501PERFORMANCE-BASED STRUCTURAL CONCRETE

5-1 Division 500

STRUCTURES SECTION 501 – PERFORMANCE -BASED STRUCTURAL CONCRETE 501.01 DESCRIPTION . This work shall consist of designing, furnishing, and placing performance -based Portland cement concrete for structures and incidental construction. The Portland cement concrete may consist of a homogeneous mixture of cement, fine aggregate, coarse aggregate, water, admixtures, and pozzolans, proportioned and mixed according to these specifications. 501.02 MATERIALS . Materials shall meet the requirements of the following subsections: Portland Cement ................................ ................................ ................................ ......... 701.02 Portland -Pozzolan Cement ................................ ................................ ......................... 701.04 Portland -Limestone Cement ................................ ................................ ...................... 701.05 Portland Blast -Furnace Slag Cement ................................ ................................ ......... 701.06 Ternary Blended Cement ................................ ................................ ........................... 701.07 Fine Aggregate for Concrete ................................ ................................ ...................... 704.01 Coarse Aggregate for Concrete ................................ ................................ .................. 704.02 Lightweight Coarse Aggregate for Concrete ................................ ............................. 704.14 Lightweight Fine Aggregate for Concrete ................................ ................................ .704.19 Preformed Joint Filler, Cork, and Asphalt -Treated Felt ................................ ............ 707.0 6 Polyvinyl Chloride (PVC) Waters top ................................ ................................ ........ 707.08 Concrete Bonding Systems ................................ ................................ ........................ 707.1 4 Steel for Corrugated Metal Forms ................................ ................................ ............. 715.0 3 Epoxy Bonding Systems ................................ ................................ ............................ 719.01 Concrete Curing Materials ................................ ................................ ......................... 725.01 Air-Entraining Admixtures ................................ ................................ ........................ 725.02(b) Retarding Admixtures ................................ ................................ ................................ 725.02(c) Latex Admixtures ................................ ................................ ................................ .......725.02(d) Water -Reducing Admixtures ................................ ................................ ..................... 725.02(e) Water -Reducing and Retarding Admixtures ................................ .............................. 725.02(f) Water -Reducing, High Range Admixtures ................................ ................................ 725.02(g) Water -Reducing, High Range, and Retarding Admixtures ................................ .......725.02(h) Accelerating Admixtures ................................ ................................ ........................... 725.02(i)

5-2 Water -Reducing and A ccelerating Admixtures ................................ ......................... 725.02(j)

Specific Performance Admixtures ................................ ................................ ............. 725.02(k) Anti-Washout Admixtures ................................ ................................ ......................... 725.02(l) Pozzolans ................................ ................................ ................................ ................... 725.03(a) Silica Fume ................................ ................................ ................................ ................ 725.03(b) Ground Granulated Blast -Furnace Slag (GGBFS) ................................ .................... 725.03(c) Polystyrene Insulation Board ................................ ................................ ..................... 735.01 Blanket Insulation Material ................................ ................................ ........................ 735.02 Pipe Insulation ................................ ................................ ................................ ........... 740.06 Water ................................ ................................ ................................ .......................... 745.01 Concrete Repair Material s ................................ ................................ ......................... 780.01 Normal weight coarse aggregate for superstructures shall be conditioned so that the total moisture percentage shall be the absorption percentage plus, at a mini mum, 0.25% free moisture for the aggregate. 501.03 CLASSIFICATION AND PROPORTIONING . Concrete shall meet the requirements specified in Table 501.03A and shall be used as shown on the Plans. TABLE 501.03A – PERFORMANCE -BASED CONCRETE CLASSES AND PROPERTIES Concrete Class 1 Min. 56 -Day Comp . Strength (psi) 2 Max. W/CM Ratio 3 Max. VSI 4 Slump/ Spread Limit Freeze/Thaw Durability 5 Air Content Limits 6 Max. Free Shrinkage Max. 56 - Day Surface Resistivity 7 Min. Durability Factor Max. Air Void Spacing Factor (in.) PCD 4,000 TBD -- N/A 8 80 0.008 TBD 0.032% Low PCS 3,500 TBD -- N/A 8 80 0.008 TBD 0.042% Low SCC 4,000 TBD 1 TBD 9 80 0.008 TBD TBD 10 Low 1 PCD = Performance Concrete, Deck PCS = Performance Concrete, Substructure SCC = Self -Consolidating Concrete 2 The concrete may be accepted if the design compressive strength from standard cured cylinders has been obtained at 28 days. Any 56 day acceptance cylinders shall be tested regardless of the results of earlier tests. 3 The maximum W/CM ratio shall be deter mined by the Contractor as established by mix qualification testing. During production, the W/CM ratio shall be less than or equal to the W/CM ratio from the approved qualification mix. See Subsection 501.03(b) . The W/CM ratio shall be rounded to two decim al places in accordance with ASTM E29 . 4 Visual stability index (VSI) as determined in accordance with ASTM C1611 . 5 The freeze/thaw durability of the proposed mix design may be established by providing mix qualification testing demonstrating conformance with either of the two requirements. Testing shall meet the requirements of either AASHTO T 161, Procedure A , or ASTM C457 , as applicable. See Subsection 501.03(b)(2) .

5-3 6 The minimum air content shall be determined by the Contractor as established by mix qualification testing. During

production, the air content shall be greater than or equal to the air content from the ap proved qualification mix. See Subsection 501.03(b)(2) . 7 The Contractor shall determine the surface resistivity in accordance with Subsection 501.03( b)(4). 8 The mix shall not exhibit segregation. If the mix does exhibit segregation, the load shall be rejected . If the spread is equal to or exceeds 20 inches, the mix shall be classified as Class SCC concrete. 9 The Contractor shall determine the spread limits in accordance with Subsection 501.03(b)( 5). The spread shall be maintained within the determine d spread limits for the placement. The mix shall not exhibit segregation. If the mix does exhibit segregation or exceeds the upper spread limit, the load shall be rejected . and subsequent loads shall be tested by the Contractor until the mix meets the allo wable limits. The Engineer may perform a J -ring test at the time of placement if blocking is a concern. 10 The Contractor shall determine the free shrinkage in accordance with Subsection 501.03( b)(1) . Class SCC concrete will be allowed for use in superstru cture elements if the free shrinkage meets the requirements for Class PCD. Class SCC concrete will be allowed for use in substructure elements if the free shrinkage meets the requirements for Class PCS. If a nominal maximum aggregate size is not specified, the Contractor shall determine the nominal maximum aggregate size using guidance from ACI 211.1 . In no case shall the maximum aggregate size exceed 1/5 of the narrowest dimension between sides of the forms, 1/3 the depth of slabs, or 3/4 of the minimum clear spacing between individual reinforcing bars, bundles of bars, or pre -tensioning strands unless approved by the Engineer. The Contractor may use industry methods to develop gradations not specified in Section 704 that are better optimized to satisfy the required concrete performance characteristics. If the Contractor is using a combined gradation, they shall provide the method or methods of how they will monitor gradation, the limits of the gradation ranges, and the frequency of monitoring. Lightweight fine aggregate may be used to replace up to 30% of the volume of normal weight sand. The gradation of the lightweight fine aggregate shall conform to the requirements of AASHTO M 195 . The lightweight fi ne aggregate shall be conditioned for enough time to fully saturate the material. The stockpile shall be constructed so that the moisture content is uniform throughout the pile. The stockpile will be allowed to drain 12 hours to 15 hours immediately prior to use, unless an alternate procedure is approved by the Structural Concrete Engineer. The Contractor shall state the method, duration and procedure used to confirm that the material is at or above its saturated surface dry (SSD) value, by weight, througho ut the pile. The use of chlorides or admixtures containing chlorides is prohibited. All admixtures will be considered incidental to the work and included in the Contract unit price of the concrete.

5-4 The concrete materials may be proportioned using the absolute volumes method in accordance with the

specified requirements. The volumetric proportioning method , such as that outlined in ACI 211.1 or other approved volumetric proportioning meth ods, shall be employed in the mix design. Prior to placing concrete on the project (or prior to the trial pour or the pre -placement meeting, whichever occurs first), the Contractor shall submit for approval the single mix design formula that satisfies all mix design qualification requirements and testing for the class of concrete specified. The mix designs shall be submitted to the Structural Concrete Engineer at the Agency’s Materials Testing and Certification Section Central Laboratory. The Structural Co ncrete Engineer may require a minimum of 8 weeks for testing, review, and approval of new mix designs. No class of concrete shall be placed on a project, including the trial pour, until the mix design is approved. If the proposed performance concrete mix design fails to meet the qualification requirements, the Contractor shall submit a revised mix design formula in writing to address the mix qualification deficiencies of the original failed mix design. Review of the revised mix design formula by the Stru ctural Concrete Engineer will be completed within 14 calendar days. Upon approval of the revised mix design formula by the Structural Concrete Engineer, testing of the revised mix design may commence. Testing of the revised mix design formula shall be comp leted within 6 months of the revised mix design formula approval. Until the testing of the revised mix design formula is completed and approved, the Structural Concrete Engineer will specify the use of an alternative, prescriptive mix design formula for th e application in question, including appropriate acceptance requirements for the prescriptive alternative mix.

5-5 (9) Determined spread lower limit and upper limit for SCC.

5-6 Testing shall be performed by a laboratory a ccredited in the specific test method. Concrete

produced by the testing laboratory to make the specimens shall have an air content equal to the Contractors proposed minimum air content with a tolerance of + 1%. The air content value from laboratory produce d concrete used for this testing will not be considered in determination of the minimum air content value allowed during production.

5-7 (c) Alkali -Silica Reactivity . The alkali -silica reactivity (ASR) of each type of aggregate shall be

measured separately based on the requirements of AASHTO T 303 or ASTM C1260 . If one or more of the aggregates exceeds 0.10% expansion, then the aggregate shall be tested again according to the requirements of ASTM C1567 or CRD -C 662 . The Contractor may elect to go directly to ASTM C1567 , or CRD -C 662 if using lithium nitrate, if they suspect that the aggregate may exceed the 0.10% expansion if tested by AASHTO T 303 or ASTM C1260 . If a lithium nitrate admixture will be used, no matter the cementitious materials combination, each aggregate will be tested by CRD -C 662 . CRD -C 662, Section 9 shall be replaced using ASTM C1567, Section 9 . The aggregates shall not exc eed 0.10% expansion when tested by any of the four allowable test methods. Testing shall be performed by a laboratory accredited in the ASTM C1260 , ASTM C1567 , or AASHTO T303 test method. Test results shall be submitted with the mix design.

5-8 Table 501.03b – Allowable Mix Design Changes for All Mix Types

Previously Approved Component or Property Being Changed Mix Design Resubmittal Requirements 1 No. of Changes Allowed Cement source If the alkali content (Na and K) of the new source is greater than that of the original source, and the original result from Subsection 501.03(c) was greater than 0.08% expansion, then updated ASR testing is required. Otherwise, no qualification testing is required. Unlimited Cement proportioning (± 5% by volume) No qualification testing required One Aggregate proportioning (± 10% by volume) No qualification testing required One Aggregate source ASR testing and gradation check by original Contractor method One Slag source If same grade is used, no qualification testing required Unlimited Silica fume source No qualification testing required Unlimited Fly ash source If either the calcium (CaO ) or the alkali (Na and K) content of the new source is greater than that of the original source, and the original result from Subsection 501.03(c) was greater than 0.08% expansion, then updated ASR testing is required. Otherwise, no qualification testing is required. Unlimited Air-entraining admixture source (Subsection 725.02(b) ) Resubmittal of freeze/thaw durability qualification testing Unlimited Shrinkage reducing admixture source ( Subsection 725.02(k) ) Resubmittal of shrinkage qualification testing Unlimited Corrosion inhibiting admixture source ( Subsection 725.02(k) ) Resubmittal of shrinkage qualification testing. If shrinkage qualification testing of the original mix design is greater than 70% of shrinkage limit, then updated shrinkage testing is required. Unlimited Latex admixture source (Subsection 725.02(d) ) Resu bmittal of surface resistivity testing Unlimited Accelerating admixture dosage increase ( Subsection 725.02(i) , Subsection 725.02(j) ) Resubmittal of shrinkage qualification testing Unlimited Accelerating admixture source (Subsection 725.02(i) , Subsection 725.02(j) ) No qualification testing required Unlimited ASR mitigating admixture source and dosage decrease (Subsection 725.02(k) ) Resubmittal of ASR qualification testing Unlimited All other admixture source and dosage changes ( Subsection 725.02 ) No qualification testing required Unlimited 1 All changes will require administrative submittal to establish proposed changes. Where required, resubmittal testing shall be completed using the same material sources and proportions from the original approved m ix design.

5-9 No new materials shall be incorporated without prior written approval of the Engineer. In no case shall

concrete from more than one mix design be permitted to be used during the same pour without prior written approval of the Engineer. The appr oved mix design will be allowed consecutive re -approval if no material proportioning or material sources have changed from the previous year’s approved mix design and the mix design is submitted with updated aggregate properties and volumes adjusted accord ingly. The aggregate properties shall be tested annually. Aggregate property values will be valid for 14 months from the date tested. The properties to be tested include, but are not limited to, specific gravity and absorption. The mix design shall be ac companied by the previously completed and accepted mix qualification test data and any applicable updated test information. The submittal shall also include all applicable quality control test results and all requests for variance from the material require ments of these specifications. 501.04 BATCHING .

5-10 The Contractor shall give the Engineer 24 -hours’ notice of intent to place concrete. Failure to give

notice which causes postponement of placing operations shall not be reason for determining an extension of Contract time per the requirements of Subsection 108.11 .

5-11 The testing laboratory shall have a minimum gross internal area of 150 square feet with a layout

providing a minimum internal width of 7 feet, in which to house and use the equipment specified. Should the Contractor elect to provide additional equipment relevant to testing of Portland cement concrete and materials, the gross inside floor area of the l aboratory shall be increased in proportion to the area required to house and operate the additional equipment. If the additional equipment is to be operated on a bench, the length of bench sections shall also be proportionally increased. Adequate ventilati on, lighting, heating, and any necessary electrical or gas connections shall be provided. Proper sanitary toilet facilities with a lavatory shall be available for use by Agency personnel at the plant site. Dedicated private telephone and internet services shall be provided to the laboratory in accordance with Subsection 631.02(a)(4) , except that selection of the service by the Engineer is not required . The laboratory shall be equipped with the following items and equipment: 1 Standard office desk, with lockable drawers or a separate lockable two -drawer file cabinet and chair 1 Agency Qualified Laboratory Binder with producer equipment calibration data 1 Set of bench sections at least 2 feet wide providing a minimum of 28 square feet of working area with under -counter shelving 1 Standard laboratory stool 1 Electronic calculator with eight digit capacity 1 Standard laboratory sink and faucet provided with an adequate supply of water meeting the requirements of Subsection 745.01 . The sink shall drain to the outside of the laboratory . 1 Bench brush 1 Floor brush 1 Motorized 8 -inch sieve shaker with an adjustable timer. The shaker’s operation shall be conducted by means of lateral and vertical motion of the sieve accompanied by jarring action with the following 8 -inch diameter sieves: 3/8 inch (9.50 mm), No. 4 (4.75 mm), No. 8 (2.36 mm), No. 16 (1.18 mm), No. 30 (0.600 mm), No. 50 (0.300 mm), No. 100 (0.150 mm), plus pan and cover.

5-12 1 Mechanical aggregate shaker with an adjustable timer, a 1 cubic foot capacity, together with

the following screens: 1 -3/4 inch (43.0 mm), 1 -1/2 inch (37.5 mm), 1 inch (25. 0 mm), 3/4 inch (19.0 mm), 1/2 inch (12.5 mm), 3/8 inch (9.50 mm), 1/4 inch (6.30 mm), No. 4 (4.75 mm), No. 8 (2.36 mm), No. 16 (1.18 mm), and pan. The aggregate shaker may be placed in a separate enclosed area or be shielded for dust and sound control. When the aggregate shaker is placed in a separate enclosed area, there shall be a minimum of 5 feet of clear space measured from the front frame of t he aggregate shaker outward, as well as a bench section measuring approximately 36 inches high, 24 inches deep, and 50 inches long located adjacent to the aggregate shaker. The area shall be well lit and ventilated. 1 Square pointed shovel 5 Five gallon pl astic buckets, with handles 1 Electronic balance with a minimum capacity of 50 pounds and accurate to 0.0002 pounds. If separate fine and coarse aggregate scales are to be used, the fine aggregate scale shall meet the requirements of AASHTO M 231, Table 2 , Class G2 with a minimum capacity of 1.75 pounds and readable to 0.0002 pounds. The coarse aggregate scale shall meet the requirements of AASHTO M 231, Table 2 , Class G5 with a minimum capacity of 50 pounds and readable to 0.002 pounds. 1 Set of standard m asses (weights) to use for verifying the accuracy of the electronic balance 2 Double -burner hot plates with variable temperature controls 3 Metal pans with a nominal size of 9 inches × 9 inches × 2 inches 5 Metal pans with a nominal size of 9 inches × 13 inches × 2 inches 1 Sample splitter with a 2 -1/2-inch chute 1 10-inch blunted trowel 1 4 foot × 4 foot minimum heavy canvas for quartering samples 1 Brass wire -bristle brush 1 Pair of heat -resistant gloves (5 00°F, short -contact) 2 1-1/2 inch soft bristle paint brushes

5-13 Acceptable substitutes for these items and equipment may be made with the app roval of the

Structural Concrete Engineer. Batching operations shall not begin until the testing laboratory has been approved as being in compliance with these specifications and all equipment and equipment calibration requirements of the Agency ’s Quality Assurance Pr ogram and Qualified Laboratory Program documents. Removal of any equipment, except upon written request and with the written approval of the Structural Concrete Engineer, will revoke any prior approvals or qualifications and require the termination of batching operations. The building or room designated as a testing laboratory shall be maintained in a clean condition by the producer and kept free of all articles not necessary for the testing of materials. Cleaning supplies sh all be furnished by the Contractor.

5-14 When beam -type scales are used, provision shall be made for indicating to the operator that the

required load in the weighing hopper is being approached. Poises shall be designed to be locked in any position to prevent unauthorized change of position. All measuring and weighing indicating devices shall be in full view of the operator while charging t he hopper and the operator shall have convenient access to all controls. The scales shall be serviced and their accuracy verified annually by a hopper -scale service person licensed by the Weights and Measures Section. For Vermont plants, an inspector repr esenting the Weights and Measures Section shall witness all testing conducted by the service person and will attach a seal to each hopper scale, provided it meets the current specifications, tolerances, and regulations adopted by the Weights and Measures S ection. Standard test weights used to determine the accuracy of hopper scales shall be certified yearly by the Weights and Measures Section in accordance with their established standards. The ready -mixed concrete producer shall hire a licensed hopper scal e service person for annual checking and service of scales. In addition, Vermont producers shall schedule an inspection with the Weights and Measures Section between February 16th and April 30th of each year, inclusive. After April 30th, Vermont plants wit hout current seals affixed to the hopper scales will not be permitted to supply concrete to Agency projects, unless otherwise directed by the Engineer or until the seals are affixed. Out-of-state concrete producers shall observe all annual hopper scale we ighing and seal requirements of their respective states.

5-15 Table 501.04a – Concrete Production T Olerances for Batching

Material Tolerance Cement ± 1% Water ± 1% Aggregates ± 2% Chemical admixtures ± 3% Mineral admixtures + 10%, - 1%

5-16 (3) Aggregates . Aggregate stockpiles shall be formed on hard, well -drained areas that prevent

contamination f rom underlying material and accumulation of excessive moisture. Aggregates from different sources or of different gradations shall not be stockpiled together. Only rubber -tired equipment shall be permitted to operate on aggregate stockpiles. Stockpiles shall be constructed as follows:

5-17 Stockpiles being watered per the specifications or allowed through producer QC

procedures shall be watered for a sufficient time to ensure consistent moisture throughout the stockpile. Aggregate stockpiles being watered shall be loaded in the bin within 1 hour of being batched. The Contractor shall conduct moisture content tests within 1.5 hours of the anticipated concrete batching time. If there is a visual difference in aggregate moisture appearance, aggregate moisture content will be tested again and new moisture test results shall be obtained and used as soon as possible. Material that has been stored in a storage bin for more than 10 hours shall be retested for moisture content. A minimum of one cubic yard of aggrega te will be removed from the bottom of the storage bin and discarded. A minimum of one cubic yard of aggregate will then be removed and a moisture content sample taken. Plants that employ moisture probes shall have them calibrated and verified a minimum of 24 hours prior to batching or as directed by the Structural Concrete Engineer. The procedure for checking the meter will be to run aggregate over the probe and then collect a portion of the aggregate on which to perform a moisture content test. If the dif ference between the meter and the tested moisture content is greater than 0.5%, then the meter shall be calibrated.

5-18 All dispensers shall include visual inspection aids such as graduated transparent cylinders.

A separate dispenser shall be provided for each liquid admixture. If the dispensing system does not provide visual inspection aids, then periodic verification tests shall be done at a frequency satisfactory to the Structural Concrete Engineer. Calibration and verification records shall be kept at the production facility for a minimum of one year. The producer shall perform the calibration and verification of the metering systems when re quested. Storage and dispensing systems for liquid admixtures shall be equipped to allow thorough circulation and agitation of all liquid in the system. This shall be required prior to the first batching of concrete for Agency projects in any calendar yea r and periodically thereafter at intervals not to exceed 60 calendar days for the duration of the period the plant is supplying concrete for Agency projects. If the plant has received a delivery of at least 25% of the volume of the storage container, this will be considered as a method of circulation or agitation. If the circulation method is used, the admixture shall be circulated until a complete exchange of admixture is achieved. If an agitation method is used, the method shall be subject to approval by the Structural Concrete Engineer. If an admixture does not need agitation, then the admixture manufacturer shall submit a written statement annually indicating that agitation is not required. Storage and dispensing systems for liquid admixtures shall be maintained within the manufacturer’s stated temperature and environmental conditions. It shall be the responsibility of the Contractor to use the quantity of Agency -approved admixtures needed to obtain concrete meeting the requirements of the Contract. Al l admixtures shall be approved by the Structural Concrete Engineer prior to incorporation into the mix.

5-19 501.05 Mixing and Delivery .

5-20 (3) Addition of water or admixtures at the project site shall be communicated to field

inspection personnel. If additional mixing water , admixtures, or other additions are required, a minimum of 30 revolutions of the mixer drum at mixing speed shall be require d before discharge of any concrete. If water is added in excess of the specified maximum W/CM ratio, the concrete shall not be used.

5-21 The time is valid provided that mixer efficiency tests prove the concrete is satisfactory for

uniformity and strength. The plant shall be equipped with a timing device that will not permit the batch to be discharged before the predetermined mixing time has elapsed. Vehicles used in hauling shall comply with the requirements of Subsection 501.05(c) .

5-22 (2) When silica fume is blended with cement or a combination of cement and mineral

admixture at the cement plant prior to being delivered to the concrete plant, each batch of concrete shall be mixed for not less than 70 nor more than 100 revolutions of the drum or blades at the rate of rotation designated by the manufacturer of the equipment as the mixing speed. The mixing and agitating speeds sha ll be found on the metal plate on the mixer. If inconsistent test results are obtained, or the batch of concrete appears not to be completely mixed, the mixing revolutions shall be extended as necessary. When a transit mixer or agitator is used for transporting concrete, mixing during transport shall be continuous and at two to six rotations per minute or as designated by the manufacturer of the equipment as agitating speed. Failure to do so will be cause for rejection of the concrete. Transit mixers and agitators assigned to a project shall not be used for other purposes until the desired work is completed at the site and shall arrive at the project within the cycle that anticipated placement conditions dictate. The interval between loads shall be co ntrolled such that concrete in place shall not become partially hardened prior to placing succeeding batches. The plant capacity and transportation facilities shall be sufficient to ensure continuous delivery at the rate required. Before discharging concre te from a transit mixer that has been operating at agitating speed, the drum or blades shall be rotated approximately one minute at mixing speed. The same procedure shall apply to agitators. Upon dischar ge of the concrete from the drum, a sufficient amount of water shall be charged into the drum to properly cleanse the drum. This water shall not be used as a part of the next succeeding batch but shall be discharged from the drum prior to the charging of t he drum with the concrete ingredients. The drum shall be completely emptied before receiving materials for the succeeding batch. Re -tempering of concrete or mortar that has partially hardened, by remixing with or without additional materials, shall not be permitted. 501.06 QUALITY CONTROL . The Contractor shall provide assistance, equipment, materials, and curing for field sampling and testing as required by the En gineer. All costs shall be included in the Contract unit prices under Section 631 . The Engineer shall perform all acceptance sampling and testing in accordance with the Agency’s Quality Assurance Program . The Contractor shall perform all on -site quality control (QC) sampling and testing. The person performing the QC sampling and testing shall have, as a minimum, current ACI Concrete Field Testing Technician Grade I Certification.

5-23 (a) Trial Pour . When concr ete will be used for a deck or overlay, or when deemed necessary by the

Engineer, the Engineer may require the Contractor to construct a slab to be used for the trial pour. The purpose of the trial pour is to ensure that the mix can be placed and finished in accordance with these specifications. The concrete slab shall be 10 feet × 10 feet × 9 inches thick, unless otherwise directed by the Engineer. If the concrete is intended to be placed by pump, the trial pour concrete shall be placed by pump. The pump will be set up in the configuration that best represents the most difficult pumping condition. The wet concrete properties will be checked at the point of placement. The Contractor will demonstrate that they can provide an acceptable finish to the concrete for the element to be completed. The Contractor will need to bull float a minimum of 50% of the surface area of the slab and hand finish the curb areas in the same manner as anticipated during the production pour. The Contractor may elect to construct the slab so that the same screed equipment and same finishing method can be used as anticipated for the production pour. In this case the Contractor will not be required to bull float a minimum percentage of surface area unless that will be inclu ded in their process for finishing the concrete deck surface during the deck pour. The test slab will become the property of the Contractor and removed from the project after completion of the trial pour. Concrete production activities shall be closely mo nitored to ensure that no deviations are made from the approved mix design. If test results indicate a failure to obtain the characteristics as specified in Table 501.03A , the Engineer may reject the material. The Contractor will be responsible for proposi ng solutions which could include changes to the mix design and will require testing be done with no extra payment. The modified mix design shall not be used until successful test results are obtained during a trial pour that is representative of the antici pated pour conditions.

5-24 (2) Beginning of Load Sampling . Beginning of load sampling is sampling for QC testing

purposes that is taken before 15% of the load has been discharged. Beginning of load sampling shall be performed as required by the Engineer, or as needed to ensure that the concrete meets the Contract requirements at the point of placement. The QC personnel shall monitor the placement operation and adjust the mix accordingly to ensure that the material being incorporated into the work meets Contract requirements.

5-25 b. Job Control Testing . Job control testing uses specimens to determine whether

adequate curing procedures are being followed and for early form removal or early loading of structure.

5-26 c. Specimen Curing Requirements . Specimen curing requirements shall be as stated

in the specifications or as directed by the Engineer. If not specifically stated, the curing shall be as specified in Table 501.06A . TABLE 501.06A – CONCRETE SPECIMEN CURING REQUIREMENTS Testing Category Number of Specimens Curing Location Acceptance See the Materials Sampling Manual Curing box Job control 2 per test On structure

5-27 (2) Heating of Materials . The heating equipment deployed for cold weather concrete

placement shall be capable of h eating the materials uniformly. Aggregates shall not be heated to a temperature exceeding 150°F. If water is heated to a temperature exceeding 140°F, the water shall be mixed with the aggregate before the cementitious material is added. The materials shal l be heated in such a manner, for such a period of time, and in such quantity, as to produce concrete having a uniform temperature within the specified temperature range at the time of placement. Materials containing frost or frozen lumps shall not be used . Stockpiled aggregates may be heated using dry heat or steam. Aggregates shall not be heated directly by gas or oil flame , or on sheet metal over a fire. When aggregates are heated in bins, steam -coil or water -coil heating, or other methods that will not be detrimental to the aggregates, may be used.

5-28 When the temperature readings taken on or in the concrete indicate the temperature of the

concrete may fall below 50°F, the Contractor shall, without exposing the concrete, immediately build the necessary enclosures around the area involved and supply heat to ensure curing conditions as specified in Subsection 501.15 . The enclosure shall be removed when directed by the Engineer.

5-29 On each recorder chart or file, the Contractor shall indicate the location of the

representative concrete, the placement date, and start and finish times of the temperature record. At the completion of the curing period, the recorder charts shall be submitted to the Engineer. A thermometer shall be provided that is capable of displaying the current ambient temperature with a maximum gradation of 1°F. The inspector will use the thermometer to take periodic temperature measurements of the enclosure at varying locations. The Contractor shall provide a hand -held infrared thermometer capable of taking no - contact measurements that is accurate within plus or minus 2% of the reading. The thermometer’s accuracy shall be certified once every 12 months, with the certificate provided with each thermometer. When the Con tractor places concrete at more than one location within the specified curing period or if the Engineer determines that monitoring of a single pour is necessary in multiple locations, additional monitoring and recording equipment shall be furnished to provide temperature records at each location. 501.08 FORMS . The Contractor shall be responsible for, and shall make good, any injury arising from inadequate forms. The Engineer shall be provided with the opportunity to inspect all forms prior to concrete placement. Unless the Plans specifically allow for the use of stay -in-place forms, such forms shall not be used in the construction of any superstructure or bridge deck. Stay -in-place forms will only be allowed as approved by the Engineer.

5-30 Falsework and forms for slabs, beams, and girders shall be constructed to provide the camber

shown on the Plans or ordered by the Engineer. Falsework and forms for Class SCC concrete construction shall be designed with co nsideration given to concrete placement rates, mix temperature, additives, and placement procedures that affect hydrostatic pressure of the concrete. Forms shall be water -tight and sufficiently rigid to prevent distortion due to the pressure of the concret e and other loads incidental to the construction operations, including vibration.

5-31 All bolt and rivet heads shall be countersunk. Clamps, pin s, or other connecting devices shall be

designed to hold the forms rigidly together and to allow removal without injury to the concrete. Metal forms that do not present a smooth surface or do not line up properly shall not be used. Care shall be exercised to keep metal forms free from rust, grease, or other foreign matter.

5-32 (2) Design Requirements . The following requirements shall govern the de sign of SIPCMF:

5-33 b. Handling and Installation . Care and protection shall be given the metal form sheets,

supports, and accessory items during handling, shipping, and storage. During loading, hoisting, and u nloading operations, extra precautions and care shall be taken to prevent damage to ends, corners, and edges of form sheets, supports, and accessory items. If the form units and accessories are to be stored prior to installation, they shall not be placed in contact with the ground and shall be adequately covered or protected to keep them dry. Form supports shall be placed in direct contact with the flange of the beam, girder, stringer, or floor beam. All attachments shall be made by permissible welds, bol ts, clips, or other approved means. The welding of form supports to steel not considered weldable or to portions of flanges subject to tensile stresses shall not be permitted. Welds and welding shall be in accordance with the requirements of Subsection 506 .10, with the exception that a 1/8 -inch fillet weld will be permitted. Form sheets shall not be permitted to rest directly on the flanges. They shall be securely fastened to form supports by self -tapping screws and shall have a minimum bearing length of 1 inch at each end. Transverse construction joints shall be located at the bottom of a valley. A 1/4 inch diameter weep hole shall be drilled at the lower end of each flute or valley. Screed and pouring runway supports shall not be located directly on the form sheets, form supports, or reinforcing steel. No loose sheets or miscellaneous hardware shall be left on the structural slab at the end of the working day. The corrugated metal sheets shall be fabricated for the placement sequence used, with the joint s between sections of sheets overlapped or securely fastened to eliminate differential deflections. Any exposed form metal where galvanizing has been damaged shall be cleaned and repaired to the satisfaction of the Engineer.

5-34 If the concrete mix or the construction procedures are varied significantly within a

pour, such as a change in the extent of vibration or change in the workability of the mix, another section of forming shall be removed to verify that the new procedures are y ielding desirable results.

5-35 501.09 Placing Concrete .

5-36 (c) Placement Limitations . All concrete shall be placed in daylight, unless otherwise authorized in

writing by the Engineer. Authorization to place concrete at any other time shall not be given unless an adequate lighting system is provided prior to beginning the concrete placement operations. Concrete shall not be pla ced under adverse environmental conditions that the Engineer determines will interfere with acceptable placement or finishing operations. Concrete shall not be placed until the depth and character of the foundation, the apparent adequacy of the forms and falsework, and the placing of the reinforcing steel have been approved by the Engineer. The interior of the forms shall be clean of all debris before concrete is placed. The Contractor shall submit to the Engineer a schedule of batching, delivery, and pla cement prior to the beginning of the concreting operations. The Contractor shall comply with the requirements of Subsection 501.05 . For deck pours, the Contractor shall submit the required retarder schedule to the Engineer a minimum of 3 working days in advance of the placement. The retarder schedule shall demonstrate how the Contractor will ensure that concrete will remain plastic unt il the deck is fully placed. The retarder schedule shall include considerations for the maximum time between batching and discharge, duration of the pour, weather, possible delays, and any other factors that may impact the time to initial set. Equipment and tools necessary for handling materials and performing all parts of the work shall meet the approval of the Engineer as to design, capacity, and mechanical condition and shall be on the site before the work is started. Any equipment, in the ju dgment of the Engineer, that proves inadequate to obtain results prescribed shall be improved or new equipment substituted or added. The Engineer may suspend the pour or reject the pour if the Contractor deviates from the accepted pour plan which will als o include unacceptable delivery rates. The Contractor will not be allowed compensation due to the pour being suspended or rejected due to the Contractor deviating from the accepted pour plan or uncontrolled delivery rates. For simple spans, concrete shall be deposited by beginning at the lower end of the span and working toward the upper end. For continuous spans, where required by design considerations, the concrete placing sequence shall be as shown on the Plans. Concrete shall not be deposited in the forms more than 4 feet from its final position. The dropping of unconfined concrete more than 5 feet will not be permitted.

5-37 Concrete shall not be deposited in running water.

The rate of placing the concrete shall be so regulated that no excessive stresses are placed on the forms. Concrete in all decks shall be placed in one continuous operation, unless otherwise specified. Concrete shall be placed in continuous horizontal layers, the thi ckness of which shall not exceed 18 inches, unless otherwise directed by the Engineer. Each succeeding layer shall be placed before the underlying layer has taken initial set and shall be consolidated in a manner that will eliminate any line of separation between the layers. When it is necessary, due to any emergency, to place less than a complete horizontal layer at one operation, such layer shall terminate in a vertical bulkhead. After the concrete has taken its initial set, care shall be exercised to av oid jarring the forms or straining the ends of projecting reinforcing bars.

5-38 Vibrators shall be manipulated to work the concrete thoroughly around the reinforcement and

imbedded fixtures and into corners and angles of the forms to produce surfaces free of imperfections. Vibrators shall not be used to cause concrete to flow or run into position in lieu of placing. The vibration at any point shall be of sufficient duration to accomplish consolidation but shall not be prolonged to the point where segregation occurs. Vibrators shall have non -metallic or r ubber -coated heads. Vibrating machines shall at no time be left running unattended in the concrete. When it is necessary due to an emergency to discontinue the placing of a monolithic section, the use of vibrators shall cease. Vibrators shall not again be used until a sufficient depth of fresh concrete is placed to prevent any possibility of the effect of vibration on the concrete already in place and in no case shall this depth be less than 2 feet. The number of vibrators used shall be ample to consolida te the incoming concrete immediately after it is deposited in the form. The Contractor shall have at least one spare vibrator in serviceable condition at the site of the structure in which more than 25 cubic yards of concrete are to be placed. The vibrators shall be capable of transmitting vibration to the concrete at frequencies of not less than 4,500 impulses per minute under load. The vibration shall be of sufficient intensity and duration to cause plasticity, settlement, and complete consolidati on of the concrete without causing segregation. The vibrator shall visibly affect a mass of concrete of 2 -inch slump over a radius of at least 18 inches. Unless otherwise specified, Class SCC concrete shall not be consolidated with mechanical vibrators. If the Engineer requests the use of a vibrator, it shall be of an approved type and design, operating within the concrete. To avoid segregation of the concrete, it shall be used as little as possible.

5-39 The anti -washout admixture is not required to be incl uded in mix qualification testing. If the anti -

washout admixture is not included in the mix design for qualification testing, an administrative submittal with the addition of the anti -washout admixture to an approved mix design shall be submitted in accord ance with Subsection 501.03 .

5-40 501.11 PUMPING . Where concrete is conveyed and placed by mechanically -applied pressure, the

equipment shall be suitable in kind and adequate in capacity for the work. The pump shall be capable of pumping concrete within the specified slump limits. The use of aluminum pipe as a conveyance for the concrete will not be permitted. The operation of the pump shall be such that a continuous stream of concrete without air pockets is produced. When pumping is completed, the concrete remaining in the pipeline, if it is to be used, shall be ejected in such a manner that there will be no contamination of the concrete or separation of the ingredients. The equipment shall be arranged so that no resulting vibrations may damage fres hly placed concrete. 501.12 CONSTRUCTION JOINTS .

5-41 501.13 EXPANSION JOINTS . All expansion joints shall be constructed according to the details shown

on the Plans.

5-42 (2) Aesthetic Finish . In addition to the requirements for a dressed finish, the following work

shall be performed when an aesthetic finish is specified. On all exposed surfaces, the cavities produced by form ties and all other holes, honeycomb spots, broken corners or edges, and other minor defects shall be thoroughly cleaned, saturated with water, and carefully pointed and trued with a mortar composed of the same cement and fine aggregate and mixed in the same proportions used in the concrete being finished, unless otherwise directed by the Engineer. Mortar used in pointing shall be not more than 1 hour old. The mortar patches shall be cured for a minimum of 72 hours in accordance with Subsection 501.15 .

5-43 Approval of their methods and equipment does not relieve the Contractor of full

responsibility for obtaining the required surface finish. Prior to te xturing, the finished concrete surface shall be examined by the Contractor. Surface irregularities greater than 1/8 inch in 10 feet in either the longitudinal or the transverse direction shall be corrected in a manner acceptable to the Engineer. When a bituminous concrete surface is to be placed on a bridge deck, the deviation shall not be greater than 1/4 inch. When a sheet membrane is being applied, sharp ridges shall not be allowed. Thin mortar or laitance, which may have accumulated ahead of the finishi ng machine screed, shall be removed from the work site. These materials shall not be used to fill depressions. If the bridge deck concrete does not meet the above smoothness requirements, the Contractor shall remove high spots up to 1/2 -inch high by means of grinding. Any other corrections shall be made only with the written approval of the Engineer. The use of bush hammers will not be allowed. No concrete shall be removed that will result in a concrete slab thickness less than that shown on the Plans. Any deck that cannot be corrected by a method satisfactory to the Engineer shall be removed and replaced at the Contractor’s expense. Sidewalks shall receive their final finish with a fine bristled broom.

5-44 The drag shall produce a transverse, skid -resistant micro -texture acceptable to the

Engineer, but s hall not tear the surface. If the drag is not producing an acceptable micro - texture, the Contractor shall adjust the means and methods until an acceptable micro - texture is achieved. The Contractor shall check the drag material before the deck pour and from ti me-to-time during finishing for tears, worn surface, or hardened concrete. The Contractor shall clean or replace the drag as often as necessary to maintain a well -defined micro -texture. The turf drag or other acceptable methods shall not be applied when t he surface is so wet or plastic that the ridges formed flow back into the valleys when the drag has passed, nor shall dragging be delayed until the concrete is so hard that sharp ridges cannot be formed by the drag. Fogging or similar methods shall be depl oyed to ensure that the surface does not dry prematurely. If the 10 -minute maximum, as specified in Subsection 501.15(c) , for applying the wet cure cannot be met, then fogging of the area shall be performed in a manner that keeps the relative humidity abo ve the evaporation rate of the concrete surface, but not so excessive that water begins to collect on the surface prior to texturing or other surface manipulating procedures.

5-45 (4) Finishing . After the concrete has been placed, it shall be struck off by a finishing machine

and the operation shall be repeated as necessary to produce a uniformly consolidated, dense, smooth surface. The final passage of the finishing machine shall result in a uniform surface at the required grade and slope over its entire area. Finishing machines shall be kept in true adjustment. Machines shall not be used until the proper adjustments have been made and the adjustments have been checked and approved by the Engineer. Sufficient time shall be provided prior to beginning concreting operations for the finishing machin e to be operated over the full length of the bridge deck segment to be placed. This test run shall be made with the screed adjusted to its finishing position. While operating the finishing machine in this test, the screed rails shall be checked for deflect ion and proper adjustment, the cover on slab reinforcement shall be measured, and the controlling dimensions of slab reinforcement and forms shall be checked. After the concrete is placed, it shall be struck off by one of the following methods:

5-46 In areas that are inaccessible to finishing machines, an approved manual vibrat ory-

equipped power screed with an approved grade -control method may be used with approval from the Engineer. Smoothness shall be checked as specified in Subsection 501.14(d)(1) to ensure a smooth ride and seamless transition to the finishing machine’s fini shed area. If manual vibratory -equipped power screeds are used, then initial vibration of the concrete for consolidation in those areas shall be of the minimal duration possible to avoid over - vibration and loss of air entraining of the surface concrete in these areas. Hand finishing will be allowed only in areas inaccessible to finishing machines or manually driven vibratory -equipped power screeds. Hand screeds or bull floats shall be magnesium and at least 10 inches in width. Care shall be taken not to ov erwork the concrete surface during any finishing operation. Smoothness shall be checked as specified in Subsection 501.14(d)(1) to ensure a smooth ride and seamless transition to the finishing machine’s finished area. 501.15 CURING CONCRETE .

5-47 Concrete components shall be cured for the times specified in Table 501.15A .

TABLE 501.15A – CURING TIMES FOR CONCRETE COMPONENTS Type of Construction Curing Methods Effective Cure Time (Days) Substructure Subsection 501.15(b)(1) , (2), (3), (5), (7), and (8) 7 Superstructure Subsection 501.15(b)(2) and (8) 7 1 Retaining walls Subsection 501.15(b)(1) , (2), (5), (6), and (8) 7 Headwalls Subsection 501.15(b)(1) , (2), (5), (6), and (8) 7 Sidewalks, curbs, and gutters Subsection 501.15(b)(2) and (8) 7 1 There shall be no activity on the superstructure during the cure period.

5-48 (5) White Burlap -Polyethylene Sheeting . The entire exposed surface of the concrete shall be

covered with a blanket of white burlap -polyethylene sheeting. The burlap shall be thoroughly dampened prior to placing and shall be placed next to the concrete. All joints shall be lapped a minimum of 18 inches. The burlap shall be kept damp throughout the curing period.

5-49 (c) Bridge Decks . For bridge decks, the curing method shall promptly follow the screed machine,

within a maximum lag time of 10 minutes a nd without interruption. If this lag time cannot be met, then fogging of the area shall be performed in a manner that keeps the relative humidity above the evaporation rate of the concrete surface, but not so excessive that water begins to collect on the surface prior to texturing or other surface manipulating procedures. 501.16 LOADING OF CONCRETE . After the concrete has been placed and the finishing operations concluded, it shall not be walked on or distur bed in any manner, including removal of forms, for a minimum period of 18 hours. If retarder is used as an admixture, this minimum period may be extended as directed by the Engineer.

5-50 501.17 METHOD OF MEASUREMENT . The quantity of Performance -Based Concrete, Class PCD ;

Performance -Based Concrete, Class PCS ; and Performance -Based Concrete, Class SCC to be measured for payment will be the number of cubic yards of the class of concrete specified in the complete and accepted work, as determined by the prismoidal method using dimensions shown on the Plans or as directed by the Engineer. The quantity of concrete shall exclude the volume of steel or other stay -in-place forms and form filling materials. No deductions will be made for the volume of concrete displaced by steel reinforcement, structural steel, expansion jo int material, scuppers, weep holes, conduits, tops of piles, scoring, chamfers or corners, inset panels of 1 -1/2 inches or less in depth, or any pipe less than 8 inches in diameter. If a trial pour is performed at the request of the Engineer, the quantity of concrete to be measured for payment will be the number of cubic yards of the class of concrete specified for the trial pour, as determined by the prismoidal method using dimensions specified in the Contract or as directed by the Engineer. 501.18 BASIS OF PAYMENT . The accepted quantity of Performance -Based Concrete, Class PCD ; Performance -Based Concrete, Class PCS ; and Performance -Based Concrete, Class SCC will be paid for at the Contract unit price per cubic yard. Payment will be full compensation for performing the work specified, including designing the mix, performance of trial pours, and satisfactory finishing and curing. Payment will also be full compensation for furnishing all forms, materials, including joint filler and bond breaker, labor, tools, admixtures, and equipment, including automatic temperature recording units, trial batches, and incidentals necessary to complete the work. The cost of heating materials and protecting the concrete against cold weather, and any additional cost for cement, will not be paid for separately but will be considered incidental to the Contract unit prices for the applicable concrete pay items. The cost of furnishing testing facilities and supplies at the batch plant and the setting of inserts, benchmarks, and bridge plaques furnished by the Agency will not be paid for separately but will be considered incidental to the Contract unit prices for the applicable concrete item. Costs for all materials, labor, and incidentals for steel or other stay -in-place forms and form filling materials will not be paid for separately but will be considered incidental to the Contract unit prices for the applicable concrete item. Payment will be made under: Pay Item Pay Unit 501.3700 Performance -Based Concret e, Class PCD ................................ ................ Cubic Yard 501.3800 Performance -Based Concrete, Class PCS ................................ ................. Cubic Yard 501.3900 Performance -Based Concrete, Class SCC ................................ ................ Cubic Yard

5-51 Section 502 – Shoring Superstructures

502.0 1 DESCRIPTION . This work shall consist of furnishing the necessary shoring, or vertically jacking of any structure or bearing to a position immediately above its present location, holding it in position during any construction process, lowering it to its supports, removing all shoring or falsework, and cleaning up the site. 502.0 2 CONSTRUCTIO N DRAWINGS . Construction drawings shall be submitted in accordance with the requirements of Subsection 105.06 . The Contractor shall submit the drawings and associated calculations, procedures, and details a minimum of 28 days prior to the anticipated start of work. 502.0 3 CONSTRUCTIO N REQUIREMENTS . Associated details, procedures, and calculations for shoring and jack ing shall conform to the requirements of the AASHTO LRFD Bridge Design Specifications and AASHTO LRFD Bridge Construction Specifications . The Contractor shall be responsible for the strength, capacity, and performance of the construction methods employed. When components or materials that are not otherwise specified for removal are removed from the structure during shoring operations and the components or materials are to be re -installed in the construction, the components or materials shall be ca refully removed and salvaged by the Contractor. Components or materials to be retained and re -installed shall be stored at the location specified in the Contract or as directed by the Engineer. The Contractor shall take every precaution necessary to prevent damage to remaining components or materials and those to be retained for re -installation. Damage to remaining structure components or materials and to those to be re -installed shall be repaired or replaced by the Contractor both to the satisfaction of the Engineer and at no additional cos t to the Agency. 502.0 4 METHO D OF MEASUREMENT . The quantity of Shoring Superstructure to be measured for payment will be on a lump sum basis for each location in the complete and accepted work specified in the Contract or o rdered by the Engineer. Unless otherwise specified in the Contract, all work for removing, salvaging, stockpiling, and re -installing existing structure components or materials during the Contractor’s shoring operations will not be measured for payment but will be considered incidental to Shoring Superstructure.