for Highway Construction Page 445 of 71 5 SECTION 578 – PRECAST CONCRETE CULVERT
578.01 Description.
Provide a precast concrete culvert , including the design, f abrication, transportation to the project site, and installation. The precast culvert includes the precast culvert sections and precast components for edge beams, wing walls, cut -off walls, and apron slabs as required. Cut -off walls, ed ge beams, footi ngs, wing walls, and apron slabs may be cast -in-place at no additional cost upon approval. Upon approval of the shop drawings, prepare and submit a structure load rating in accordance with the Idaho Manual for Bridge Ev aluation.
A.Qualifications. Provide current documentation that ensures the precast concrete manufacturer holds current certification under the NPCA Plant Certification Program, the ACPA Q -Cast Plant certification p rogram, or PCI Plant Certification Program.
B.Submittals. Submit the precast manufacturer’s shop drawings and design computations, as specified in 105.02, for approval before fabrication of the precast concrete culvert and components. Follow the requirements of
578.01 C. Ensure the shop drawings and design computations are sealed and signed by an Idaho licensed
professional engineer. Ensure shop drawings include the following:
1.Layout.
2.Station/offset reference points for installation.
3.Precast unit locations.
4.Fabrication details.
5.Lift locations.
6.Reinforcement .
7.Connection details.
8.Dimensions.
9.Details of future utility conduits. Ensure the plan view layout of the precast culvert and culvert components for edge beams, wing walls, cut - off walls, and apron slabs closely resembles the plan view layout s hown. Submit proposed culvert or component layout changes for approval . Submit connection details for approval. Do not begin the construction of any precast units until the design calculations and shop drawings have been approved. Submit the electronic as -built shop drawings before contract closeout.
C.Design. Design the precast concrete culvert and components in accordance with the current edition of the AASHTO LRFD Bridge Design Specifications and the Department’s Bridge Design LRFD Manual. Design all portions of the culvert for the design loads specified. Determine design loads related to fill depth. Footing resistance is included in the Phase IV report. for Highway Construction Page 446 of 71 5 578.02 Materials. Meet the requirements specified in 502. Meet the reinforcing steel requirements specified in 503. Provide reinforcing steel meeting AASHTO M 31, Grade 60. Welded wire reinforcement is allowed if it meets the requirements of 708.02 or ASTM A497. Welded wire reinforcement will be accepted based on the manufacturer’s certification. Provide grout for precast joints as specified in 705.02, Type B, Class 1. Provide drainage geotextile for wing wall connection to culvert barrel as specified in 718.05, Type II.
578.03 Construction Requirements.
Design and provide plans and details for a precast concrete culvert as spe cified. If different sections are designed to accommodate varying depths of fill along the length of the culvert, use the same interior opening dimensions so the interior faces of adjacent segments are smooth and flush. Acceptable culvert shapes and dimensional requirements are specified. Ensure that dimensional tolerances meet ASTM C1577, Section 12. Construct concrete and metal reinforcement as specified in 502 and 503. Precast culverts include an edge beam and may include a cut -off wall at each end of the barrel section. The edge beam may be cast -in-place as a secondary cast on the end- precast segment or it may be cast monolithically with the end- precast segment. Wing walls may be precast or cast- in-place. If precast wings are used, a leveling course of granular material at least 2 inches thick must be placed under the footing where rock is encountered. Provide future utility conduits through the top slab as specified. Install the conduits in the same general location as specified. Conduits must be polyvinyl chloride (PVC) pipe , schedule 40 or heavier. Solvent -weld PVC joints . Cap open ends of conduits. Prove conduits by blowing a pull string from end- to-end of each conduit . Leave the pull strings in place unless otherwise directed. Provide at least 4 inches of fill over the top of the slab for buried culverts. Apply a waterproof membrane as specified in 511 to the top slab of all buried culverts. Use waterproof membrane Type D when ballast and asphalt pavement are placed across the culvert . Use waterproof membrane Type E when only asphalt pavem ent is placed across the culvert. Construct precast culvert joints soil-tight in accordance with the manufacturer’s written requi rements. Provide 12-inch wide joint wrap material that meets ASTM C877. Ensure joint sealant meets ASTM C990. Include joint sealant and joint wrap with each culvert joint. For box culverts, install joint sealant on all 4 sides of the joint. For stiffleg culverts, install joint sealant on all 3 sides of the joint. Wrap the outside face of the joint continuously from the bottom of one wall, up and over the top slab, and down the opposite wall with a single length of wrap. The Engineer will not allow splices in joint wrap. If required by the manufacturer to produce a wat ertight joint, fill joint gaps with non -shrink grout . Connect stiffleg culvert barrel sections using weld plates as specified. Connection of precast components to the barrel section of culverts must not be done using welded plates. Store the precast culvert at the precast manufacturer until delivery to the project s ite. Install the precast culvert to the lines and grades as specified and approved shop drawings . for Highway Construction Page 447 of 715 Connect the precast elements together as specified on the approved shop plans .
578.04 Method of Measurement.
The Engineer will measure acceptably completed work by the lump sum.
578.05 Basis of Payment .
The Department will pay for accepted quantities at the contract unit price as follows: Pay Item Pay Unit Precast Concrete Culvert ........................................................................ LS for Highway Construction Page 448 of 715 SECTION 579 – BON D REINFORCING STEEL
579.01 Description.
Drill and bond reinforcing steel as specified using an epoxy -resin based bonding system.
579.02 Materials.
Provide adhesive as specified in 720.04. Use Type IV, Grade 3 bonding system classification. Meet AASHTO M 31, Grade 60 requirements for reinforcing steel . Submit certified test results for the proposed product for approval before use. The Department has verif ied and approved the following products meet the requirements of bond reinforcing steel :
1.Unitex® Pro -Poxy™ 300 from Dayton Superior.
2.Hilti HIT -RE 500® from Hilti, Inc.
3.Simpson Set Pac Epoxy from Simpson Strong- Tie Company, Inc. Other products will need to be approved before use. This list is for information only and other products may be submitted for approval. Time associated with testing and verifying additional product(s) meet the requirements is not compensable.
579.03 Construction.
Follow the manufacturer's written instructions regarding mixing, drill- hole diameter and depth, application, and curing temperatures and conditions. Size the holes to fully develop the deformed bar. Clean and clear the holes of debris before a dhesive placement . If necessary, adjust the reinforcing steel embedment depth specified to meet development length requirements of the bonded bar. Ensure the pullout strength of the bonded reinforcing steel exceeds the yield strength of the deformed bar. Adjustments to embedment depth will be at no additional cost to the Department.
579.04 Method of Measurement.
The Engineer will measure acceptably completed work as lump sum.
579.05 Basis of Payment .
The Department will pay for accepted quantities at the contract unit price as follows: Pay Item Pay Unit Bond Reinforcing Steel ........................................................................... Lump Sum
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 481–483 of 768.