5-327 SECTIO N 543 – CONTRACTOR -FABRICATE D PRECAS T CONCRET E STRUCTURE 543.0 1 DESCRIPTION . This work shall consist of manufacturing, transporting, handling, and erecting precast concrete structure components fabricated by the Contractor at a location other than a PCI or NPCA certified precast concrete facility. 543.0 2 MATERIALS . Materials sh all meet the material requirements specified in Subsection 501.02 , Subsection 507.02 , and Subsection 540.02 . Concrete shall meet the material requirements specified in Subsection 540.05 . 543.0 3 GENERA L FABRICATIO N REQUIREMENTS . Unless noted otherwise her ein, Contractor - fabricated precast concrete (CFPC) shall meet the requirements of Section 501 , Section 507 , and Section 540. 543.0 4 SUBMITTALS . As soon as practical after award of the Contract, all required information shall be prepared and submitted. Fa brication drawings and erection plans shall be submitted as separate submittals. If the Contractor proposes a different configuration than what is provided in the Plan s then a complete copy of the structural design calculations for the CFPC shall be submitted accompanying the construction draw ings in accordance with Subsection 105.06 . The design calculations shall substantiate that the proposed precast concrete satisfie s the design parameters of the Contract. The applicable design code will be the AASHTO LRFD Bridge Design Specifications unless indicated otherwise in the Contract . Fabrication drawings for the precast concrete shall be submitted in accordance with Subsect ion 105.06 . In addition to the requirements for fabrication draw ings in Subsection 105.06 , the following shall also be included:
a.The concrete mix design in accordance with Subsection 540.04(a) .
b.Dimensions and tolerances of the sections to be fabric ated.
c.The location of reinforcing steel, splices, welded wire fabric, mechanical bar connectors, and inserts. Reinforcing steel material lists, material designations, and bending details shall also be included.
d.The type of concrete surface finish and how the finish will be obtained . 5-328 (e) The concrete curing method, detailing sequence , and duration in accordance with the requirements of Subsection 501.1 5.
f.The minimum required concrete strength for form removal .
g.The design of the lifting attachments, including the minimum required concrete strength to allow lifting. A professional engineer shall stamp calculations. Lifting attachments are not required to be permanently installed in the work and may be removed or left in place at the Contractor’s convenience, provided that the minimum clear cover is met.
h.Transportation, handling, and storage details along with calculations to substantiate the proposed CFPC units will not be cracked or damaged by hand ling or transport. A professional engineer shall stamp calculations.
i.The installation procedures, including a detailed grouting procedure .
543.05 INSPECTION . Materials furnished and the work performed herein shall be inspected by the
Agency. The Agenc y will test all concrete incorporated into the work in accordance with Section 501 . The inspector shall have the authority to reject any material or work that does not meet the requirements of the specifications. Advance notification of at least 14 calendar days shall be provided by the Contractor to the Engineer and the Structural Concrete Engineer c oncerning the proposed intention to commence work. A minimum notification of 5 working day s shall be provided by the Contractor to the Engineer and the Structural Concrete Engineer to confirm the fabrication start date. 543.0 6 FABRICATION .
a.Forming Members . Forms and formwork shall meet the requirements of Subsection 501.0 8.
b.Reinforcing Steel . Bar reinforcement shall be furnished and installed as per Section 507 .
c.Pre-Production Meeting . Unless the Engineer deems, in writing, that a pr e-production meeting is unnecessary, then a pre -production meeting shall be held a minimum of 7 calendar day s prior to beginning concrete placement. At a minimum, t he pre -production meeting shall be attended by the crew supervisor, Contractor project manager, concrete producer, Engineer , Construction Structures Engineer, and Project Manager .
d.Placing Concrete . Concrete placement shall be in accordance with Subsection 501. 09 and as specified herein. Concrete shall not b e deposited in the forms until the appropriate Agency representative has approved placement of the reinforcement, conduits, and anchorages. 5-329 (e) Curing . Curing shall meet the requirements of Subsection 501.1 5.
f.Removal of Forms . Forms shall not be removed until the curing period has ended.
g.Concrete Finishing . Finishing shall conform to the requirements of Subsection 501.1 4.
h.Repairs and Patching . CFPC structure components that contain minor defects caused by manufacture or handling may be repaired at the manufacturing site. Minor defects are defined as holes, honeycombing, or spalls which are 6 inches or less in diameter and that do not penetrate deeper than 1 inch into the concrete. Surface voids or bug holes that are le ss than 5/8 inch in diameter and less than 1/4 inch deep need not be repaired. Repairs shall be made using a material from the Agency’s Approved Products List for overhead and vertical concrete repair. The repair material shall be cured as specified by the manufacturer. Repairs shall be approved by the Engineer.
i.Cracking . Cracks less than 0.01 inch in width shall be sealed by a method approved by the Engineer. Cracks in excess of 0.01 inch may be cause for rejection. At the Engineer’s discretion, cracke d CFPC structure components shall be repaired or replaced at the Contractor’s expense.
j.Dimensional Tolerances . All tolerances shall be in accordance with both PCI MNL -116 and PCI MNL -135, or with the NPCA Quality Control Manual for Precast Concrete , unless otherwise noted in the Contract or as approved by the Engineer.
k.Marking . The date of manufacture, the production lot number, and the piece mark shall be clearly marked on each individual piece of precast concrete. The mark shall be in a location that will not be visible in the finished product.
l.Production Site Handling . Units shall not be lifted, moved, or otherwise disturbed until the curing period is complete and the concrete has reached the minimum compressive strength required f or lifting per the approved lifting attachment design. 543.0 7 HANDLING , STORAGE , AND SHIPPING . Each CFPC structure shall be handled, stored, and shipped in such a manner as to minimize chipping, cracks, fractures, discoloration, and excessive bending stresses. A unit damaged by handling, storage, or shipping shall be replaced at the Contractor’s expense. A CFPC structure shall not be installed until the respective unit has been inspected. This inspection shall verify that the pieces are free from defects, and that all specification requirements, including but not limited to those for compressive strength and tolerance requirements, have been achieved. In addition, a CFPC structure will not be considered for shipment until the completion of the cure period a nd the required strength has been attained as demonstrated by field cured cylinder breaks. 5-330 Field cured test cylinders for production site handling and shipping strength verification purposes shall be tested either at the Agency’s Materials Testing and Certification Section Central Laboratory or at an independent laborat ory approved by the Engine er. An Agency representative shall witness all tests. If an independent laborat ory is proposed to be used to test the field cured cylinders, the Contractor shall submit documentation providing verification for the following:
a.That c alibration of the com pression machine has been performed in accordance with ASTM C39, Section 5
b.That the c ompression machine meets the requirements of ASTM C39
c.That the t echnician who will be performing the test is proficient in the test methods The Agency at any time reserves the right to perform an independent proficiency evaluation of the technician for the test methods used and review the testing facility. 543.0 8 INSTALLATIO N METHODS , EQUIPMENT , AND ERECTION . Cranes, lifting devices, and other equipment for CFPC structure erection shall be of adequate design and capacity to safely erect, align, and secure all members and components in their final positions without damage. The Contractor is solely responsible for the methods and equipment employed for the erec tion of the CFPC structure components. Construction drawings for CFPC structure component erection shall be submitted in accordance with Subsection 105.06 . The erection plan shall include the necessary computations to indicate the magnitude of stress in th e units during erection and to demonstrate that all of the erection equipment has adequate capacity for the work to be performed, and provisions for all stages of construction, including temporary stoppages. Post tensioning shall comply with Subsection 540 .12. Submittal of the erection plan is for documentation purposes only and shall in no way be construed as approval of the proposed method of erection. The Contractor shall follow the erection plan as submitted. 543.0 9 GROUT . Grout shall be placed in accordance with the requirements of Subsection 540.11 . 543.1 0 METHO D OF MEASUREMENT . The quantity of Contractor -Fabricated Precast Concrete Structure of the type and size specified to be measured for payment will be on a lump su m basis in the complete and accepted work . The lump sum will include all of the CFPC structure components for each location specified in the Contract. 5-331 543.1 1 BASIS OF PAYMENT . The accepted quantity of Contractor -Fabricated Precast Concrete Structure of the type and size specified will be paid for at the Contract lump sum price. Payment will be full compensation for designing, detailing, fabricating, repairing, transporting, handling, and erecting the materials specified, for furnishing and implementing the erection plan, and for furnishing all labor, tools, equipment, and incidentals necessary to complete the work. Any grouting work, such as fairing out unevenness between adjacent precast concrete structure components and filling leveling screw holes, sh ear keys, transverse anchor recesses, and dowel holes, will be considered incidental to the work for Contractor -Fabricated Precast Concrete Structure. Payment will be made under: Pay Item Pay Unit
543.10 00 Contractor -Fabricated Precast Concrete Structure ................................ ....Lump Sum
5-332 SECTIO N 544 – PREFABRICATE D BRIDG E UNIT SUPERSTRUCTURE 544.0 1 DESCRIPTION . This work shall consist of manufacturing, transporting, and erecting concrete and steel composite Prefabricated Bridge Units (PBUs) as shown on the Plan s. The work under this section shall be performed in accordance with these provisions, the Plan s, and Section 501, Section 506 , Section 507 , and Section 508 . 544.0 2 MATERIALS . Materials shall meet the material requirements specified in Subsection 501.02 , Subsection 506.02 , Subsection 507.02 , and Subsection 508.02 . 544.0 3 GENERA L FABRICATIO N REQUIREMENTS . The structural steel furnished under this section shall be fabricated in a p lant meeting the requirements of Subsection 506.03 . After fabrication, the structural steel shall be transported to a location approved by the Agency where the steel will be shop galvanized , metallized , or painted, or where the remainder of the composite superstructure unit will be fabricated. The fabricator or Contractor constructing the reinforced concrete portion of the PBUs shall have demonstrated experience in forming, casting, curing, and finishing performance -based concrete superstructure decks in accordance with Section 501 . 544.0 4 SUBMITTALS . As soon as practical after award of the Contract, all required information shall be prepared and submitted. Fabrication drawings and erection plans shall be su bmitted as separate submittals. Fabrication drawings for the PBUs shall be submitted in accordance with Subsection 105.06 . In addition to the requirements for fabrication draw ings in Subsection 105.06 , the following shall be included:
a.Structural steel information i n accordance with Subsection 506.04 .
b.Dimensions and tolerances of the sections to be fabricated .
c.The location of reinforcing steel, splices, welded wire fabric, mechanical bar connectors, and inserts . Reinforcing steel material lists, material designations, and bending details shall also be included.
d.The type of concrete surface finish and how the finish will be obtained .
e.The concrete curing method, detailing sequence , and duration in accordance with the requirements of Subsection 501.1 5.
Source: Vermont Standard Specifications for Construction, 2024 Edition. Pages 741–745 of 1,380.