472 Steel reinforcing shall be epoxy coated per AASHTO M -284 or galvanized per AASHTO M-111 for structures installed at an elevation such that the top or crown of the structure is above the bottom of the subgrade in the pavement section.
620.5.3 -Permissible Variations: 620.5.3.1 -Internal Dimensions: The internal dimensions shall not vary from the design dimensions by more tha n 1 percent (1%) or 1-1/2 inches, whichever is less. The haunch dimensions shall vary not more than 3/4 inch from the design dimension.
620.5.3.2 -Slab and Wall Thickness: The slab and wall thickness not be less than that shown in the design by more th an 1/4 inch. A thickness more than that required in the design shall not be cause for rejection.
620.5.3.3 -Length of Opposite Surfaces: Variations in laying lengths of the two opposite surfaces of the culvert shall not be more than 5/8 inch in any bridge/culvert unit, except where beveled ends for laying of curves are specified by the purchaser.
620.5.3.4 -Length of Unit: The underrun i n length of a unit shall not be more than 1/2 inch in any unit.
620.5.3.5 -Position of Reinforcement: The maximum variation in position of the reinforcement shall be + 1/2 inch. In no case shall the cover over the reinforcement be less than 1 -1/2 inch for the outside circumferential steel or be less than one (1) inch for the inside circumferential steel as measured to the external or internal surface of the bridge/culvert unit. These tolerances or cover requirements do not apply to mating surfaces of the joints.
620.5.3.6 -Area of Reinforcement: The areas of steel reinforcement shall be the design steel areas as shown in the manufacturer's shop drawings. Steel areas greater than those required shall not be cause for rejection. The permissible variation in diameter of any reinforcement shall conform to the tolerances prescribed in the ASTM Specification for that type of reinforcement.
620.5.4 -Curing: All Bridge/Culvert units shall be cured in accordance with Section be discontinued once 70% of the design Strength is achieved.
620.5.5 -Testing and Inspection: 620.5.5.1 -Precast Three -Sided Bridge/Culvert Units: 620.5.5.1.1 -Type of Test Specimen: Concrete compressive strength shall be determined from compression te sts made on cylinders or cores. For cylinder testing a minimum of 5 cylinders shall be fabricated during each production day. For core testing, one core shall be cut from a unit selected at random from each group of 15 units or less of a particular size a nd production run. For each continuous production run, each group of 15 units of a single size or fraction thereof shall be considered separately for the purpose of testing and acceptance. A production run shall be considered continuous if not interrupted for more than 3 consecutive days.
473 620.5.5.1.2 -Compression Testing: Cylinders shall be made and tested as prescribed by the AASHTO T 22 and R 100 Specifications. Cores shall be obtaine d and tested for compressive strength in accordance with the provisions of the AASHTO T 280.
620.5.5.1.3 -Acceptability of Cylinder Tests: Each compressive strength test used for acceptance shall consist of the average strength of a minimum of two compressive strength test cylinders fabricated from a single rando mly selected batch of concrete as it is being placed in the forms. Failure of any of the individual 28 day test cylinders to meet 90 percent (90%) of the minimum compressive strength requirement can be cause for rejection. The average of all cylinders com prising a strength test must meet or exceed the design strength.
620.5.5.1.4 -Acceptability of Core Tests: The compressive strength of the concrete in each group of units as defined in subsection 620.5.4.1.1 is acceptable when the core test strength is equal to or greater than the design concrete strength. When the compressive strength of the core tested is less than the design concrete strength, the unit from which that core was taken may be recored. When the compressive strength of the recore is equal to or greater than the design concrete strength, the compressive strength of the concrete in that group of units is acceptable. When the compressive strength of any recore is less than the design concrete strength, the unit from which that core was taken shall be rejected. Two units from the remainder of the group shall be selected at random and one core shal l be taken from each. If the compressive strength of both cores is equal to or greater than the design concrete strength, the compressive strength of the remainder of that group of units is acceptable. If the compressive strength of either of the two cores tested is less than the design concrete strength, the remainder of the group of units shall be rejected or, at the option of the manufacturer, each culvert of the remainder of the group shall be cored and accepted individually, and any of these units that have cores with less than the design concrete strength shall be rejected.
Plugging Core Holes -The core holes shall be plugged and sealed by the manufacturer in a m anner such that the unit will meet all of the test requirements of this specification. Units so sealed shall be considered satisfactory for use.
Test Equipment -Every manufacturer furnishing unit under this specification shall furnish all facilities and personnel necessary to carry out the test required.
620.5.5.2 -Cast -In-Place Three -Sided Bridge/Culvert: Cast-in-place testing and inspection shall be per section 601.
620.5.6 -Joints: 620.5.6.1 -Precast Three -Sided Arch -Topped Bridge/Culvert Units: The bridge/culvert units shall be produced with flat bu tt ends. The ends of the unit shall be such that when the sections are laid together they will make a continuous line of units with a smooth interior free of appreciable irregularities, all compatible with the permissible variations in subsection 620.5.3. The joint width shall not exceed 3/4 inches. The outside edges of the ends of each bridge/culvert unit shall be chamfered. The butt joint made by two adjoining units shall be covered with a piece of preformed bituminous joint sealant and a minimum of a nine (9) inch wide joint wrap.
474 620.5.6.2 –Precast Three -Sided Flat -Topped Bridge/Culvert Units: The bridge/culvert units for flat -topped culverts shall be produced with a minimum four ( 4) inches deep by 1 -1/2 inches wide keyway joint. Shea r key grout in accordance with Section 715.5 shall be placed in the keyway joint. Field Testing of shear key grout shall be performed by the Contractor in accordance with ASTM C109, as modified by ASTM C1107. Compressive strength of the grout as determine d by the average result of three test specimens shall meet the requirements specified in the Contract Plans.
620.5.7 -Workmanship and Finish: The bridge/culvert units shall be substantially free of fractures. The ends of the units shall be normal to the walls and centerline of the unit section, within the limits of the variations given in subsection 620.5.3, except where beveled ends are specif ied. The inside and outside surfaces of the units shall be a smooth steel form finish.
620.5.8 -Repairs: All repairs are to be performed in accordance with subsection 620.10.2.
620.5.9 -Inspection: The quality of materials, the process of manufactur e, and the finished bridge/culvert units shall be subject to inspection by the engineer.
620.5.10 -Rejection: Bridge/culvert units shall be subject to rejection on account of any of the specification requirements. Individual units may be rejected beca use of any of the following:
exceed one half the thickness of the wall.
Section 5.
than ½” diameter and over 1” deep occur.
satisfactory joint. For butt type joints, damaged surfaces greater than 12” long and over 2” deep will be cause for rejection of the units.
deeper than the shear key may be cause for rejection.
620.5.11 -Marking: Each culvert shall be clearly marked by waterproof paint. The following shall be shown on the inside of the vertical leg of the culvert section: Bridge/Culvert Unit Span X Bridge/Culvert Unit Rise Date of Manufacture Name of the manufac turer WV State and Federal Project Number Project Contract Number
620.5.12 -Backfill: Backfill material shall be select material for backfilling in accordance with 626.5.3. Backfilling shall be according to subsection 626.6.1.3. The backfill material is to be placed in a zone with a minimum width that extends to a point located four ( 4) feet outside the base of each leg and with a height being equal to the outside height of the structure plus two feet or the minimum cover, whichever is less. This material is also to be placed to a depth of at least four ( 4) feet behind each wingwall.
475 Additional granular material requirements are the responsibility of the contractor and the bridge/culvert supplier.
620.6 -CONSTRUCTION METHODS : 620.6.1 -Precast Three -Sided Br idge/Culvert: 620.6.1.1 -Footings: The bridge/culvert units shall be installed on cast -in-place concrete footings. The elevation of the bottom of the footing shall be equal to or lower than the elevation as shown on the plans. A keyway for grouting with a minimum depth of three ( 3) inches shall be formed in the top surface of the footing and the keyway shall extend to where three ( 3) inches clear of the inside and outside faces of the bridge/culvert unit, unless specified otherwise on the plans or by the bridge/culvert system supplier. The footings shall be given a rough float finish and shall reach a compressive strength of 2,000 psi before placement of the bridge/culvert units. The completed footing surface shall be constructed in accordance with grades shown on the plans. When tested with a 10 foot straight edge, the top surface of the footings shall not vary more than ¼ inch in ten (10) feet. The foundation is to be constructed in accordance with the approved shop drawings.
620.6.1.2 -Placement of the Bridge/Culvert Units: A representative of the manufacturer shall be present during the first three days the structure is being placed. The units shall be placed as shown on the Engineer’s plan drawings. Special care shall be ta ken in setting the units to the true line and grade. The units shall be set on masonite or steel shims at least five ( 5) inches square, or on a concrete leveling pad cast inside the keyway. When set on shims a minimum of a ½ inch gap shall be provided bet ween the footing and the base of the unit leg. Prior to grouting three sided structures with legs that have a curved exterior surface, the legs shall be supported horizontally using hardwood wedges driven between the outside of the structure leg and the w all of the keyway. The requirements for the grout will conform to subsection 715.5 and testing of the grout shall be performed by the Contractor in accordance with ASTM C109, as modified by ASTM C1107. Compressive strength of the grout shall be at least XXXX psi at X days as determined by the average result of three test specimens. Wedges shall be spaced no more than two (2) feet apart along both sides of the structure.
620.6.1.3 -External Waterproofing: When specified on the plans and the limits of application are shown, a waterproofing membrane as described below shall be applied to the top and the sides of the structure unless the top of the structure is to be the driving surface. The material should be installed per the waterproofer manufacturer’s instructions.
Property Value 1 Test Method Strip Tensile 50 lbs./in. ASTM D8822 Puncture Resistance 200 lbs. ASTM E154 Permeance 0.10 perms (max.) ASTM E96, Method B Pliability No cracks in fabric or rubberized asphalt ASTM D1463 1 Minimum average roll values unless otherwise noted 2 Using 12 in/min test speed and 1” initial distance between grips. 3 Using 180 ° bend on ¼ inch mandrel at -25°F