Precast Concrete Box Culvert and Three- Sided Structures PRECAST CONCRETE BOX CULVERT AND THREE -SIDED STRUCTURE S
Part 1 — General
1.1 Section Includes
A.Single -cell precast concrete box culverts and multi- cell precast concrete box culverts , with waterproofing membrane .
B.Precast concrete three -sided structures with waterproofing membrane and precast , or cast -in-place, elements required along the barrel of the structure.
C.Precast concrete secondary elements associated with the structure.
1.2 Related Sections
A.Section 02056: Embankment, Borrow, and Backfill
B.Section 02317: Structural Excavation and Backfill
C.Section 03055: Portland Cement Concrete
D.Section 03211: Reinforcing Steel and Welded Wire
E.Section 03310: Structural Concrete
F.Section 03390: Concrete Curing
G.Section 03575: Flowable Fill
H.Section 07105: Waterproofing Membrane
1.3 References
A.AASHTO M 111: Zinc (Hot -Dip Galvanized) Coatings on Iron and Steel Products
B.AASHTO LRFD Bridge Design Specifications
C.AASHTO Manual for Bridge Evaluation Precast Concrete Box Culvert and Three- Sided Structures
D.ASTM C 877: External Sealing Bands for Concrete Pipe, Manholes, and Precast Box Sections
E.ASTM C 990: Joints for Concrete Pipe, Manholes, and Precast Box Sections Using Preformed Flexible Joint Sealants
F.ASTM C 1107: Packaged Dry, Hydraulic -Cement Grout (Nonshrink)
G.ASTM C 1504: Manufacture of Precast Reinforced Concrete Three- Sided Structures for Culverts and Storm Drains
H.ASTM C 1577: Precast Reinforced Concrete Monolithic Box Sections for Culverts, Storm Drains, and Sewers Designed According to AASHTO LRFD
I.ASTM C 1786: Segmental Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, and Sewers Designed According to AASHTO LRFD
J.Precast/Prestressed Concrete Institute (PCI) Design Handbook
K.UDOT Bridge Management Manual
L.UDOT Quality Management Plan
M.UDOT Structures Design and Detailing Manual (SDDM)
1.4 Definitions
A.Precast Secondary Element s – Precast e lements attaching to the box culvert or three- sided structure system outside of the main barrel s uch as cutoff walls, aprons, headwalls, wingwalls, return walls and footings .
1.5 Submittals
A.Shop drawings for review
1.Fabrication and Installation
a.Detail all phases of fabrication and construction including layout, joint details, lifting devices, casting methods, and construction placement.
b.Include details for cast -in-place elements that are included in this item of work and are not detailed in the plans .
c.Include excavation, bedding, and backfill requirements .
d.Include joint tolerances.
e.Note proposed transportation methods. Precast Concrete Box Culvert and Three- Sided Structures
2.Include inventory and operating load ratings in a table on the first sheet of the drawings for structures meeting the definition of a bridge.
a.Provide load rating package according to the UDOT Bridge Management Manual and the AASHTO Manual for Bridge Evaluation.
3.Provide the seal of a Professional Engineer (PE) or Professional Structural Engineer (SE) licensed in the State of Utah on the drawings and supporting engineering calculations for the following:
a.Special designs of precast concrete box
b.Precast concrete three- sided structures
c.Foundations for precast concrete three- sided structures
d.Floor slabs of precast concrete three- sided structures
e.Lifting devices
f.Secondary elements
g.Connections between precast and cast -in-place , and precast to precast, members and secondary members
h.Load ratings
i.Other means and methods that require an engineer’s design
B.Certificate of compliance for dry cast concrete for information
C.Manufacturer’s product data sheets and recommended installation instructions for review for the following products:
1.Non-shrink grout
2.Joint sealant
3.Flexible watertight gaskets
4.Joint wrap
Part 2 — Products
2.1 Materials
A.Concrete
1.Wet Cast Concrete
a.Class AAA(AE) according to Section 03055. 1) Provide 28- day minimum compressive strength of 5,000 psi.
2.Dry Cast Concrete
a.Provide 28 day minimum compressive strength of 5,000 psi or as shown in the shop drawings and associated calculations . Precast Concrete Box Culvert and Three- Sided Structures
B.Reinforcing Steel and Welded Wire
1.Coated – Refer to Section 03211.
C.Bedding
1.Granular backfill borrow according to Section 02056
a.Limit soil gradation to 100 percent passing the ¾ inch sieve.
2.Free draining granular backfill when shown according to Section 02056
a.Limit soil gradation to 100 percent passing the ¾ inch sieve.
D.Leveling Course
1.Use gravel or chip l imited to 100 percent passing the 3/8 inch sieve.
E.Flowable Fill
1.Refer to Section 03575.
F.Non-Shrink Grout
1.Refer to ASTM C 1107.
G.Embankment
1.Refer to Section 02056.
2.2 Joint Seal S
A.Use one of the following:
1.Joint sealant
a.ASTM C 990
b.Flexible butyl rubber material with a minimum cross -section of ¾ x 1½ in ches as a joint sealant for box culverts
2.Flexible watertight gaskets
a.ASTM C 1619 , Class C
b.Pre-lubricated by the manufacturer
B.Joint seals are furnished by the precaster .
2.3 Joint Wrap
A.Provide joint wrap at least 2 ft wide. Refer to ASTM C 877.
2.4 Waterproofing Membrane
A.Refer to Section 071 05. Precast Concrete Box Culvert and Three- Sided Structures
2.5 Lifting Devices
A.Use lifting devices that can support the required vertical and horizontal forces with the applicable safety factors as specified in the Component Handling and Erection Bracing requirements of the PCI Design Handbook.
B.Galvanize according to AASHTO M 111.
2.6 Grouted Splice Couplers
A.Refer to Section 03211.
2.7 Manufacture
A.General
1.Use a Department preq ualified concrete precaster for precast concrete box culverts and three- sided structures according to the Department Quality Management Plan: 505 - Precast /Prestressed Concrete Structures .
2.Manufacture precast segments in at least 5 ft lay lengths.
3.Project the reinforcing steel at least 12 inch out of the precast sections or as shown.
4.Square off the concrete face where precast sections join cast -in- place concrete.
5.Do not locate horizontal and vertical changes in alignment greater than 10 degrees at a joint between precast segments of a precast concrete box culvert .
6.Permanently mark each precast segment with date of casting and supplier identification.
7.Cast the Department structure number into the top and exposed faces of the headwall at each end of the structure as shown.
B.Precast Concrete Monolithic Box Culverts
1.Refer to ASTM C 1577 .
2.Provide s pecial designs for sizes and loads other than those shown in Table 1 of ASTM C 1577 if the design is not provided or if load rating is required.
a.Prepare special designs according to the SDDM and the AASHTO LRFD Bridge Design Specifications, Section 12.
b.Provide at least 1 inch concrete cover to reinforcing steel.
c.Provide at least 2 inch concrete cover to reinforcing steel in the top of the top slab when covered by less than 2 ft of fill.
d.Provide tongue and groove ends , or equivalent , to transfer shear between sections at all joints. Precast Concrete Box Culvert and Three- Sided Structures
e.Design and form section ends so that the sections can be laid together to make a continuous line of box sections compatible with the permissible variations in ASTM C 1577.
C.Precast Concrete Segmental Box (Clamshell) Culverts
1.Refer to ASTM C 1786 w ith the following exceptions:
a.Design the structure according to the SDDM and the AASHTO LRFD Bridge Design Specifications , Section 12.
b.Design for HL- 93 live loading.
2.Provide longitudinal wire spacing of no more than 8 inch for welded wire.
3.Provide a circumferential wire spacing not greater than 4 inch or less than 2 inch.
4.Provide at least 2 inch concrete cover to reinforcing steel in the top of the top slab when covered by less than 2 ft of fill.
D.Precast Concrete Three- Sided Structures
1.Refer to ASTM C 1504 for precast concrete three- sided structures with the following exceptions:
a.Design the structure according to the SDDM and the AASHTO LRFD Bridge Design Specifications , Section 12.
b.Design for HL- 93 live loading.
2.Provide longitudinal wire spacing of no more than 8 inch for welded wire.
3.Provide a circumferential wire spacing not greater than 4 inch or less than 2 inch.
4.Provide at least 2 inch concrete cover to reinforcing steel in the top of the top slab when covered by less than 2 ft of fill.
5.Mechanical connections for three- sided structures
a.Mechanically connect the exterior sections of precast three- sided structures at top joints which are within 12 ft from end of the structure. 1) Use at least four mechanical connections per joint with a maximum spacing of 10 ft. 2) Use g alvanize d plates, shapes , and hardware.
b.Connect precast three- sided structures to the footing, pedestal , or slab 2 ft from the outermost exterior edge of the structure at the four corners of the structure 1) Use a galvanized rigid mechanical connection. 2) Locate the connection on the interior face of the segment to allow for future inspection.
E.Precast Secondary Elements
1.Design secondary elements and connections according to AASHTO LRFD Bridge Design Specifications and the SDDM. Precast Concrete Box Culvert and Three- Sided Structures
F.Lifting Devices
1.Provide the number and type of lifting devices required to support the vertical and horizontal forces with the applicable safety factors as specified in the Component Handling and Erection Bracing requirements of the PCI Design Handbook.
a.Limit diameter of holes for lifting devices to 3 inch when used.
b.Locate holes to avoid interference with the reinforcing steel.
G.Concrete Curing – Refer to Section 03390.
H.Quality Control
1.Prevent cracking or damage of precast elements during shipping, handling, and storage.
2.Replace defects and breakage of precast elements.
a.Members that sustain damage or surface defects during fabrication, handling, storage, hauling, or erection are subject to review or rejection.
b.Obtain authorization before performing repairs.
c.Repair work must reestablish the elements ’ structural integrity, durability, and aesthetics to the satisfaction of the Engineer.
d.Determine the cause w hen damage occurs and take corrective action.
e.Failure to take corrective action, leading to similar repetitive damage, c an be cause for rejection of the damaged element.
f.Cracks that extend to the nearest reinforcement plane and fine surface cracks that do not extend to the nearest reinforcement plane but are numerous or extensive are subject to review and rejection.
g.Spalls greater than 1 ft and f ull depth cracking are cause for rejection.
Part 3 — Execution
3.1 Excavating, Trenching, Bedding, and Backfill
A.Refer to Section 02317.
B.Use a trench width adequate to place and compact bedding material.
1.Outside width of trench is the outside width of structure plus at least two feet on each side .
C.Excavate to at least 8 inch below the bottom of the precast structure unless shown otherwise . Precast Concrete Box Culvert and Three- Sided Structures
D.Scarify , moisture condition, and compact the top 8 inch of the excavated ground surface to at least 90 percent of the maximum dry density.
E.Place a bedding of at least 6 inch unless shown otherwise.
1.Level and compact bedding material to provide uniform support of the structure along its entire supported width and length.
F.Place a leveling course of at least 2 inch on top of the bedding.
G.Backfill as shown.
H.Fill the gap between multiple single cell culverts with flowable fill as shown.
3.2 Installation
A.General
1.Follow the authorized shop drawings
2.Establish working points, working lines, and benchmark elevations before placing elements .
3.Remove dirt and foreign material from joints and gaskets .
a.Do not lubricate gaskets.
4.Inspect precast elements for defects before lowering into trench.
a.Repair or replace defective, damaged, or unsound precast elements.
b.Replace damaged gaskets.
5.Place precast elements starting at the downstream end.
a.Do not place precast elements when water is in the trench.
B.Apply joint seal to precast box culvert.
1.Joint sealant
a.Apply joint sealant on the inside of the groove (bell) of the box last placed and on the outside of the tongue (spigot) of the box to be set.
b.Apply joint sealant about 1 inch from the leading edge of the groove and tongue.
c.Maintain the joint sealant at 70 degrees F or greater during placement.
2.Flexible watertight gasket
a.Coordinate with the precaster to reattach gasket if gasket detaches during shipping and handling. Precast Concrete Box Culvert and Three- Sided Structures
C.Placement of Precast Concrete Box Culverts
1.Pull precast box culvert sections together to ½ inch joint gap spacing measured face to face of adjoining concrete surfaces with the joint gap being uniform on all sides of the precast box culvert.
a.Prevent soil from being forced into the joint as the box sections are placed.
b.Disassemble joint , check position of joint sealant, repair alignment, and re- install when adjoining elements cannot be pulled together to meet joint requirements.
c.The Engineer may approve up to a ¾ inch joint gap spacing in cases where it is necessary to adjust the total length of a box culvert run.
d.The Engineer may r eject box sections when the installation tolerance cannot be met due to casting variations.
D.Placement of precast three- sided structures
1.Do not exceed joint tolerances in the authorized shop drawings .
E.Apply joint wrap to the top slab and side walls at joints .
1.Clean top and sides of concrete surface at joints before placing joint wrap.
2.Apply joint wrap at least 2 ft wide and centered on the joint.
F.Install precast secondary elements
1.Clean bonding surfaces between elements of debris, dust, and rust before connecting elements.
2.Place cut-off wall and apron elements as shown.
a.Adjust the final location of the cut -off wall or apron elements if actual joint gaps cause the final location to vary.
b.Adjust the height of each apron element by means of leveling devices or shims.
3.Adjust vertical leveling devices before full release of the apron from the crane to reduce the amount of torque required to turn the bolts in the leveling devices.
4.Place or pump flowable fill into voids and pockets.
5.Connect secondary elements to precast concrete box culvert or three- sided structure as shown in the shop drawings.
3.3 Finishing Recesses From Lifting Holes and Devices
A.Plug lift ing holes and lift ing device recesses with non -shrink grout.
1.Finish flush with adjacent concrete surfaces. Precast Concrete Box Culvert and Three- Sided Structures
3.4 Cast -In-Place Concrete
A.Place and finish concrete according to Section 03310.
B.Cure concrete according to Section 03390.
3.5 Waterproofing Membrane
A.Apply a waterproofing membrane to the full length of the top slab and side walls.
Source: Utah Standard Specifications for Road and Bridge Construction, 2026 Edition. Pages 405–414 of 1,331.