materials that may inhibit bond. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 6

7 EDITOR NOTE: Add special requirements related to the replacement of reinforcement that has lost too much cross sectional area. 3.3 MIXING H. Thoroughly saturate the area to receive concrete with water as soon as cleaning is complete. Keep thoroughly moistened until concrete is placed. Remove any standing water before material placement. I. Minimum substrate temperature must be 45 F (7 C) and maximum substrate temperature 90 F (32 C). A. Proportion and mix the Rapid Set [Low-P] [Low-P/FA1] Cement Concrete at the project site using a mobile, continuous, volumetric mixer or a weight batch mixer with a minimum capacity of six (6) cubic yards per hour. B. Comply with manufacturer s printed instructions and the following: 1. Organize installation personnel and equipment before mixing begins. 2. Prior to concrete placement, contractor must prepare trial batches of concrete for testing. Trial batches must comply with the limits specified. 3. The concrete discharged from the mixer must be uniform in composition and consistency. Mixing capability must be such that initial and final finishing operations can proceed at a steady pace. Final finishing must be completed before the formation of a plastic surface film on the surface. 4. The moisture content of aggregates at the time of proportioning must be such that water will not drain or drip from a sample. Coarse and fine aggregate must be furnished and handled to avoid variations in the moisture content affecting the uniform consistency of the concrete. 5. The water/cement ration must be within 0.02 of that specified in the approved mix design. If adjustments for water content beyond that are necessary, a previously tested and approved mixture must be used. 3.4 PLACING & FINISHING A. Comply with manufacturer s printed instructions and the following: 1. Verify that all substrates and ambient temperatures are between 45 F (7 C) to 90 F (32 C) and will remain within range until the concrete has reached final set. 2. Have all required tools, equipment and materials organized and as close to the placement area as possible. 3. Construct longitudinal stage joints at locations as shown on the plans or as approved. Construct a straight and vertical edge at longitudinal construction joints. 4. Moisten the prepared surface to a saturated surface dry condition just before placing the concrete. Remove standing water from the surface prior to placing the concrete. Cover with polyethylene sheeting until time of concrete placement. Surface must be damp at the time the overlay is placed. Any standing water in depressions, holes or areas of concrete removal must be blown out with compressed air. No free water or puddles of standing water shall exist at time of placement. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 7

8 5. Use bonding grout unless otherwise directed by the Engineer. Do not allow bonding grout to dry prior to placing Rapid Set [Low-P] [Low-P/FA1] Cement Concrete. 6. When bonding grout is required, scrub a thin coating of grout into the prepared surface immediately before placing the concrete. Ensure all surfaces, including vertical joints, receive a thorough, even coating and that no excess grout collects in pockets. Apply the grout so that it does not become dry before it is covered with concrete. 7. Place concrete continuously from one side of the application area across the shortest dimension. Minimize air entrapment. 8. Place and strike off the concrete to the final grade. Finish the surface with a float as necessary to produce a tight, uniform surface. 9. Expansion joints and dams must be formed in the concrete placement. Formation of the joint by sawing through the overlay will not be allowed. 10. Water must not be added to the surface of the concrete during finishing. Evaporation retardant may be used judiciously with a misting device during the finishing process until the wet burlap is applied only to prevent the surface of the concrete from drying out. The evaporation retardant must not be used to increase surface workability. 11. Ensure dense, watertight construction joints by properly consolidating the concrete and float-finishing the top surface of the joint flush with the adjacent concrete. 12. Texturing must occur immediately after finishing and before the plastic film forms on the surface. Texturing must be performed in a manner to prevent pulling the concrete away from an existing vertical face. Care must be taken not to texture too deep and not to tear the surface. 13. Screed rails and headers must be separated from the newly placed material by passing a pointing trowel along their inside face. Metal expansion dams must not be separated from new overlay. The trowel cut must be made for the entire depth and length of rails or headers after the mixture has stiffened sufficiently and must prevent the concrete from flowing back into the cut. 14. During placement, all joints with adjacent concrete must be treated and sealed as specified by the Engineer. 15. Concrete must be moist cured from the time placed until opened to traffic. Wet cure must be applied promptly after the concrete has been placed without deforming the finished surface. Within one hour of covering with wet burlap, a layer of white polyethylene sheeting must be placed on the wet burlap. Surface must receive a wet cure until the Rapid Set [Low-P] [Low-P/FA1] Cement Concrete has attained a compressive strength of at least 2,500 psi. 16. Thickness of the placement must be a minimum 1 inch and not exceed 3 inches unless otherwise approved by the Engineer. 17. After placement and curing, the finished deck will be tested to detect unbonded areas. Repair or replace as directed by the Engineer. B. Finishing Equipment 1. Use self-propelled rotating cylinder finishing machines with one or more rollers, capable of forward and reverse movement under positive control with a provision for raising all screeds to clear the screeded surface for traveling in reverse. Drag floats may be necessary. Any modifications must be approved by the Engineer. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 8

9 3.5 LIMITATIONS OF OPERATIONS A. No Rapid Set [Low-P] [Low-P/FA1] Cement Concrete should be placed with ambient or substrate surface is above 90 o F. Substrate temperature must be determined in accordance with the test method defined by the Engineer. B. Do not scarify, chip or otherwise mechanically treat surfaces within 6 feet of Rapid Set [Low-P] [Low-P/FA1] Cement Concrete overlay for at least 8 hours after placement. C. Rapid Set [Low-P] [Low-P/FA1] Cement Concrete may not exhibit bleed water making it susceptible to plastic shrinkage cracking. At surface evaporation rates above 0.1 pounds per square foot per hour, plastic shrinkage cracking is probable and the contractor should take precautions such as erecting windbreaks, lowering the mix temperature or delaying operations until ambient temperatures are lower. Surface evaporation rates can be predicted from mix temperature, air temperature, relative humidity and wind velocity using Figure 1 of ACI Standard Practice for Curing Concrete. 3.6 CURING A. Prevent rapid water loss from concrete during the first 3 hours by use of wet burlap. Wet-burlap cure the concrete as soon as possible. Keep the wet burlap on the placement until the concrete has reached the required strength. Cover the wet burlap with polyethylene sheeting to retain moisture. Use clean, potable water. 3.7 JOINT OPENING B. When the concrete header is used at an expansion joint location, remove the forming material placed between the two concrete headers prior to opening to traffic. 3.8 JOINT SEALANT A. After concrete has reached 2,500 psi compressive strength, prepare expansion joint surfaces to receive a joint sealant in accordance with the joint sealant requirements. 3.9 THOROUGHFARE OPENING A. Open the structure/placement area to normal construction traffic or traveling public when concrete has reached a minimum of 2,500 psi compressive strength at 3 hours after casting CLEAN-UP A. Remove and legally dispose of debris material from job site. B. Clean excess material from surrounding areas and all tools immediately, before material cures. If materials have cured, remove using mechanical methods that will not damage the application. C. Clean adjacent surfaces as needed using appropriate materials and methods to prevent damage to materials being cleaned. Remove and replace work that cannot be cleaned to the satisfaction of the Engineer or Owner. END OF SECTION Rev. July 2016 This sample guideline specification is intended for use by a qualified design professional. The sample guideline specification is not intended to be used verbatim as an actual specification without appropriate modifications for the specific project requirements. Rapid Set Very Early High Strength, Low Shrinkage, Powder Polymer-Modified Concrete Specification Page - 9