for Highway Construction Page 242 of 71 5 SECTION 409 – PORTLAND CEMENT CONCRETE PAVEMENT
409.01 Description.
Construct a portland cement concrete pavement as specified. Submit a proposed mix design. The Engineer will review the mix design for compliance with the specifications.
A.Classification . Proportion the materials for concrete to produce a workable concrete mix as specified in Table 409.01-1 . Table 409.01- 1 – Basic Mix Design Parameters Concrete Class in 100 psi (28 Day) (a) (b) (g) Minimum Cementitious Content lb/yd3 (c) (d) (e) (f) Water to Cement Ratio Slump in Air Content Percent 45 600 0.42 maximum 2 maximum 4 - 7
a.The class of concrete is the specified compressive strength when using the applicable tests as specified in 409.02.
b.A design value of 5,600 psi is specified to achieve the specified compressive strength.
c.Cement itious is cement plus secondary cementitious material (SCM).
d.It may not always be possible to produce concrete of the required strength using the minimum cementitious contents. No separate payment will be made by the Department for additional cementitious material required to meet specified strength.
e.Use SCM as specified in 714.
f.It may not always be possible to produce concrete using the minimum SCM content that will ensure mortar bar expansion does not ex ceed the standard limit when tested in accordance with CRD C 662 or ASTM C 1293. If additional SCM is needed to meet mortar bar expansion requirements, the Contractor may add it to the mix without a corresponding increase in cement provided the strength requirements are met. Obtain approval to add lithium or other mitigating measures to meet the mortar bar expansion requirement. A separate payment will not be made by the Department for additional cementitious material required to meet the specified compressive strength. The alkali content of the concrete must be kept below 3.0 lb/yd3 Na2Oe.
g.Concrete class designated as Class F will contain SCM. Minimum SCM content varies by product, for fly ash and slag cement (slag) minimum content is 20% by weight of total cementitious material. Fly ash will not exceed 25% of total cementitious material. Slag will not exceed 35% of the total cementitious material. Ternary and quaternary blends will contain at least 20% SCM. Total SCM content will not exceed 50%.
B.Acceptance. Concrete acceptance is based on compliance with parameters specified for paving concrete. Strength is accepted based on the results of the 28- day compressive strength tests determined in accordance with AASHTO T 22. The average strength of 3 companion cylinders is 1 test. When the 28- day strength for a test falls below the specified strength, concrete represented by that test is subject to rejection or a price adjustment . The Engineer may accept paving concrete at a reduced price, if the strength is within 10 percent of the spec ified strength. Concrete represented by tests more than 10 percent below specified strength is subject to rejection. Remove unacceptable concrete at no additional cost to the Department. The Engineer will use Table 409.01- 2 to determine the unit price adjustment of failing paving concrete allowed to remain in place. for Highway Construction Page 243 of 71 5 Table 409.01-2 – Unit Price Adjustment Percent of Specified Strength Pay Factor ≥ 100 1 ≥ 95 < 100 0.9 ≥ 90 < 95 0.8 < 90 Subject to rejection (a)
a.If allowed to remain in place, the pay factor will be 0.50. The Department will pay for the accepted concrete quantity at the contract unit price multiplied by the price adjustment pay factor as determined from Table 409.01 -2. Core drilling, at no additional cost to the Department, is an acceptable alternative test to dispute test results for concrete subject to price adjustment or rejection. The Engineer will determine the location and number of cores and witness coring and test ing. Repair holes left by the coring operation at no additional cost to t he Department. Obtain approval for repair methods and materials before beginning repairs . Cores obtained within 42 calendar days of the time of placement will be considered by the Department as representing the 28- day strength. Cores obtained after 42 calendar days will only be acceptable to the Engineer when the Contractor submits a correlation curve developed by a Department approved independent testing laboratory to relate strength at the actual test age to 28- day strength for the particular class and design mix represented by the cores. The Department and the Contractor agree to accept the results of the tests of the drilled cores instead of the results of the test cylinders when drilled cores are approved as the method of determining strength. Obtain and test cores in accordance with AASHTO T 24 with the following exceptions:
1.Protect cores from moisture gain or loss.
2.Test as soon as possible without further conditioning other than preparation of the ends, if needed. Take at least 3 representative cores from each area of in- place concrete that is considered potentially deficient. Replace cores that show evidence of damage during coring or removal with a new core bef ore testing . Tests performed by an approved independent testing laboratory on cores taken from the work may include compressive strength, cement content determined by ASTM C1084, and petrographic analysis determined by ASTM C856, including water cement ratio and air content. Remove concrete represented by cores with an average strength less than the specified strength, unless accepted at a reduced price by the Engineer. Make corrective changes in the materials mix portions, concrete fabrication procedures, or other corrective action before continuing to use concrete that does not comply with the specified compressive strength, at no additional cost to the Department. If results of 7- day st rength tests are low or show a downward trend, predicting concrete may not meet the specified 28- day strength, make corrective changes. Changes are subject to approval . for Highway Construction Page 244 of 71 5 409.02 Materials. Provide materials as specified: Portland Cement ........................................................................................................................... 701 Aggregate ..................................................................................................................................... 703 Joint Filler s and Sealers ............................................................................................................... 704 Silicone Joint Sealant .............................................................................................................. 704.05 Reinforcing Steel ..................................................................................................................... 708.02 Dowel Bars ................................................................................................................... 576 or 708.03 Tie Bars ................................................................................................................................... 708.04 Membra ne-Forming Curing Compound, System 2 .................................................................. 709.01 Air-Entraining Admixtures ........................................................................................................ 709.03 Set Retarding Admixtures ........................................................................................................ 709.04 Water -Reducing Admixtures .................................................................................................... 709.05 Lithium Nitrate Admixtures ....................................................................................................... 709.06 Secondary Cementitious Materials ............................................................................................... 714 Water ....................................................................................................................................... 720.01 Epoxy - Resin - Base Bonding Systems .................................................................................... 720.04 If it is determined that concrete aggregate is reactive for ASR according to 703.02, test the concrete mix for effectiveness of mitigation measures using CRD C662 (Table 502.02- 1) or ASTM C1293 (Table 502.02 -2). All results must be provided with the mix design submittal . Table 409.02 -1 - Characterizing Effectiveness of Mitigation in Concrete (CRD C 662 ) Expansion at 28 days (%) Characterization Min Max 0 0.09 Acceptable 0.10 0.14 Uncertaina 0.15 N/A Not effectivea a: Redesign until concrete mix meets acceptable expansion limits Table 409.02 -2 - Characterizing Effectiveness of Mitigation in Concrete (ASTM C 1293 ) Expansion at 2 years (%) Characterization Min Max 0 0.039 Acceptable 0.040 N/A Not effective for Highway Construction Page 245 of 715 Obtain approval of admixtures before use. Determine an aggregate correction factor in accordance with AASHTO T 152 and submit with each mix design . Test in accordance with the following standard methods: Compressive Strength of Cylindrical Concrete Specimens .......................................... AASHTO T 22 Making and Curing Concrete Test Specimens in the Field (Use 6 inch diameter by 12 inch single use molds made of plastic.) ..................... AASHTO T 23 Obtaining and Testing Drilled Cores and Sawed Beams of Concrete (Provisions of AASHTO T 24 relating to ASTM and American Concrete Institute (ACI) references do not apply) ....................................................................................... AASHTO T 24 Slump of Hydraulic Cement Concrete ....................................................................... AASHTO T 119 Mass Per Cubic Foot (Cubic Meter), Yield, and Air Content (Gravimetric) of Concrete Including Cement Content ................................................................................... AASHTO T 121 Making and Curing Concrete Test Specimens in the Laboratory (Use 6 inch diameter by 12 inch single use molds made of plastic.) ..................... AASHTO R 39 Measuring Length of Drilled Concrete Cores ............................................................. AASHTO T 148 Air Content of F reshly Mixed Concrete by the Pressure Method .............................. AASHTO T 152 Measuring Texture Depth of Portland Cement Concrete Using a Tire Tread Depth Gauge ............................................................................ Idaho IT 147 Pavement Straightedge Pr ocedures ................................................................................. Idaho IT 87 Standard Practice for Operating an Inertial Profiler System ........................................ AASHTO R 57 Method of Testing Thickness of Plastic Concrete Pavement ......................................... Idaho IT 130 Determination of the Rate of Evaporation of Subsurface Moisture from Concrete ..................................................................... Idaho IT 133 Determining the Percentage of Fracture of Coarse Aggregate .......................................................... AASHTO T 33 5 Method 1 Sampling Freshly Mixed Concrete ................................................................................ WAQTC TM 2 Temperature of Freshly Mixed Portland Cement Concrete ........................................ AASHTO T 309 Determining the Potential Alkali Silica Reactivity of Combinations of Cement itious Materials, Lithium Nitrate Admixture and Aggregate (Accelerated Mortar -Bar Method) ..................................................... CRD- C 662 Standard Test Method for Static Modulus of Elasticity and for Highway Construction Page 246 of 71 5 Poisson’s Ratio of Concrete in Compression ........................................................... ASTM C469 Standard Test Method for Length Change of Hardened Hydraulic Cement for Mortar and Concrete ................................................................................................. ASTM C157 Standard Practice for Petrographic Examination of Hardened Concrete ......................... ASTM C856 Standard Practice for Estimating Concrete Strength by the Maturity Method ...................................................................................................... ASTM C1074 Standard Test Method for Portland- Cement Content of Hardened Hydraulic -Cement Concrete .................................................................................... ASTM C1084 Time of Setting of Concrete Mixtures by Penetration Resistance .............................. AASHTO T 197 Standar d Method of Test for Determining the Percentage of Fracture in Coarse Aggregate .............................................................. AASHTO T 335 Method 1 Coefficient of Thermal Expansion of Hydraulic Cement Concrete ............................ .AASHTO T 336 Standard Method of Test for Surface Resistivity Indication of Concrete 's Ability to Resist Chloride Ion Penetration .......................................... AASHTO T 358 Standard Method of Test for Pavement Thickness by Magnetic Pulse Induction ................................................................................................... AASHTO T 359 Standard Method of Test for Potential Alkali Reactivity of Aggregates and Effectiveness of ASR Mitigation Measures ................................................... AASHTO T 380 Standard Test Method for Determination of Length Change of Concrete Due to Alkali- Silica Reaction ................................................................................... ASTM C1293 Standard Test Method for Measuring the Longitudinal Profile of Traveled Surfaces with an Accelerometer -Established Inertial Profiling Reference ................. ASTM E950
409.03 Construction Requirements.
A.Proportioning. The concrete mix design is the Contractor’s responsibility and includes making and testing compressive strength specimens. Make and test compressive strength specimens using the Contractor’s laboratory or a Department -approved independent laboratory. Uniquely identify each mix design submitted. For work exceeding 2,500 cubic yards, submit the following at least 60 calendar days before proposed use:
1.The proposed mix design.
2.Copies of test reports.
3.Data.
4.Worksheets.
5.Samples of the proposed aggregate, cement, SCM, and admixtures . for Highway Construction Page 247 of 715 6. "Final set" time with the mix design as measured using AASHTO T 197M / T 197.
7.Mixing water source.
8.Proposed curing compound.
9.Theoretical maximum density.
10.Rate of development of electrical resistivity to 28 calendar days.
11.Modulus of elasticity at 28 calendar days.
12.Drying shrinkage.
13.Coefficient of thermal expansion. Do not produce concrete until the mix design is approved by the Central Materials Laboratory . For work less than 2,500 cubic yards, submit the following at least 14 calendar days before proposed use:
1.The proposed mix design.
2.Copies of test reports.
3.Data.
4.Worksheets.
5."Final set" time with the mix design as measured using AASHTO T 197M / T 197.
6.Mixing water source.
7.Proposed curing compound.
8.Theoretical maximum density.
9.Rate of development of electrical resistivity to 28 calendar days.
10.Modulus of elasticity at 28 calendar days.
11.Drying shrinkage.
12.Coefficient of thermal expansion. Do not produce concrete until the mix design is approved. Limit the fine aggregate by weight of total aggregate to 40 percent in the proposed mix designs. Use only angular coarse aggregate . Angular aggregate is defined as having greater than 40 percent fractured faces. The Department will base fracture on the aggregate particles retained on the No. 4 sieve with 1 or more fractured faces as determined by AASHTO T 335 Method 1. The minimum mix design compressive strength is 5,600 psi when tested at 28 calendar days and is determined from the average of 3 specimens produced and cured in the laboratory. In addition to strength, report the air content and slump. Strength data is valid only if air content, slump, and water -cement ratios are within the required limits for the specified mix class. CRD- C 662CRD- C 662Use number 4 coarse aggregate . Establish the exact proportions from trial mixes from the materials to be used in the work and make adjustments to use the least amount of sand necessary to produce concrete with the required workability and strength. for Highway Construction Page 248 of 71 5 At the Contractor’s option, a combined gradation number 4C may be used. Design the proposed mix using the KU Mix Program from the University of Kansas and submit for approval. Include documentation and worksheets i n the submittal . Base the combined gradation and sand equivalent on the average of the stockpile as determined by the production quality control tests. Submit quality control charts and tests wi th the mix design. The Contractor may reduce minimum cementitious material contents by 20 percent if a combined gradation is used. If the contract does not require SCM, the Contractor may submit a mix design subject to the same requirements as if the contract requires SCM. Do not vary calcium oxide (CaO) content more than 2 percent above that used for AASHTO T 380 testing where fly ash is used in the concrete m ix for ASR mitigation. If the fly ash has a CaO content greater than 2 percent above the fly ash used for testing, additional AASHTO T 380 testing at the higher CaO content is required by the Department. Wherever SCM are is used, use the same SCM source, c ement source (mill), and cement type throughout the work for each mix design. Submit lab test reports to verify the revised mix design meets specification requirements. A 3.5 inch maximum slump is allowed for hand finishing if a sl ipform concrete paver is not used to construct concrete pavement . A 4.5 inch maximum slump and a 5 percent reduction in 28- day compressive strength is permissible for concrete media ns and other nontraveled surfaces, excluding shoulders.
B.Equipment.
1.Mixers and Hauling Equipment .
a.Mixers, agitators and nonagitating hauling equipment . Mixers may be stationary mixers or truck mixers. A gitators may be truck mixers or truck agitators. Equip truck mixers and agitators with an accessible revolution counter for the drum, blades, or paddles to verify revolutions. Ensure a NRMCA standard metal plate or plates are attached to each mixer and agitator by the manufacturer and plainly marked with the various uses for which the equipment is designed, the volume of the drum, the capacity of the drum or container in terms of the volume of mixed concrete , and the speed of rotation of the mixing drum or blades. Equip stationary mixers with an acceptable timing device that will prevent discharge until the specified mixing time has elapsed. Equip truck mixers with a calibrated water flow meter or other approved measuring device to control the quantity of mixing water added in the field.
b.Provide mixers that, when loaded to the rated mixing capacity and the concrete is mixed for the time or revolutions prescribed, combine the ingredients of the concrete into a thoroughly mixed uniform mass and discharge the concrete with satisfactory uniformity as specified in 409.03.D.
c.Provide agitators that maintain the mixed concrete in a thoroughly mixed and uniform mass and are capable of discharging the concrete with a satisfactory degree of uniformity when loaded to rated capacity as specified in 409.03.D.
d.Provide nonagitating equipment with bodies that are smooth, mortar -tight metal containers capable of discharging the concrete without segregation .
2.Paving Equipment. Construct pavement using paving equipment that uniformly spreads at the proper thicknes s for the width of the area being paved, consolidates the freshly placed concrete and produces a finished surface meeting straightedge and profile index requirements of 409.03.K, for Highway Construction Page 249 of 71 5 before grinding. If the pavement produced does not meet these requirements, suspend concrete paving operations until the deficiencies or malfunction is corrected. Use self -propelled paving machines that comply with the following:
a.Placer/Spreader: Receive the concrete mixture into hopper(s) adjac ent to the area to be paved.
b.Slipform paver: Equipped with automatic screed control mechanisms that operate from stringlines erected near the right and left side of the machine. Check the depth of placement at 50 feet i ntervals to achieve the design thickness between the outside edges after the stringlines are established. Consolidate the concrete with internal vibrators. Limit the rate of vibration to less than 3,500 vibrations per minute for surface vibrators and 8,000 to 12,000 vibrations per minute for internal vibrators. Provide a tachometer or other suitable device for measuring and indicating the actual frequency of vibrations. Do not rest vibrators on new pavements or side forms . Con nect power to the vibrators so the vibration will stop when the forward or backward motion of the machine is stopped.
c.Machine Paving with Forms: The Contractor may finish concrete pavement in sm all irregular areas as specified in 411.03.B instead of using slipform pavers, when approved.
d.Bridge Deck Machine: The Contractor may finish concrete pavement in small irregular areas with a concrete bridge deck finishing machine as specified in 502.03 instead of using slipform pavers, when approved. Finishing and surface test specifications apply.
3.Concrete Sawin g Equipment. Provide at least 3 production saws, including 1 standby unit, adequately powered to perform the work. Provide saws that are multiple arbor or multiple blade gang saws. Mount saws operating on 3 to 4- hour old, nonrigid pavement on a work bridge so the machine weight is not placed on the new concrete. Provide adequate artificial lighting for night sawing. Maintain equipment in good working order and have it on the job before the first placement and continuously during concrete paving operations. Maintain an ample supply of saw blades during the sawing operations. Do not pave until concrete sawing equipment is onsite and ready for use.
C.Handling, Measuring, and Batching Materials . Produce concrete that meets the approved mix design. Submit the proportioned ingredients for each batch. Request changes to the mix design and obtain approval from the Engineer for a new mix design befor e batching concrete. Minor adjustments due to varying moisture in the aggregates, changes in aggregate gradation when using a combined gradation, and minor adjustments of approved admixtures are not considered changes in the mix design and will not require another approval. Report the minor mix adjustments in writing to the Engineer before batching.
1.Measure cement by weight. Weigh cement in an individual hopper and keep separate from the aggregates until released for discharge. Attach the cement hopper to a separate scale for individual weighing or to the aggregate scale for cumulative weighing. Weigh cement before adding the other ingredients, if weighing cumulatively. Use a cement scale and weigh hopper that is separate and distinct from the aggregate weighing equipment. Provide cement batchers with a dust seal between the charging mechanism and hopper. Install the dust seal so it does not affect the for Highway Construction Page 250 of 715 weighi ng accuracy and is vented to allow the escape of air. Provide a self -cleaning hopper fitted with a means to ensure complete discharge . Provide sufficient wind protection to prevent interference with batching accuracy. Ensure the cement, as weighed, is within 1 percent of the design weight.
2.Measure aggregates by weight. Weigh individual aggregates within two percent of the required weights and the total weight of the aggregate within 2 percent of the total required weight. Handle aggregates from stockpiles or other sources to the batching plant so uniform grading and stable moisture content is maintained. Stockpile or bin aggregates to drain for at least 12 hours before batching aggregates produced or handled by hydrauli c methods or washed aggregates. Verify aggregate gradation meets the requirements for the proposed mix design.
3.Measure water by volume or by weight. Arrange the measuring device so the measurements will not be affected by variable pressures in the water supply line. Do not use wash water as a portion of the mixing water. Weigh or measure water within 1 percent of the required amount.
4.Measure SCM by weigh t. Weigh the SCM within 1 percent of the design weight.
5.Measur e dry admixtures by weight and paste or liquid admixtures by weight or volume. Dispense admixtures used in small quantities in proportion to the cement, as air -entraining admixtures, with the mixing wate r. Adjust the quantity of admixtures used in accordance with manufacturer’s written instructions. Use admixtures that meet 709.02 .
D.Mixing and Delivering .
1.Mix and deliver concrete by any of the following means:
a.Central mixed concrete. Mix completely in a stationary mixer and transport the mixed concrete to the point of delivery in agitating equipment or in approved nonagitating equipment.
b.Transit mixed concrete . Mix completely in a truck mixer at the batching plant or while in transit.
c.Truck mixed concrete. Mix completely in a truck mixer at the point of delivery after adding mixing water.
d.Shrink mixed concrete . Mix partially in a stationary mixer and complete the mixing in a truck mixer.
e.Mix in an approved mixer that volumetricall y measures the concrete ingredients and continuously produces concrete that meets the requirements of ASTM C685.
2.Operate truck mixers and truck agitator s within the rated capacity, and at a speed of rotation for mixing or agitating, as designated by the equipment manufacturer.
3.The minimum mixing time for mixers of 10 cubic yards or less capacity is 50 seconds when a stationary mixer is used for the complete concrete mixing. Obtain approval of the mixing time for mixers of 10 cubic yards or more capacity. Measure mixing t ime from the time cement and aggregates are in the drum. Charge the batch into the mixer so some water will enter bef ore cement and aggregates, and water is in the drum by the end of the first ¼ of the specified mixing time.
4.The Contractor may reduce the mixing time in the stationary mixer at least 30 seconds for shrink mixed concrete. Complete the mixing in a truck mixer with between 50 and 100 revolutions of the for Highway Construction Page 251 of 715 drum or b lades at mixing speed. Do not exceed a batch volume of 70 percent of the drum gross volume.
5.When a truck mixer is used for complete mixing, mix each batch of concrete with between 70 and 100 revolutions of the drum or blades at mixing speed. Use agitating speed for additional revolutions.
6.When a truck mixer or agitator is used for transporting concrete completely mixed in a stationary mixer, use agitating speed for mixing during transport.
7.When a truck mixer or agitator is used for transporting concrete , apply the following:
a.Deliver the concrete to the project site and complete discharge within 1.5 hours after the introduction of the cement to the aggregates or before the drum has revolved 300 revolutions, whichever comes f irst.
b.In hot weather, or under conditions contributing to quick stiffening of the concrete, a time less than 1.5 hours may be necessary.
c.Begin the mixing operation within 30 minutes after the cement has been intermingl ed with the aggregates when a truck mixer is used for the complete mixing of the concrete.
d.If additional mixing water is approved, at least 30 additional revolutions of the truck mixer drum at mixing speed are required before discharge of concrete. T he Engineer may allow mixing water only 1 time during the discharge of the concrete.
e.The Engineer may require tests for consistency at approximately the beginning, the midpoint, and the end of the load. If the results vary by more than 1 inch, do not us e the mixer or agitator until the condition is corrected.
8.Transport central mixed concrete in suitable nonagitating equipment. Provide covers when specified. Equip bodies with smooth, mortar -tight metal cont ainers capable of discharging the concrete at a controlled rate without segregation. Completely discharge concrete within 45 minutes after the introduction of the cement to the aggregates.
9.Do not use aluminum pipe or aluminum truck beds to convey concrete .
10.Provide concrete at a temperature of at least 50°F and not more than 85°F at the time of placing.
E.Conditioning of Subgrade or Base Course . Check the base or subgrade surface and correct deficiencies before placing concrete. Place concrete pavement on the uniformly moistened surface of the completed base or subgrade. Moisten asphalt -treated base surfaces immediately ahead of the placement of concrete pavement to ensure compliance with temperature requirements. Remove excess moisture before paving.
F.Temperature Limitations . Place concrete pavement with the following precautions:
1.During cold weather, when ambient temperature falls below 40°F, produce mixed concrete with a temperature at least 50°F and less than 85°F at the time of placing. The water and/or the aggregate may need t o be heated to a temperature of between 70°F and 150°F. The Contractor may place concrete pavement when the air temperature is below 40°F as specified in 409.03.M. for Highway Construction Page 252 of 71 5 2. Do not place concrete on frozen subgrade or use frozen aggregates in the concrete.
3.Do not place concrete if the concrete temperature is greater than 85°F at time of placement . Do not place concrete when the evaporation rate is greater than 0.15 pounds per square foot per hour when tested in accordance with Idaho IT 133. Night or early morning placement may be necessary to avoid excess evaporation. Ice used as a part of the mixing water must be completely melted by the time mixing is completed.
4.Do not place concrete on a surface with a temperature exceeding 90°F.
G.Hand Placing Concrete . The following conditions allow hand placing and finishing methods:
1.Breakdown of the mechanical equipment when the concrete is already deposited on the grade.
2.Narrow widths or areas of irregular dimensions where operating mechanical equipment is impractical. Obtain approval before placing concrete in wood or metal forms .
3.Do the following when hand placing and finishing methods are allowed:
a.Place a test section to show the proposed operation is capable of satisfactorily consolidating and striking off the concrete to the required grade, section, and applicable smoothness requirements when Engineer requested.
b.Spread concrete evenly. Do not use vibrators for extensive shifting of the concrete mass. Us e surface vibrators, internal vibrators, or other methods that produce equivalent results without segregation to consolidate concrete. Thoroughly consolidate concrete against and along forms or adjoining pavement so gravel pockets along the edges of the finished pavement are prevented. Repair gravel pockets found after removing the forms. Consolidate uniformly across the full pavement width. Strike off the concrete to the intended surface profile after cons olidation.
c.Provide a screed at least 2 feet longer than the maximum width of the slab to be struck off. Use a screed constructed of metal or other suitable material clad with metal, rigid enough to keep its shape, and is approved.
d.Move the screed forward on the forms with a combined longitudinal and transverse shearing motion, always moving in the direction in which the work is progressing, and manipulated so neither end is raised from the side forms during the stri king off process. Repeat until the surface has uniform texture, is true to grade and cross -section, and has no porous areas, if necessary.
e.Smooth the concrete by floating after it has been consolidated and struck off. Do not float concr ete within 3 0 feet of consolidation and strike off. The Contractor may use long handled floats having blades at least 4 feet in length to smooth and fill in open textured areas in the pavement . The Contractor may use a full width float. Move ahead in successive advances of not more than one- half the length of the float. Continue floating until irregularities are removed. Remove free water on the pavement with the float or other suitable tool.
f.Float the surface transversely using a long h andled float when the crown of the pavement will not allow using a longitudinal float. Do not work the crown out of the pavement.
g.Remove excess water and laitance from the pavement surface after floating. Use a straight edge at least 10 feet long with a long handle for operating at the edge of the pavement. Lap successive drags ½ the length of the blade. for Highway Construction Page 253 of 71 5 h. Finish the surface of the concrete pavement as specified in 409.03.J. Us e hand methods that result in the finish as specified in 409.03.J when a self -propelled comb is not practical.
i.Smoothness requirements apply.
j.Do not place additional water on the concrete surface during the machine or hand finish opera tion.
H.Joints . Construct joints as specified. Use suitable guidelines or devices to ensure sawing the joints at the proper location.
1.Stress Relief Joint Sawing. Make the initial stress relief saw cuts, to control shr inkage cracking, as soon as the concrete has hardened enough to allow sawing without raveling. Saw to the depth, width, line, and spacing as specified. Continue stress relief sawing operations at night or under inclement weather conditions as required. Keep the sawing operation up to pace with the paving operation; otherwise stop paving work until the sawing operation can keep pace with the paving operation. Single cut stress relief joints will be ¼ inch wid e and will be saw cut to 1/3 depth of the concrete pavement. Single cut stress relief joints will be sealed with a hot poured elastomeric joint filler meeting the requirements of 704.03. Backer rods will not be used. When a single saw cut joint is specified, thoroughly clean the sides of the joint and the adjacent pavement surface, approximately 1 inch on each side of the joint, of scale, dirt, dust, and other foreign material by jet water bl asting immediately after sawing. Remove the residue from sawing and water blasting from the pavement surface before it is blown by traffic or wind. Prevent the residue from entering lanes used by traffic.
2.Sealant Reservoir Construction. Allow the concrete to cure at least 72 hours and then saw the joints to the width and depth as specified to accommodate sealant placement, when a sealant reservoir is specified. Do not saw wider than speci fied. Thoroughly clean the sides of the sealant reservoir and adjacent pavement surface, approximately 1 inch on each side of the joint, of scale, dirt, dust, and other foreign material by jet water blasting immediately af ter sawing. Remove the residue from sawing and water blasting from the pavement surface before it is blown by traffic or wind. Prevent the residue from entering lanes used by traffic. Repair damage (e.g., spalling, fracturing) to the concrete pavement . Properly cure repairs before installing the joint sealant.
3.Tie Bars. Place deformed tie bars of the specified length, size, and material. Place tie bars using approved mechanical equipment, rigidly secured by chairs or other supports to prevent displacement. Do not treat the tie bars; this will impair bonding with the concrete. Locate tie bar within tolerances as specified or as directed.
4.Load T ransfer Devices. Incorporate load transfer devices into the concrete pavement by using dowel bar assemblies or dowel bar inserters.
a.Dowel Bar Assemblies .
1.Fabrication. Fab ricate dowel bar assemblies, or baskets, in single units for appropriate lanes before being placed on grade. Submit material detail sheets with basket size and complete anchoring details for approval. for Highway Construction Page 254 of 71 5 (2) Anchoring. Securely anchor dowel bar assemblies at grade to prevent displacement during concrete paving. Secure baskets with at least 8 pins to ensure they hold bars within tolerance. The Engineer will check dow el basket placement and anchorage before concrete placement. Cover dowel bar assemblies with fresh concrete immediately ahead of the paver . Properly realign and re- anchor any dowel baskets removed to accommodate delivery of concrete before the paver arrival.
3.Location. Check and document dowel bar location at least every 30 joints after placement of concrete. Locate the baskets and dowels in plastic concrete with a hand tr owel, or other approved method, to verify location and accuracy. Note and mark the joint locations that are not acceptable and take action to determine and correct the deficiencies ahead of the paver .
4.Dowel Bars . Coat d owel bars in accordance with AASHTO M 254 Type A or B. Give Type B dowel bars in assemblies a thin coating of graphite grease, or approved equal, as a bond breaker. On ramps, tapers, and widenings, use less than 2 assembly sections in a joint.
b.Dowel Bar Inserters. As an alternative to dowel bar assemblies on grade, the Contractor may insert dowel bars into the plastic concrete by an approved mechanical device that ensures reconsolidation around the bars. Place the bars parallel to the pavement centerline and surface. Insert the bars before the passage of the final finishing beam or screed.
1.Approval. Do not use dowel bar inserters without prior Engineer approval. Use an approved method to detect and verify the location of dowel bars .
2.Location. Use ground penetrating radar (GPR), magnetic tomography (MIT -scan), pacometer, or other approved device to establish the location and to ensure compliance with the tolerances of the dowel bar placement of at least 10 percent of the joints . The Engineer will select the joints to be inspected at random. Take at least 2 cores to verify the calibration of the insertion equipment. When inspection shows dowel bars out of tolerance, inspect remaining joints with the approved device. Repair holes left in the pavement by the coring operation at n o additional cost to the Department. Obtain approval for repair methods and materials bef ore beginning repairs .
3.Dowel Bars . Coat dowel bars in accordance with AASHTO M 254 Type A or B. Give Type B dowel bars to be inserted a 2 layer bond breaker coating. Use an approved dry film (e.g., 3M™ PT FE) on the first layer. Apply a thin layer of form oil over the dry film. Use extra precautions to prevent form oil runoff from contaminating the fresh concrete. Locate load transfer devices within tolerances as specified or as directed regardless of method of incorporation. Dowel bars, whether placed in baskets or inserted, must have at least 6 inches of bar embedded in each slab. Retrofit missing dowels, or dowels out of tolerance in the wheel path area. The Engineer may accept payment in place of retrofitting bars in areas outside of the wheel path. As payment, missing dowel bars will be charged by the Department to the Contractor at the cost to retrofit the bars into the slabs. for Highway Construction Page 255 of 715 Provide positive control and an approved method of marking dowel bar locations for correlation to sawed joints . Dowels are r equired where the new concrete pavement abuts the existing concrete pavement . Drill holes into the existing concrete pavement as specified or as directed and epoxy grout dowel bars into the holes. Obtain approval of epoxy grout bef ore use.
5.Construction Joints . Place construction joints at right angles to the centerline when there is an interruption of more than 45 minutes in the conc rete paving operations. Do not place transverse joints closer than 6 feet apart. Place the construction joint at the same location as would be used for a transverse joint whenever possible.
6.Random Cracks. After sawing i s completed, remove random cracks penetrating the full depth of the pavement , whether transverse or longitudinal, by replacing the cracked slabs. Remove and replace cracked slabs at no additional cost to the Department.
I.Tolerance in Pavement Thickness. Construct pavement as specified. The pavement thickness is subject to price adjustment in accordance with Table 409.05- 1. Once the pavement is sufficiently cured to support foot traffic, the Engineer will check the completed pavement thickness of the concrete by measuring the distance from the concrete pavement surface to the underlying surface in accordance with FOP for AASHTO T 359. Provide five 2 inch diameter cores for verification of the depth, as directed. The Contractor may take cores, as approved, to dispute depth measurements taken by the Engineer. The Engineer will witness the coring. Core, test, and repair the concrete pavement at no additional cost to the Department. The E ngineer will determine pavement thickness by average depth measurements in accordance with FOP for AASHTO T 359. An adjusted unit price for pavement is defined as a single placement width 0.1 mile long. The Engineer will determine the average thickness of the pavement in accordance with FOP for AASHTO T 359 calculated as follows:
1.When the thickness is more or less than 0.1 inch of the specified thickness, but less than 0.5 inch, that section is eligible for an incentive or disincentive price adjustment as specified in Table
409.05 1.
2.When the thickness is more than the target range of the specified thickness, no price adjustment will be made by the Engineer for the concrete left in place.
3.The average thickness applies for each section individually. The Engineer will calculate thic kness incentive or disincentive by comparin g the measured average thickness to the plan thickness for the concrete paving. The Department will make an adjusted payment for the test section in accordance wi th Table 409.05- 1. Each depth measurement set represents the pavement thickness for a 0.1 mile segment, or in the case of a beginning or ending measurement, the distance will extend to the end of the pavement section. for Highway Construction Page 256 of 715 J. Final Finish. Finish the surface of the concrete pavement by tining and use a self -propelled steel comb. Tining will be specified as longitudinal or transverse. Provide longitudinal tining if the method is not specified.
1.Gener al. Give the pavement an init ial and a final texturing before the curing operations. Perform the initial texturing with a burlap drag or broom device that will produce striations parallel with centerline. Use burlap that is a coarse fabric of jute or hemp. Use a single piece burlap drag extending the entire width of the paving operations. Install burlap drags, brooms, and tine devices on self -propelled equipment having external alignment control. Maintain a constant area of burlap in contact with the pavem ent surface when texturing. Replace the burlap drag whenever results are unacceptable to the Engineer. Provide broom and tine devices with positive elevation control. Maintain downward pressure on the pavement surface during operation to achieve uniform texturing without measurable variations in pavement profile. Operate the self -propelled texturing machines at a constant travel speed that keeps pace with paving operations. Stop placing the conc rete when the finishing equipment does not comply with these provisions. Resume when the equipment deficiency or malfunction is corrected. Use spring steel tines on the final texturing device that have a rectangular cros s-section 1/8 inch wide, on 3/4 inch cen ters, and whose length, thickness, and resilience will form grooves approximately 3/16 inch deep in the fresh concrete surface. Form the grooves in the plastic concrete without tearing the surface and without bringing pieces of the coarse aggregate to the top of the surface. Produce a final texture with a uniform appearance with the grooves having a depth 5/32 inch ± 1/32 inch. Maintain a 1- inch gap between each tine strip to prevent overlapping the tined surface and producing a weak surface area. Measure the groove depth in accordance with Idaho IT 147. Make adjustments to the tining operation when more than 3 readings in a set of 10 are outside the intended depth range. Round t he edges of the pavem ent along each side of each slab and on each side of transverse expansion joints , formed joints, and construction joints, to a radius of 1/8 inch before the concrete has taken its initial set. Produce a well -defined and continuous radius and a smooth dense mortar finish. Do not unduly disturb the surface of the slab by tilting the tool during use. Eliminate tool marks appearing on the slab adjacent to the joints . In doing this, d o not disturb the rounding of the corner of the slab. Completely remove concrete on top of the joint filler . Test joints with a straightedge before the concrete has set. Make correction if one side of the joint is higher than the other or if they are higher or lower than the adjacent slabs. Correct areas of concrete pavement that are not finished as specified in these requir ements by retexturing. The Contractor may retexture by cutting transverse grooves in the concrete pavement surface by means of saw blades or other approved devices. Space the grooves 3/4 inch center to center and 1/8 inch in width and depth. Obtain approval to use alternative patterns. Do not polish the concrete pavement surface after cutting.
2.Longitudinal Tining. Perform final texturing with a spring steel tine device that will produce grooves parallel with the centerline. for Highway Construction Page 257 of 71 5 Tine the concrete surface within 5 inches, but not closer than 3 inches, of longitudinal pavement edges and formed joints .
3.Transverse Tining. Perform final texturing with a spring steel tine device that will produce grooves parallel to the transverse joints or perpendicular to the centerline. Repeat the grooving pattern across the pavement . Secure the tines of a double tine comb together. Do not use the comb within 1 foot of either edge when the finishing machine causes edge slump. Comb these unfinished edges by hand.
K.Surface Test. Test the finished pavement the next working day after placement as follows :
1.Use a 10- foot straightedge on the surface at locations determined by the Engineer. When the straightedge is laid on finished pavement in a direction parallel with centerline or perpendicular to centerline, locate surface areas that vary more than 1/4 inch from the lower edge. Remove high points that cause the surface to exceed these tolerances by grinding.
2.Furnish and operate the profiler. Operate the profiler at the manufacturer’s recommended speed. Calibrate at the beginning of the work and as needed thereafter. Supply a profiler, calibrated, in good working condition, and ready for operation before work of any concrete paving begins. Provide a competent and experienced operator to operate the equipment. Profile th e surface in IRI. Make 2 profiles 3 feet from and parallel to the edge of each driving lane. Surface smoothness testing must be verified by the Engineer. The profile run must be witnessed by the Engineer and an el ectronic copy of the results submitted immediately after the end of the run. Testing will not be accepted unless witnessed by the Engineer. At the Engineer’s request, submit the profile data in a format suitable for evaluation using ProVAL or other acceptable software. The Engineer may elect to perform additional testing as verification. If the results vary from the Contractor’s IRI results by more than 10 percent when profiled under the same environmental conditions, the Engineer will use the Department’s IRI results for acceptance. Use Class 1 or Cla ss 2 profilers as defined by ASTM E950. Operate profilers in accordance with the manufacturer’s instructions and AASHTO R 57. Set the profiler as follows:
a.High pass or pre- filter: off or at least 200 feet.
b.Bump detection: on.
c.Dip detection: on.
d.Resolution : 0.01 inch.
e.Low pass filter: off.
f.All other filters: off. Apply the following IRI requirements where longitudinal grade is 4.5 percent or less, pavement on tangent alignment and pavement on horizontal curves having a centerline radius of curve 1,000 feet or more must meet the surface smoothness requirements for the smoothness schedule specified. The Engineer will add consecutive 0.1 mile sections of roadway tested together to obtain for Highway Construction Page 258 of 715 a mile section. Overlapping of the 0.1 mile or 1 mile sections to change cumulative test results is not allowed.
a.Schedule I projects. Target IRI of 60.0 to 70.0 inches per mile or less per 0.1 mile. Corrective action required above 95.0 inches per mile per 0.1 mile.
b.Schedule II projects. Target IRI of 70.0 to 80.0 inches per mile or less per 0.1 mile. Corrective action required above 95.0 inches per mile per 0.1 mile.
c.Schedule III projects. Target IRI of 95.0 inches per mile per 0.1 mile. A Schedule II project adjoining existing pavements may be revised to a Schedule I project provided the adjoining pavement is ground and maintaine d at the minimum specified thickness. A profile is not required in the following areas of pavement :
a.Pavement on horizontal curves having a centerline radius of curve less than 1,000 feet and pavement within the superelevation transition of such curves.
b.Pavement within 50 feet of a transverse joint that separates the pavement from an existing pavement not constructed under the contract .
c.Pavement for ramps, approaches, structure decks, city streets, or county roads.
d.Pavement within 50 feet of a transverse joint that separates the pavement from a structure deck or an approach slab. After individual high point grinding has been completed, perform additional grinding in sections requiring corrective action to reduce the IRI to a maximum of 80.0 inches per mile in any 0.10 mile along any line parallel to the centerline. Perform additional grinding as necessary to extend the area gr ound in each lateral direction so the lateral limits of grinding are at a constant offset from, and parallel to, the nearest lane line or pavement edge, and in each longitudinal direction so the grinding begins and ends at lines perpendicular to the pavement centerline, within any one ground area. Ensure ground areas are neat, rectangular areas of uniform surface appearance. Produce a pavement surface true to grade and uniform in appearance with longit udinal corrugations that present a narrow ridge, corduroy appearance. Produce ridge peaks approximately 1/16 inch higher than the bottoms of the grooves with approximately 53 to 57 evenly spaced grooves per foot. Remove fins resulting from grinding before opening to traffic. Use power driven, self -propelled grinding equipment specifically designed to smooth and texture portland cement concrete pavement with diamond blades. Use a machine wit h an effect ive wheel base of at least 12 feet and of a shape and dimension that does not encroach on traffic movement outside the work area. Use equipment capable of grinding the surface without causing spalls at cracks, joints, or other l ocations. Smoothly feather transitions between ground and unground areas of concrete at transverse boundaries. Do not exceed 1/8 inch vertical variations in elevation between ground and unground areas of concrete . Feather out these variations with additional grinding using an appropriate cross -slope adjustment . for Highway Construction Page 259 of 715 Grinding to obtain smoothness incentives will be allowed provided the grinding will not result in pavement thickness below the s pecified thickness. If correction of the roadway as specified will not produce satisfactory results as to smoothness or it reduces pavement thicknesses and serviceability, the Engineer may accept the completed pavement and will deduct from monies due or that may become due to the Contractor the sum of $1,000 for each individual high point or $7,500 for each 0.1 mile section. In these circumst ances, the Engineer’s decision whether to accept the completed pavement or to require cor rections as described is final.
L.Curing. Cure concrete pavement with a system 2 white- pigmented, membrane- forming curing compound as specified in709.01 . Cure the concrete with 2 applications of the curing compound for a total coverage of at least 1 gallon per 75 square feet. Apply each application of the curing compound under pressure at a rate at least 1 gallon per 150 square feet on textured surfaces of concrete pavement . Apply the second coat of membrane in the opposite direction of the first coat. Uniformly spray the entire surface of the pavement with the 2 complete applicati ons of the membrane- forming curing compound after finishing the surface and sides and before the initial set has taken place by an approved machine method. Thoroughly mix the membrane- forming curing compound before use. Agitate the curing compound during application to prevent settling and separation. Show the intended method for mixing and agitating the compound before each paving usage for Engineer approval. Hand spray odd widths or shapes and slab edges. Do not apply curing c ompound to the inside faces of joints to be sealed. If the film is damaged within 72 hours, immediately repair the damaged portion with additional compound at no additional cost to the Department. The Engineer will sample, test, and approve each manufacturer’s identified lot of curing compound before use. Allow 3 weeks for laboratory testing of the curing compound once it has been received by the Central Materials Laboratory . Quantities of curing compound over 1,000 gallons can be inspected and sampled by the Department at the manufacturer’s plant for acceptance testing. Direct inspection requests to the Engineer and the Central Materials Laboratory in writing at least 30 calendar days before ordering material.
M.Cold Weather Concreting Work Plan. Submi t a cold weather concreting and curing work plan for approval when there is a probability of air temperatures below 40°F during the placing and curing periods. Detail the methods and equipment proposed to produce mixed concrete and deliver it with a temperature of between 50°F and 85°F at the time of placing. The water and/or the aggregate may need to be heated to a temperature from 70°F to 150°F. Include the methods to protect the finished concrete from freezi ng and cracking and address how curing will be continuously monitored to ensure the required strength is developed before opening to traffic. Detail the methods and equipment proposed to ensure the required concrete temperatures are maintained. Include the materials and labor anticipated for the work. Do not place concrete until the plan is approved. When the ambient temperature falls below 40°F, meet the following concreting operations requirements: for Highway Construction Page 260 of 715 1. Provide a supply of suitable blank eting material alongside the work, before placing the concrete pavement , in quantities sufficient to cover the anticipated area of concrete pavement placed during the expected period of cold weather protection.
2.Anytime the air temperature is expected to drop to 32°F or less, spread the blanketing material provided over the surface and exposed sides of the concrete pavement to a dept h sufficient to prevent freezing of the concrete. Immediately cover the concrete whenever the air temperature drops to 35°F or lower.
3.Provide at least 1 approved calibrated temperature recording device for every 2,500 square yards of concrete pavement placed. Whenever the air temperature is expected to drop below 40°F, place and operate recording thermometers. Remove and replace concrete damaged by frost action at no additional cost to the Department.
4.The C ontractor may remove the protection blankets in a minimum sized area for a time not to exceed ½ hour for sawing joints .
5.Maintain a temperature at the surface of the concrete of at least 40°F for 7 calendar days. After 4 calendar days, the cold weather protection can be suspended if it is demonstrated with field- cured cylinders or maturity method that the concrete pavement has reached a compressive strength of at least 2,500 psi.
6.When protectio n blankets are no longer required, remove the blankets so the temperature of the concrete does not drop more than 40°F during the first 24 hours. Monitor the temperature with a recording thermometer atta ched to the edge of the concrete pav ement or as approved.
7.Provide thermocouples and its associated equipment to show compliance with the cold weather plan.
N.Sealing Joints . Construct joints as specified in 625, in accordance with the sealant manufacturer’s written instructions, or as otherwise specified. Install joint sealant after grinding for surface smoothness and before the pavement is opened to tr affic. Perform joint sealing only when the ambient and pavement temperatures are 50°F or higher, the pavement surface is dry, and weather conditions are dry, or in accordance with the manufacturer’s written instructions. Provide sealant material as specif ied in 704. Submit a copy of the sealant manufacturer’s written instructions for handling, storage, and application before beginning the work.
1.Neoprene Compression Seal . When neoprene compression seal is used, install the sealant material into the joint as specified in 625 , using equipment and techniques recommended by the manufacturer. Ensure the finished joint seal has the shape factor and surface recess as specified. Install the longitudinal joint seal first and then cut at the intersections of the transverse joints . Install the transverse joint seal through the cut in the longitudinal seal to form a tight intersection. Install the transverse seal in 1 continuous piece. Do not stretch t he seal in excess of the manufacturer’s written instructions. Do not twist the seal or have deformities that interfere with the seal making complete contact with the joint face.
2.Silicone Joint Sealant. Use the size backer rod as specified and the type of bond breaker recommended by the sealant manufacturer, if required. Clean the joint within 1 hour before placing the sealant by sandblasting and air blowing with compressed air at 100 psi minimum. Provide oil for Highway Construction Page 261 of 715 and moisture- free compressed air. Do not place the sealant if dust, moisture, oil, or foreign material is present on the concrete receiving the sealant. Apply the sealant material into the joint using equipment and techniques recommended by the manufacturer. Ensure the fi nished joint seal has the shape factor and surface recess as specified. Remove excess joint sealing material immediately and clean the pavement surface. Do not use sand or similar material as a cover for the seal. The Engineer will reject the joint material for failure in adhesion or cohesion. Repair the joint to the Engineer’s satisfaction at no additional cost to the Department. Have a technical representative of the manufacturer present at the project site for at least the first 2 days of joint preparation and sealing when silicone joint sealant or neoprene compression seal is used. Follow the manufacturer’s written instructions and/ or recommendations made by the technical representative as approved. A separate payment will not be made by the Department for the services of the technical representative or for implementing the approved recommendations.
O.Multiple Lane C onstruction. Do not place concrete in adjacent lane(s) sooner than 48 hours after finishing of the first lane(s). The Engineer may allow the operation of equipment and trucks on newly paved concrete, due to the lack of space elsewhere, if conditions are deemed justified and meet these conditions:
1.Determine compressive strength by maturity testing in accordance with ASTM C1074. Validate the maturity curve with the first placement and every 14 calendar days or 20,000 cubi c yards thereafter, whichever is greater. Cure cylinders used for validation testing using the same procedures as used in developing the initial maturity -strength relationship. When initially vali dating the maturity curve, validate at least 2 points on the maturity curve, at least 1 of which will be at a period of less than 7 calendar days. At least one point occurring within 7 calendar days is required for subsequent validation. A maturity curve w ill be considered valid if the validation points are within 10 percent of the original maturity curve. Develop the maturity -strength relationship and provide maturity curves along with supporting data and field procedures for monitor ing maturity for approval at least 10 calendar days before use. Provide equipment, including thermo or maturity meters, thermocouples, wire, and qualified personnel to monitor maturity and submit information.
2.Protect the surface of the new pavement from scarring and abrasion. Operat e equipment on mats, skids, or other approved protective devices. Remove accumulation of concrete, sand , gravel, or other debris deposited on the new pavement as directed. Replace cracked or broken panels or slabs on the new pavement , caused by operating the equipment, at no additional cost to the Department.
P.Protection of Pavement . Repair or replace pavement damag ed before final acceptance at no addition al cost to the Department. Protect the edges and surface of the unhardened concrete against the effects of rain. Use metal or wood protective materials having a width of at least the thickness of the pavement at its edge f or the protection of the pavement edges and covering material (e.g., burlap or cotton mats, curing paper, plastic sheeting) for the protection of the pavement surface. Have these materials available onsite while paving. When rain for Highway Construction Page 262 of 71 5 appears imminent, stop paving operations and begin placing forms against the sides of the pavement and cover the surface of the unhardened concrete with the protective covering.
Q.Opening to Traffic. Do not allow traffic on the pavement until a 3,500 psi or greater compressive strength is attained determined by maturity testing in accordance with ASTM C1074. Develop the maturity -strength relationship and submit maturity curve s along with supporting data and field procedures for monitoring maturity for approval at least 10 calendar days before use. Provide equipment, including thermo or maturity meters, thermocouples, wire, and qualified personnel to monitor maturity and submit informat ion. Validate the maturity -strength relationship with the first field placement and then every 14 calendar days or 20,000 cubic yards, whichever is greater. Cure cylinders used for validation testing using the same procedures as used in developing the initial maturity -strength relationship. When initially validating the maturity curve , validate at least of 2 points on the maturity curve, at least one of which will be at a period of less than 7 calendar days. At least 1 point occurring within 7 calendar days is required for subsequent validation. A maturity curve will be considered valid if the validation points are within 10 percent of the original maturity curve. Clean the pavement before opening to traffic.
409.04 Method of Measurement.
The Engineer will measure acceptably completed work for concrete pavement by the square yard. The square yard measurement will be based on the width of the top surface of the pavement as shown on the typical section and additional widening where specified or directed. The length will be measured horizontally along the centerline of each ramp or roadway. Pavement areas w ill be computed according to Table 109.01- 1. The Engineer will not make a final measurement of the completed pavement , except for authorized changes during construction or where many errors are found in the contract quanti ty. The Engineer will then compute a revision or correction and add to or deduct from the contract quantity.
409.05 Basis of Payment .
The Department will pay for acceptable quantities as follows: Pay Item Pay Unit Concrete Pavement ................................................................................ SY Drilling holes for the dowels is incidental and the cost included in the contract unit price. Verifying dowel bar location is incidental and the cost included in the contract unit p rice. The Department will not pay for field- cured cylinders. The Department will not pay for grinding and related expenses, including disposal of ground material, traffic control, flagging, profiling, and temporary striping. The Department will not make additional payment for corrective treatment to meet smoothness requirements.
A.Thickness Price Adjustment . The Department will make the following price adjustment to the contract unit price for each evaluation section quantity exceeding the thickness specified. If thickness measurements show deficient thi ckness, the for Highway Construction Page 263 of 71 5 Contractor has the option of removing and replacing the pavement at no additional cost to the Department or leaving the pavement in place and receiving the deductions specified in Table 409.05- 1. Table 409.05-1 – Thickness Price Adjustment Excess or D eficiency in Thickness, inch Price Adjustment , Percent of Contract Unit Price Over +0.50" 100 +0.35" to +0.50" 102 +0.25" to +0.34" 103 +0.11" to +0.24" 105 +0.10" to -0.10" 100 -0.11" to -0.24" 85 -0.25" to -0.34" 70 -0.35" to -0.50" 50 Over - 0.50" 0 The Department will not pay an incentive for thickness in evaluation sections where pavement grinding has occurred to achieve smoothness. The Engineer will evaluate areas of pavement found deficient in thickness by more than 0.5 inch and determine if the deficient area is sufficient to seriously impair the anticipated service life of the pavement. Remove the affected areas of pavement within the limits specified and replace it with concrete of the specified quality and thickness at no additional cost to the Department. Remove the sections of pavement the full length between transverse joints . If, in the Engineer’s opinion, a deficiency in excess of 0.5 inch will not seriously impair the anticipated service life of the pavement, the Contractor may elect to leave the pavement in place, but will not receive payment for the deficient area of pavement . When the pavement contains no longitudinal joints , the area of such pavement for which payment will not be made is the product of the full width of the strip placed as a unit, multiplied by the distance bet ween probes, on both sides of the deficient measurement that shows measurements within the thickness l imits. Where the pavement contains longitudinal joints, the width used by the Department is the width between longitudinal joints and the edge of the pavement. The Engineer may order the Contractor to core drill the finished pavement to determine thickness of the pavement in areas where smoothness corrections are made. The Engineer will determine the pavement thickness by coring after smoot hness corrections have been completed.
B.Profile Incentive . The Contractor is entitled to a profile incentive payment for each evaluation section as determined by the smoothness schedule specified. An evaluation section is a 12 feet wide placement, 0.1 mile long or fraction as applicable, with profiles in the driving lanes only. The 0.1 mile long sections runs consecutively from the for Highway Construction Page 264 of 715 point paving begins to the point paving is interrupted (e.g., at bridges, end of lane paving, areas specifically excluded by the specifications). The profil e index requirements are specified in 409.03.K. The Department will not pay a profile incentive payment for pavement on the roadway shoul ders, turn lanes, or other miscellaneous pavement . The Department will pay a profile incentive as follows.
1.Schedule I Projects.
a.For an IRI between 60.0 inches per mile per 0.1 mile and 40.0 inches per mile per 0.1 mil e, use the following formula: Profile incentive = (60.0 - Section IRI) x $85.00.
b.For an IRI less than 40.0 inches per mile per 0.1 mile, the profile incentive is $1,700 for each 0.1 mile section.
c.For an IRI great er than 60.0 inches per mile per 0.1 mile, a profile incentive payment will not be made.
2.Schedule II Projects.
a.For an IRI between 70.0 inches per mile per 0.1 mile and 40.0 inches per mile per 0.1 mile, use the following formula: Profile Incentive = (70.0 - Section IRI) x $45.00.
b.For an IRI less than 40.0 inches per mile per 0.1 mile, the profile incentive is $1,350 for each 0.1 mile section.
c.For an IRI greater than 70.0 inches per mile per 0.1 mile, a profile incentive payment will not be made.
3.Schedule III Projects.
a.A profile incentive payment will not be made. The Department will make only one profile incentive payment , whichever payment is greater in accordance with the initial IRI reading determined as specified in 409.05.B. When more than 1 profile run is made in an evaluation section, the Department will use the roughest IRI to calculate the profile incentive payment . The Engineer may reject the pavement when the initial IRI exceeds 120 inches in a 0.1 mile section. If grinding is required as specified in 409.03.K, make a profile run after grinding to ensure minimum specifications have been met. for Highway Construction Page 265 of 715 SECTION 410 - RESERVED
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 278–300 of 768.