502PORTLAND CEMENT CONCRETE PAVEMENT, PCCP

502.01Description

This work shall consist of portland cement concrete pavement, PCCP, placed on a prepared subgrade or subbase in accordance with 105.03.

MATERIALS

502.02Materials

Materials shall be in acco rdance with the following: 10

Admixtures .................................................................. 912.03 Concrete Coarse Aggregate, Class AP ........................ 904.03, ITM 226 Fine Aggregate, Size No. 23 ........................................ 904.02 Fly Ash ........................................................................ 901.02 Liquid Membrane Forming Compound ....................... 912.01(e) Portland Ceme nt .......................................................... 901.01(b) Rapid Setting Patch Materials ..................................... 901.07 Silica Fume .................................................................. 901.04 Slag Cement ................................................................ 901.03 20 Water ........................................................................... 913.01

502.03Concrete Mix Design

A concrete mix design submittal, CMDS, shall be in accordance with 502.04. The CMDS shall be submitted to the DTE. The CMDS shall be submitted a minimum of seven calendar days prior to production utilizing the Department provided spreadsheet and shall include the following:

The aggregate blend on the CMDS may produce an optimized aggregate gradation in accordance with the Department provided spreadsheet. If an optimized aggregate 40 gradation is used, it shall consist of, at a minimum, one concrete coarse aggregate and one fine aggregate, No. 23. One additional class A or higher intermediate-sized coarse aggregate may be included if approved by the Engineer.

502.03

The absolute volume of the mix design shall be 27.0 cu ft at the design air content of 6.5%.

Production shall not commence until the DTE has issued the concrete mix design for production, CMDP.

Any of the following changes or adjustments to a CMDP shall require a new CMDS to be submitted to the DTE, referencing the original CMDP. The new CMDS shall be submitted to the DTE utilizing the Department provided spreadsheet a minimum of one work day prior to production. Production shall not commence until the DTE has issued the CMDP.

A CMDP in accordance with either 501.05 or 502.04 from a previous contract may be submitted to the DTE for consideration for use on the current contract. The 70 DTE will notify the Contractor when the review is complete and if the previously used CMDP can be used on the current contract.

502.04Concrete Mix Criteria

Chemical admixtures Type A, Type B, T ype C, Type D, Type E, and Type F may be allowed if shown on the CMDP. The supplied concrete mix shall include one of the following water reducing admixtures: Type A, Type D, Type E, or Type F.

The CMD shall produce workable concrete mixtures, with the minimum amount 80 of water, and having the following properties.

Targets for the CMD:

Portland cement c ontent .............................................. 564 lb/cu yd A Minimum water/cementitious ratio ............................. 0.340 B Maximum water/cem entitious ratio ............................. 0.435B Maximum portland cement reduction for slag cement replacement ................................. 30% Slag cement/portland cement substitution ratio ........... 1.00 by weight 90 502.04

Maximum cement reduction fo r fly ash replacement .. 20% Fly ash/portland cements ubstitution ratio ................... 1.25 by weight Air Content .................................................................. 6.5% Minimum modulus of r upture...................................... 570 psi at 7 daysC Relative Yield .............................................................. 1.00

Field Acceptance Properties:

Minimum water/cementitious ratio ............................. 0.320 B Maximum water/cem entitious ratio ............................. 0.450B 100 Slump, formed ............................................................. 2 to 6 in. Slump, slipformed ....................................................... 1.25 to 3 in. Air Content .................................................................. 5.0% to 8.0% Minimum modulus of r upture...................................... 570 psi at 7 days C Relative Yield .............................................................. 0.98 to 1.02

A The target cement content during production shall not be adjusted from the value stated on the CMDP.

B The water cementitious ratio during production shall not 110 deviate more than 0.020 from the target stated in the CMDP and shall not fall outside the limits above.

C Beams shall be standard cured in a water tank in accordance with AASHTO T 23 and 505.01(a). The water does not need to be saturated with calcium hydroxide. Minimum flexural strength for opening to traffic shall be in accordance with 506.12.

Class C concrete in accordance with 702 using Class AP coarse aggregate may be 120 substituted in PCCP.

Blended portland pozzolan cements, fly ash, or slag cement may only be incorporated in the concrete mix when the ambient temperature is above 50°F during the entire placement period. If Type IP, Type IP-A, Type IS, or Type IS-A cements are to be used, the minimum portland cement content shall be increased to 598 lb/cu yd. The use of fly ash or slag cement will not be allowed when blended cement types IP, IP-A, IS, or IS-A are used.

Patching concrete in accordance with 506.04(b) shall be used.

502.05Job Control

Control of PCCP for air content, slump, or relative yield will be determined from tests performed by the Engineer in accordance with 505. Concrete and necessary labor for sampling shall be furnished as required by the Engineer. Testing will be in accordance with the Frequency Manual.

502.05

The Engineer will notify the Contractor when test results for air content, slump, or relative yield are outside the requirements of 502.04. Rounding will be in 140 accordance with 109.01(a). The Contractor shall adjust the mixture su ch that it is in accordance with 502.04.

CONSTRUCTION REQUIREMENTS

502.06General

Equipment for PCCP shall be in accordance with 508.

Aggregate stockpiles shall be located in well drained areas to prevent the soil from pumping into and contaminating the aggregate that is to be used in PCCP. Stockpiles 150 shall be built in layers not to exceed 6 ft. Upper layers shall be prevented from spilling onto the lower layers.

Aggregate stockpiles shall be worked to minimize segregation and maintain uniform moisture content. Aggregates which have become contaminated shall not be used.

The water measuring device will be checked under actual working conditions or at any other time deemed necessary. All labor and equipment required for calibrating and checking shall be furnished. 160

The volume of the batched concrete sh all not exceed the manufacturer’s standard rating for the concrete mixer.

502.07Preparation of Subgrade

The subgrade shall be shaped to the required grade and section, free from all ruts, corrugations, or other irregularities, and uniformly compacted in accordance with 207. Surfaces on which a mixture is placed shall be free from objectionable or foreign materials at the time of placement.

502.08Preparation of Subbase

Subbase, if required, shall be placed and shaped to the required grade and section in accordance with 302. Construction traffi c shall not be allowed on the aggregate drainage layer of the subbase, except where PCCP placement is restricted. Exceptions shall be submitted for approval.

502.09Placement

Placement of PCCP shall be by the slipfo rmed or formed methods with equipment specified in 508.04. The subgrade or subbase shall be uniformly moist at the time of PCCP placement. Excessively dry subgrade or subbase shall be sprinkled with water. 180

If the slip-form method is used the subgrade or subbase shall firmly support the paving equipment to construct the specified alignment and grade. The slip-form paver shall be operated with as nearly a continuous forward movement as possible. If it is 502.06

necessary to stop the forward movement of the paver, the vibratory and tamping elements shall also be stopped. Edge slump of PCCP shall not exceed 1/4 in.

When the slip-form method is used, the Contractor shall have metal or wood forms available for protection of the PCCP edges should excessive edge slump occur.

If forms are used, they shall be firmly supported by the subbase or subgrade for the entire length of the form at the specified alignment and grade. The alignment of the forms shall not deviate more than 1/4 in. in the horizontal direction from the planned PCCP width for tangent sections.

Forms shall be staked in to place with a minimum of three pins for each 10 ft section. A pin shall be placed at each side of every joint. Form sections shall be locked tightly and be free from play or movement in any direction. No excessive settlement or springing of forms under the finishing machine will be allowed. Forms shall be cleaned and oiled prior to the placing of concrete. 200

Forms shall be kept a minimum of 50 0 ft ahead of concrete placement when distance allows. Any material displaced during form setting operations shall be thoroughly compacted. If material under the forms becomes unstable before concrete is placed, the forms shall be removed, the grade corrected, and the forms reset.

502.10Concrete Mixing and Transportation

Concrete mixing and transportation shall be completed by central mixed, shrink mixed, or transit mixed methods. The minimu m batch of concrete shall be 2 cu yds. When the concrete temperature is 90°F or above, discharge from non-agitating 210 equipment shall be completed within 30 minutes of mixing the water, cement, and aggregates. For concrete temperature below 90°F, discharge from non-agitating equipment shall be completed within 45 minutes of mixing the water, cement, and aggregates. The concrete temperature w ill be measured in accordance with ASTM C1064 at the point of delivery. Discharge from a truck agitator or a truck mixer shall be completed within 90 minutes of mixing the water, cement, and aggregates.

Concrete shall be uniformly mixed when delivered to the job site. Batch tickets for each load of PCC shall indicate the we ight of cement, SCM, aggregates, volume or weight of water, and the type and volume of admixtures. The weight of the cement 220 shall be within 1% of the CMDP, the saturated surface dry weight of the aggregates shall be within 2% of the CMDP, and the volume or weight of water shall be within 1% of the required amount.

The Engineer may conduct additional testi ng to verify uniformity of the mixture. Additional testing will consist of slump tests taken in accordance with AASHTO T 119 at approximately the 1/4 and 3/4 points of a load. If the slumps differ by more than 1 in. when the average slump is 3 in. or less, or by more than 2 in. when the average slump is greater than 3 in., paving operations may be suspended while the mixing process is jointly reviewed and problems resolved by the Engineer and the 230 Contractor. 502.10

Wash water shall not be used as a portion of the mixing water.

When concrete is delivered in transit mixers, additional water to increase the workability of a load may be added within 45 minutes of initial mixing. Any addition of water shall be noted on the batch ticket and shall not occur as a continuing operation.

Stationary mixers shall be operated at the manufacturer’s recommended drum speed. Batches shall not exceed the nominal capacity of the mixer. 240

Central mixed concrete shall be completely mixed in a stationary mixer and transported in a truck agitator, truck mixer at agitating speed, or non-agitating equipment.

Mixing for central mixed concrete shall be no less than 60 s per batch. The mixing time shall be measured from the time all cem ent and aggregates are in the drum. The batch shall be so discharged into the mixer that some of the water enters in advance of the cement and aggregates. All required water shall be in the drum by the end of the 250 first quarter of the specified mixing time.

If a truck mixer or truck agitator is used for transportation, the concrete shall be agitated at the agitation speed designated by the manufacturer.

Shrink mixed concrete shall be partially mixed in a stationary mixer and the mixing completed at the plant in a truck mixer.

The time in a stationary mixer for shrink mixed concrete may be reduced to 260 approximately 30 s. Mixing shall then be completed in a truck mixer at the plant by 50 to 100 revolutions of the drum at the mixing speed designated by the manufacturer. Agitation during transportation shall be at the agitation speed designated by the manufacturer.

Transit mixed concrete shall be completely mixed and transported in a truck mixer.

Mixing for a truck mixer loaded to rated capacity shall be 70 to 100 revolutions 270 of the drum at the mixing speed, but not less than the number of revolutions recommended by the manufacturer. Discharge shall be completed prior to 300 revolutions of the drum.

502.11Weather Limitations

PCCP shall not be placed on a frozens ubgrade or subbase. PCCP operations shall not begin until the ambient temperature is 35°F and rising. PCCP operations shall be 502.11

discontinued when the ambient temperature is descending and is 40°F or below. PCCP operations may occur outside these temperatures when authorized in writing. Regardless of placement temperature, suffic ient means shall be taken to prevent the 280 PCCP from freezing prior to attaining opening to traffic strengths in accordance with

502.18. Any PCCP damaged by freezing shall be removed and replaced

When concreting is authorized during cold weather, the aggregates may be heated by either steam or dry heat prior to being placed in the mixer. The apparatus used shall heat the mass uniformly and prevent the occurrence of overheated areas which might damage the materials. Unless authorized, th e temperature of the mixed concrete shall not be less than 50°F and not more than 80°F at the time of placement.

When the water or the aggregates are heated, they shall be a minimum of 70°F or 290 a maximum of 150°F. When either aggregates or water are heated to above 100°F, they shall be combined in the mixer before the cement is added.

502.12Placing Concrete

The batches shall be deposited uniformly requiring minimal rehandling. The plastic concrete shall not be segregated during placement. Rakes shall not be used to handle plastic concrete. Dowel bars and assemblies shall not be displaced during placement of concrete. Plastic concrete shall not be contaminated with earth or other foreign matter.

Concrete shall be thoroughly consolidated against the faces of all forms or adjacent concrete surfaces. Hand placed conc rete shall be thoroughly consolidated with the use of a vibrator. Vibrators shall not be operated in any one location to avoid bringing excessive mortar to the surface. Vibrators shall not come in contact with dowel bar assemblies, subgrade, subbase, or forms.

Concrete shall be placed around manholes or similar structures in accordance with 720.

The Contractor shall be responsible for the protection of the existing joints from 310 the intrusion of fresh concrete mortar and for all damage to existing pavement caused by the operation of mechanical equipment. Concrete materials that fall on or are worked into the joints or surface tines of an existing slab shall be removed immediately.

Concrete shall not be mixed, placed, or finished when the natural light is insufficient, unless an artificial lighting system in accordance with 702.26 is operated.

The Contractor shall have sufficient ma terials, available at all times, for the protection of unhardened PCCP from the effects of rain. Covering material such as 320 burlap or polyethylene sheeting shall be provided. When rain appears imminent, paving operations shall stop. All available personnel shall be used to cover the PCCP.

502.12

502.13Joints

Joints shall be in accordance with 503.

502.14Finishing

PCCP shall be finished in accordance with 504.

502.15Curing 330

PCCP shall be cured with a white pigmented liquid membrane forming compound selected from the QPL of Liquid Membrane Forming Curing Compounds. Alternative methods of curing shall be as approved by the Engineer. Curing shall be in accordance with 504. For formed PCCP, immediately after the forms are removed, the sides of the PCCP shall be cured.

502.16Form Removal

Forms may be removed as soon as the PCCP has hardened sufficiently to prevent edge spalling or other damage. Form pullers shall not be supported on the PCCP during form removal operations. 340

502.17Pavement Inspection

The Contractor and the Engineer will conduct an inspection of the new PCCP for any damage, including freezing or random cracks. The inspection and all necessary repairs shall be completed prior to opening the pavement to non-construction traffic. All random, full-depth cracks in the PCCP shall be corrected in accordance with

503.06. All other damages shall be repaired by approved methods

Opening to Traffic

PCCP may be opened to equipment and traffic when the flexural strength of the 350 test beams indicates a modulus of rupture of 550 psi or greater. ITM 402 may be used as an alternate method to determine the flexural strength. If adequate strengths are not achieved, an investigation by the Engineer and the Contractor will be conducted to determine if the PCCP is deficient. Resolutions for all deficiencies will be developed at the completion of the investigation. Prior to opening to traffic, cracks and joints shall be sealed in accordance with 503.05 and the PCCP shall be cleaned.

502.19Pavement Corrugations

Pavement corrugations shall be in accordance with 606.

502.20Pavement Smoothness

Pavement smoothness will be in accordance with 501.25 except inertial profiler requirements will not apply.

502.21Pavement Thickness

PCCP thickness shall be determined after all corrective grinding. The Contractor shall obtain cores at the locations determ ined by the Engineer in accordance with ITM 802. Cores, 4 in. in diameter, shall be taken in the presence of the Engineer for the full depth of the PCCP. The Engineer will take immediate possession of the cores. 502.13

Cores shall not be taken within 2 ft of the edge of PCCP, over dowels, or within 5 ft 370 of a transverse construction joint. Cores shall be taken and measured in accordance with ITM 404. All core holes shall be fille d with PCC or rapid setting patch material within 24 h of drilling.

If a core measurement reveals that the pavement is more than 1/2 in. deficient in thickness, additional cores shall be drilled at 20 ft intervals on each side of the original core. These additional cores shall be on a line which passes through the original core and parallel to the centerline of the pavement. The drilling shall continue in both directions at 20 ft intervals until two successive cores indicate a thickness deficiency of 1/2 in. or less, or where cores can no longer be drilled in the new PCCP. 380

If a core indicates a thickness deficiency of more than 1 in. and two cores drilled adjacent at 20 ft intervals i ndicate a thickness deficiency of not more than 1 in., additional cores shall be drilled at 5 ft intervals on each side of the initial core. The drilling shall continue in both directions at 20 ft intervals until two successive cores indicate a thickness deficiency of 1/2 in. or less, or where cores can no longer be drilled in the new PCCP.

When a single core indicates a thickness de ficiency of more than 1 in., or if two or more adjacent cores indicate a thickness deficiency of more than 1/2 in., the 390 investigation will be expanded to include adjoining PCCP. The additional cores shall be taken from the adjoining traffic lanes or shoulders at the same station at which the first core or cores indicated the deficiency, whether the lane was paved at the same time or not.

The width of adjudicated PCCP shall be the width of pavement lane in which the deficiency occurs. Pavement that has been replaced shall be investigated for thickness.

The quantity of PCCP for each pay item will be defined as a section. The section 400 will be divided into subsections of 1,200 sq yds. Sections less than 1,200 sq yds shall not be cored. A minimum of one core shall be drilled at a random location within each subsection. A section greater than or equal to 1,200 sq yds shall have a minimum of four cores drilled. Partial subsections shall not be cored unless otherwise directed. Widening of 3 ft or less shall not be cored unless otherwise directed.

Formed drives shall not be cored unless otherwise directed. Verification of the required pavement depth on formed drives shall be checked in the presence of the Engineer prior to pouring, by making stringline measurements every 10 ft across the width of the drive. Any location deficient in thickness by 1/4 in. or more shall be 410 corrected prior to placing PCCP.

The thickness of the PCCP for each section shall be the average lengths of all cores from the section. However, no cores shall be included from areas for which no 502.21

payment will be made. Where PCCP has been removed and replaced, the initial core lengths will be discarded and the core lengths of the replaced PCCP will be substituted. Any core measurements exceeding the specified PCCP thickness by more than 1/2 in. will be recorded as the specified PCCP thickness plus 1/2 in. Calculations shall be to the nearest 0.1 in. 420

If the average PCCP thickness is equal to or greater than the specified thickness, no adjustments will be made. If an average PCCP thickness is less than the specified thickness by up to 1/2 in., payment for that section will be adjusted in accordance with the following:

Q T = Q x U x (1 – M2/S2) where:

QT = quality assurance assessment for thickness Q = placed quantity of the PCCP section M = average PCCP thickness of the section S = specified PCCP thickness of the section U = unit bid price.

Where two adjacent cores indicate a thickne ss deficiency of more than 1/2 in., no payment will be made unless the PCCP is removed and replaced. Payment for PCCP with non-adjacent cores indicating a thickness deficiency of more than 1/2 in. will be in accordance with 502.21(c).

The limits of non-payment shall extend from deficient core to the transverse joint location nearest the first additional core indicating a thickness deficiency of less than 1/2 in. 440

Where two adjacent cores indicate a thickne ss deficiency of more than 1 in. the PCCP shall be removed and replaced. No n-adjacent cores indicating a thickness deficiency of more than 1 in. do not require removal and replacement.

The limits of removal and replacement sha ll extend from the deficient core to the transverse joint location nearest the first additional core indicating a thickness deficiency of less than 1/2 in.

502.22Method of Measurement

PCCP will be measured by the square yard of the thickness specified. The area of PCCP will be the planned width of the pavement multiplied by the length of the pavement, or as directed in writing. The width of the pavement will be as shown on the typical cross-section of the plans. The length of the pavement will be measured parallel to the surface of the pavement along the centerline of the roadway or ramp, excluding paving exceptions as shown on the plans. 502.22

Milled pavement corrugations will be measured in accordance with 606.04.

502.23Basis of Payment

The accepted quantities of PCCP will be paid for at the contract unit price per square yard for the thickness specified, complete in place.

Adjustments to the contract payment with respect to thickness will be included in a quality assurance adjustment pay item in accordance with 109.05.1.

Milled pavement corrugations will be paid for in accordance with 606.05.

Payment will be made for portland cement content of more than 564 lb/cu yd 470 when ordered in writing. Additional payment for the quantity used will be at the net unit price of portland cement as shown by certified vouchers for the quantity used in accordance with 109.05.

Payment for pavement thickness determinations will be made at the contract lump sum price for coring, PCCP in accordance with 501.31. A change order in accordance with 109.05 will be developed to adjust the cost of PCCP when the final PCCP quantity differs from the bid quantity by more than 2,400 sq yds. This adjustment covers the cost of cores for the adjusted quantity of PCCP. The adjustment, plus or minus, will be based on the difference in the number of subsections, rounded to the nearest full 480 subsection, times $100.

Payment will be made under:

Pay Item Pay Unit Symbol

PCCP, _________ _ in. .............................................................. SYS thickness

No additional payment will be made for PCCP which has an average thickness 490 above that shown on the plans.

The cost of trial batch demonstrations shall be included in the cost of PCCP.

The cost of corrections for pavement sm oothness and retexturing shall be included in the cost of PCCP.

Removal and replacement of PCCP found to be deficient or damaged by freezing shall be completed with no additional payment.

The cost of coring and refilling of the pavement holes for appeals shall be included in the cost of PCCP.

502.23