STRUCTURAL CONCRETE
PART 1 GENERAL
1.1SECTION INCLUDES
A.Cast-in-place concrete construction in concrete structures such as
bridges, culverts, and miscellaneous structures.
1.2RELATED SECTIONS
A.Section 02056: Embankment, Borrow, and Backfill
B.Section 02317: Structural Excavation
C.Section 02701: Pavement Smoothness
D.Section 02842: Delineators
E.Section 03055: Portland Cement Concrete
F.Section 03056: Self-Consolidating Concrete (SCC)
G.Section 03057: Structural Concrete - Lightweight
H.Section 03152: Concrete Joint Control
I.Section 03390: Concrete Curing
J.Section 07105: Waterproofing Membrane
K.Section 07921: Sealing Existing Concrete Slope Protection Joints
1.3REFERENCES
A.AASHTO M 111: Zinc (Hot-dip Galvanized) Coatings on Iron and Steel
Products
B.AASHTO LRFD Bridge Construction Specifications Section 3 (Temporary
Works)
C.ASTM C 578: Rigid, Cellular Polystyrene Thermal Insulation
Structural Concrete
D.International Concrete Repair Institute (ICRI)
E.UDOT Quality Management Plans
1.4DEFINITIONS Not Used
1.5SUBMITTALS
A.Working Drawings for review
1.Drawings for Temporary Works
2.Deck Overhang Bracing when shown or when screed rails are
supported on forms.
a.Include supporting calculations.
b.Provide the seal of a Professional Engineer or Professional
Structural Engineer licensed in the State of Utah on drawings and calculations.
B.Concrete Placing and Finishing Plan for review when placing cast-in-place
concrete in bridge decks and approach slabs.
1.Include at least the following:
a.Description of equipment, materials, methods, and personnel
for placing, finishing, and curing concrete
b.Quality control plan
c.Placement schedule for each bridge, including placement
rates, time of day, duration, placement sequence, and placement direction
d.Screed elevations for deck and approach slabs of each
bridge
e.Survey data used to develop screed elevations.
PART 2 PRODUCTS
2.1CONCRETE
A.Bridge Decks, Approach Slabs, and Concrete Diaphragms cast with
bridge decks:
1.Standalone pedestrian, shared use or multi-use overpass or
underpass structures.
a.Use Class AA(AE). Refer to Section 03055.
Structural Concrete
2.Other bridge types.
a.Use Class AA(LSF). Refer to Section 03055.
1) Includes top/bottom slabs and approach slabs of box culverts with traffic directly on the slabs.
3.Use Structural Concrete – Lightweight where shown. Refer to
a.Use the concrete class shown.
4.Use Class AA(ES) only where shown for closure pours with full-
depth precast concrete deck panels. Refer to Section 03055.
B.Concrete Slope Protection:
1.Class A(AE). Refer to Section 03055.
C.Other Structural Elements:
1.Use Class AA(AE), unless shown otherwise. Refer to Section
03055.
2.Use Structural Concrete – Lightweight where shown. Refer to
Section 03057.
a.Use the concrete class shown.
3.Self-Consolidating Concrete (SCC) may be used at the Contractor’s
option. Refer to Section 03056.
a.Use the concrete class shown.
4.Use Class AA(ES) only where shown. Refer to Section 03055.
2.2JOINT FILLER AND SEALANT
A.Preformed Joint Filler – Refer to Section 03152.
B.Silicone Joint Sealer – Refer to Section 03152.
C.Self Leveling Silicone Joint Sealer – Refer to Section 03152.
D.Joint Sealer (Structures) – Refer to Section 03152.
2.3BACKER ROD
A.Refer to Section 03152.
B.Size the diameter of the backer rod to a minimum of ¼ inch larger than the
groove in which it is placed.
2.4WATERSTOPS
A.Refer to Section 03152.
Structural Concrete
2.5RIGID PLASTIC FOAM
A.Preformed, extruded, cellular polystyrene thermal insulation material that
has a water absorption property of 0.3 or less. Refer to ASTM C 578.
2.6FORMS
A.Plywood, wood, metal, glass, or a combination of these materials.
B.Use mortar-tight concrete forms, true to the dimensions, lines, and grades
of the structure and of sufficient rigidity to prevent objectional distortion of the formed concrete surface caused by pressure of the concrete and other loads incidental to the construction operations.
C.Discontinue using a form or forming system that produces a concrete
surface with excessive undulations until modifications have been made.
1.Undulations are excessive if they exceed either ⅛ inch over 10 feet
or 1/270 of the center-to-center distance between studs, joints, forms, fasteners, or wales.
D.Countersink all bolt and rivet holes when using metal forms for exposed
surfaces so that a plane smooth surface of the desired contour is obtained.
E.Use lumber that is free of knotholes, loose knots, cracks, splits, warps, or
other defects that affect the strength or appearance of the structure.
1.Rough lumber may be used for forming surfaces if visible rough
surfaces do not show on the final structure.
F.Form exposed element surfaces of a concrete structure with the same
forming material or with materials that produce a concrete surface that is uniform in texture, color, and appearance.
G.Do not use stay-in-place metal deck forms unless otherwise specified.
2.7MISCELLANEOUS STEEL ITEMS
A.Galvanize all miscellaneous steel items permanently cast into structural
concrete elements. Refer to AASHTO M 111.
2.8WATERPROOFING MEMBRANE
A.Refer to Section 07105.
Structural Concrete
2.9EQUIPMENT
A.Finishing Machine for Bridge Deck
1.Use a bridge deck finishing machine with automated systems to
spread and finish concrete for the full width of the bridge deck.
2.Provide a truss mounted paving carriage that includes but is not
limited to augers, rollers, and pans.
B.Finishing Machine for Approach Slabs
1.Use a finishing machine with motorized systems to spread and
finish concrete for the full width or length of the approach slab for slabs 25 feet or shorter.
2.Use Finishing Machine for Bridge Deck for approach slabs longer
than 25 feet.
2.10BARRIER DELINEATION
A.Sheeting. Refer to Section 02842.
B.Hardware. Refer to GW Series Standard Drawings.
PART 3 EXECUTION
3.1PREPARATION
A.Falsework
1.Design and construct falsework according to the AASHTO LRFD
Bridge Construction Specifications, Section 3 (Temporary Works).
a.Design falsework so that loads imposed on existing, new, or
partially completed portions of structures due to construction operations do not exceed the load carrying capacity of the structure or portion of the structure.
b.Brace and tie girders to resist forces that would cause
rotation or torsion in the girders from the placing of concrete for diaphragms or decks, or show girders to be adequate for those effects.
c.Do not weld falsework support brackets or braces to
structural steel members or to reinforcing steel.
2.Footing Construction
a.Build falsework on a solid footing that is safe against
undermining, protected from softening, and capable of supporting imposed loads.
Structural Concrete
b.Demonstrate that the soil bearing values do not exceed the
supporting capacity of the soil. 1) Conduct load tests or have soils investigation conducted by a professional engineer licensed in the State of Utah.
c.Use piling or drilled shafts to support falsework that cannot
be founded on a solid footing.
d.Space, drive, and remove piles according to the authorized
falsework drawings.
3.Construction
a.Use materialsable to sustain the stresses required by the
falsework design.
b.Use suitable jacks or wedges to set the forms to the grade or
camber required, and to prevent settling.
c.Produce a finished structure of the specified camber and
built to the lines and grades indicated.
B.Forms
1.Clean the inside surfaces of dirt, mortar, and foreign material before
concrete placement.
2.Use form oil that permits the ready release of the forms and does
not discolor the concrete.
3.Do not place concrete in the forms until:
a.All work connected with form construction has been
completed.
b.All embedded materials have been placed.
c.All dirt, chips, sawdust, water, and other foreign materials
have been removed.
d.Inspection and approval have been obtained.
4.Do not use stay-in-place deck forms unless otherwise specified.
C.Footings, Box Culverts, and Headwalls
1.Excavation and Backfill – Refer to Section 02317.
2.The Engineer may direct written changes in dimensions or
elevations necessary to secure a satisfactory foundation.
3.Do not dewater by pumping during concrete placement or for 24
hours thereafter unless pumping is outside the enclosure.
4.Do not use well points to dewater footing.
D.Bridge Decks
1.Reinforcing Steel
a.Pass the screed over the area with a screed face device to
measure the cover before concrete placement.
b.Relocate and tie reinforcing steel that projects above the
specified level before placing the concrete.
Structural Concrete
2.Screeds
a.Firmly support screed rails for bridge deck slabs to prevent
movement during concrete placement.
b.Support the machine rails on the bridge beams when using a
finishing machine.
c.Do not place the machine rails on the forms without an
authorized working drawing for deck overhang bracing.
d.Extend finishing machine rails beyond both ends of the
scheduled placement and allow sufficient distance to permit the float to fully clear the concrete.
e.Use adjustable rails set to provide the finished grade
elevations shown, installed to prevent springing or deflection under the weight of the finishing equipment, and placed to operate without interruption over the entire surface being finished.
f.Support screed rails to prevent movement during placing of
the concrete.
3.Hold a pre-activity meeting before placing cast-in-place concrete in
bridge decks and approach slabs.
a.Contractor, Department, and supplier personnel involved
with completing the work must attend the pre-activity meeting.
b.Conduct pre-activity meeting no more than seven calendar
days before the first scheduled concrete placement.
c.Provide notification of the meeting to the Engineer at least
seven calendar days in advance.
d.Discuss at least the following items specific to the concrete
work for each bridge deck and approach slab: 1) Material requirements 2) Schedule, quality control procedures, and verification testing. 3) Authorized Concrete Placing and Finishing Plan 4) Placement sequence and limits (including pouring sequence, direction of pour) 5) Construction details (for example, bridge skew angle, superelevation, and transitions) 6) Locations of finishing machine rail supports and construction joints (for example, grade control) 7) Concrete conveyance, placement equipment and methods, and rates (including haul distance, haul time, and placement) 8) Special equipment 9) Finishing methods 10) Curing plan (equipment and application rates) 11) Method of verifying placement and clearances of reinforcing steel Structural Concrete
12) Contingency plans include but are not limited to the following issues during construction:
a.Finishing machine break down
b.Concrete delivery delay
c.Concrete not meeting specification
requirements
d.Weather protection requirements
e.Additional meetings may be required as determined by the
Engineer.
E.Miscellaneous Construction
1.Drainage and Weep Holes
a.Construct drainage and weep holes at locations shown or as
directed.
b.Place ports or vents for equalizing hydrostatic pressure
below low water.
c.Use non-corrosive materials for weep hole forms.
d.Paint exposed surfaces of metal drains as shown.
2.Anchor Bolts
a.Securely and accurately set anchor bolts before concrete
placement.
b.Use templates to maintain location and plumbness.
3.Saturated Surface Dry (SSD)
a.Provide SSD condition to hardened concrete before placing
fresh concrete.
3.2PLACE CONCRETE
A.Do not place concrete without authorization from the Engineer.
B.Do not deviate from the Concrete Placing and Finishing Plan without
written authorization from the Engineer.
C.The Engineer may postpone placement operations if the concrete cannot
be protected during adverse weather.
D.Handling concrete:
1.Avoid segregation of the ingredients.
2.Arrange chutes, troughs, or pipes used as aids in placing concrete
so the concrete does not separate.
3.Use metal or metal-lined chutes and troughs. Do not use
aluminum.
4.Equip chutes with baffle boards or a reversed section at the end of
the outlet when placing on steep slopes.
5.Extend open troughs and chutes down inside the forms or through
holes left in the forms. Terminate the ends in vertical downspouts. Structural Concrete
6.Thoroughly flush all chutes, troughs, and pipes with water before
and after each placement.
7.Do not allow the free fall of concrete to exceed 10 ft for thin walls
(maximum 10 inch thickness) or 5 ft for other types of construction without the use of a tremie or a flexible metal spout.
8.Use flexible metal spout sections composed of conical sections not
more than 3 ft long, with the diameter of the outlet and the taper of the various sections so the concrete fills the outlet and retards concrete flow.
E.Placing concrete:
1.Deposit concrete as close as possible to its final position without
allowing it to flow laterally in the form.
2.Spread fresh concrete in horizontal layers with thickness not
greater than what can be compacted with vibrators.
3.Do not use vibrators to flow concrete laterally.
4.Limit placement interruptions to 45 minutes.
5.Place and vibrate each layer before the preceding layer has taken
initial set.
6.Do not place concrete in flowing water.
F.Consolidating concrete:
1.Use high frequency internal vibrators to consolidate all concrete for
structures except concrete placed under water.
2.Use enough vibrators to consolidate the fresh concrete to the
desired degree within 15 minutes after it is deposited in the forms.
3.Supply at least two vibrators for structures involving more than
25 yd3 of concrete.
4.Do not attach vibrators to or against the forms or the reinforcing
steel.
5.Do not allow vibrators to penetrate layers of concrete that have
taken initial set.
6.Use spades or wedge-shaped tampers to secure a smooth and
even texture of the exposed surface.
3.3PLACE CONCRETE UNDER WATER
A.Place and deposit concrete under water as shown.
B.Seal the forms or cofferdams watertight.
C.Do not pump water while placing concrete or disturb the concrete until it
has set at least 24 hours or attained at least 50 percent of the specified 28 day minimum compressive strength based on field cured cylinders.
D.Regulate placing to keep surfaces approximately horizontal at all times.
Structural Concrete
E.Place the concrete by beginning at one end of the form and progressing in
a zig-zag movement from side to side across the length of the form.
F.Place the concrete using a tremie or concrete pumping equipment.
G.Placing concrete with a tremie:
1.Use an 8 inch to 12 inch diameter steel tube tremie constructed
with watertight connections, a hopper to receive concrete, and a device at the bottom to exclude water from entering the tube.
2.Use support that permits the discharge end to move over the entire
top work surface and permits the tremie to be rapidly lowered to stop or retard flow when necessary.
3.Minimize the number of tremie location shifts for continuous
placement.
4.Keep the tremie tube full to the bottom of the hopper during
placement.
5.Slightly raise the tremie when a batch is dumped into the hopper
but do not raise it out of the concrete at the bottom until the batch discharges to the bottom of the hopper.
a.Re-plug the end and refill the tube with concrete if the
concrete seal around the tube is lost.
3.4PUMP CONCRETE
A.Use a prequalified concrete pumping contractor. Refer to UDOT Quality
Management Plan 511 – Concrete Pumping.
1.Replace pump that causes excessive or erratic loss of air
entrainment.
2.Use a pump that produces a continuous stream of concrete without
air pockets.
3.Do not add water to the concrete in the pump hopper.
B.Do not allow pump vibrations to damage freshly placed concrete.
C.Do not use concrete contaminated by priming or cleaning the pump.
3.5LIMITATIONS
A.Light the work site so all operations are plainly visible if mixing, placing, or
finishing occurs after daylight hours.
Structural Concrete
B.Keep traffic off concrete bridges, culverts, approach slabs and closure
pours until concrete satisfies curing requirements according to Section 03390 and achieves 100 percent of the specified 28 day minimum compressive strength based on field cured cylinders.
1.High-early strength concrete used in bridge deck and approach
slab closure pours may be opened to traffic 3 days after final concrete placement and after concrete achieves 100 percent of the specified 28 day minimum compressive strength based on field cured cylinders.
3.6CONSTRUCTION JOINTS
A.Make construction joints where shown.
B.Obtain Engineer’s authorization when additional construction joints are
desired and meet the following requirements:
1.Place and construct without impairing strength and appearance.
2.Place in planes perpendicular to the principal lines of stress and at
points of minimum shear.
3.Make monolithic structures by extending the reinforcing across the
joint.
4.Avoid construction joints through large surfaces that are to be
treated architecturally.
5.Make a straight line joint across the face of the concrete placement
for the full width of the element.
6.Leave or provide a rough surface of at least ICRI Concrete Surface
Profile (CSP) 5 to increase the bond with the concrete placed later.
a.Refer to http://www.udot.utah.gov/go/standardsreferences
for a CSP Examples document.
7.Form tapered sections with an insert so that the succeeding layer of
concrete ends in a section at least 6 inches thick.
8.Place a bulkhead from the surface to the top mat of steel to
establish a straight vertical face.
a.Shape the concrete below the top steel to a near vertical
face in line with the bulkhead.
b.Establish a straight vertical face by saw cutting to a minimum
depth of 1 inch when a bulkhead cannot be placed. 1) Shape the concrete below the saw cut to a near vertical face in line with the saw cut.
C.Meet the following before resuming concrete placement:
1.Re-tighten forms.
2.Verify or provide a rough surface of at least surface profile CSP 5.
a.Roughen the surface of hardened concrete without leaving
loosened particles or damaged concrete.
b.Repair reinforcing steel epoxy coating that is damaged.
Structural Concrete
3.Clean off concrete surface of foreign matter and laitance by
sandblasting.
4.Provide SSD condition.
3.7CONCRETE SURFACE FINISHING CLASSIFICATIONS
A.Ordinary Surface Finish – A true and uniform finished surface.
B.Rubbed Finish – A surface smooth in texture and uniform in appearance
free of form marks and irregularities.
C.Wire Brush or Scrubbed Finish
1.A finished surface with the cement surface film completely removed
and the aggregate particles exposed leaving an even-pebbled texture.
2.An appearance ranging from fine granite to coarse conglomerate
depends on the size and grading of the aggregate used.
D.Floated Surface Finish
1.Flat work – Strike off and use a floated surface finish.
2.Bridge decks and approach slabs – use a finishing machine unless
otherwise permitted.
3.8CONCRETE SURFACE FINISHING
A.Give all formed concrete surfaces at least an ordinary surface finish
except as specified otherwise.
B.Use other types of finishes as required in addition to the ordinary surface
finish.
C.Provide a rubbed finish for repaired surfaces that cannot meet ordinary
surface finish requirements due to irregularities, honeycombing, excessive surface voids, discoloration, and other defects.
3.9CONCRETE SURFACE FINISHING PROCEDURES
A.Ordinary Surface Finish
1.Remove all fins and projections after removing forms.
a.Clean, point, and true all honeycomb spots, broken corners
or edges, cavities made by form ties, and other holes and defects.
b.Keep all areas to receive mortar saturated with water for at
least 30 minutes before mortar placement.
Structural Concrete
2.Use a mortar made of cement and fine aggregate for pointing, not
more than one hour old, mixed in the proportions used in the grade of concrete being finished.
3.Cure the mortar patches and rub to blend with surrounding
concrete.
4.Tool and free all joints of mortar and concrete.
a.Leave the full length of the joint filler exposed with clean and
true edges.
B.Rubbed Finish
1.Wet the concrete surface as soon after form removal as conditions
permit, paint with grout, and rub with a wooden float until the surface is covered with a lather of cement and water.
a.A thin grout of one part cement, one part fine sand may be
used in the rubbing.
b.Let this lather set for at least three days then rub lightly with
a fine carborundum stone until smooth.
2.Use a mechanically operated carborundum stone to finish the
surface of hardened concrete at least four days after placing.
a.Finish in the same manner as ordinary surface finish.
1) Let the lather set for at least 7 days before lightly rubbing with a fine carborundum stone until smooth.
3.Commercial grade rubbing mortar may be used if authorized by
Engineer.
C.Wire Brush or Scrubbed Finish
1.Scrub the surface with stiff wire or fiber brushes using a solution of
muriatic acid – one part acid, four parts water as soon as forms are removed and while the concrete is relatively green.
2.Wash the entire surface once the scrubbing produces the desired
texture.
a.Use water mixed with 5 percent by volume ammonium
hydroxide to remove all traces of the acid.
D.Floated surface finish on flat work other than bridge decks and approach
slabs:
1.Striking Off
a.Carefully rod and strike off the surface with a strike board
following the cross sections and grades shown after compaction.
b.Allow for camber as required.
c.Operate the strike board longitudinally or transversely and
move it forward with a combined longitudinal and transverse motion so that neither end is raised from the side forms during the process.
Structural Concrete
d.Keep a slight excess of concrete in front of the cutting edge
at all times.
2.Floating
a.Use longitudinal or transverse floating or both to create a
uniform surface.
b.Longitudinal floating is required except in places where it is
not feasible.
3.Longitudinal Floating
a.Work the longitudinal float operated from foot bridges with a
sawing motion while holding it parallel to the road centerline.
b.Pass gradually from one side of the pavement to the other.
1) Move the float forward ½ of its length and repeat operation.
c.Substitute machine floating if equivalent results are
produced.
4.Transverse Floating
a.Operate the transverse float across the concrete surface by
starting at the edge and slowly moving to the center and back again to the edge. 1) Move the float forward ½ of its length and repeat the operation.
b.Preserve the crown and cross section of the concrete
surface.
5.Straightedging
a.Test the concrete surface for trueness with a straightedge
after the longitudinal floating has been completed and the excess water has been removed while the concrete is still plastic.
b.Furnish and use an accurate 10 ft straightedge held parallel
to the road centerline in contact with the surface.
c.Check the entire area immediately filling depressions with
freshly mixed concrete, then strike off, consolidate, and refinish.
d.Cut down and refinish high areas.
e.Continue the straightedge testing and re-floating until the
concrete surface is at the required grade and contour.
E.Floated Surface Finish for Bridge Decks and Approach Slabs
1.Use a finishing machine on exposed surfaces unless otherwise
permitted.
2.Finish concrete by striking off and floating the surface.
3.Allow the Engineer enough time to inspect finishing machines
during daylight hours before concrete placement.
4.Provide lighting facilities that adequately light the work area when
placing and finishing operations are not completed during daylight hours. Structural Concrete
5.Place finishing machine parallel to the abutments and bents within
10 degrees.
6.Attach a measuring device to the screed face and pass it over the
area.
7.Place concrete in a uniform heading approximately parallel to the
finishing machine.
8.Limit the rate of placing to allow enough time to finish the surface
before initial set.
9.Continuously place concrete the full length of the structure or
superstructure unit unless otherwise shown or authorized.
10.Provide sufficient material, equipment, and manpower to place
deck concrete at a rate of at least 25 yd3/hour.
11.Strike off the surface to the required elevations with the finishing
machine immediately after placing and consolidating the concrete.
12.Do not add water to the concrete in front of or behind the screed.
13.Obtain authorization for the strike-off method and equipment.
a.Maintain satisfactory performance.
b.Use equipment capable of finishing concrete within the
surface tolerances specified. 1) Provide a deck and approach slab thickness that is within -1/8 inches and +1/4 inches shown.
c.Maintain satisfactory consolidation and surface tolerance to
prevent shutdown and rejection of the equipment.
14.Drive finishing machine beyond the scheduled placement and allow
sufficient distance to permit the float to fully clear the concrete.
15.Furnish a 10 ft straightedge to check the surface tolerance, placed
both longitudinally and transversely, immediately behind the finishing machine and in hand-finished areas.
16.Correct irregularities greater than ⅛ inch from the straightedge,
before additional placement, and immediately fill depressions with concrete and refinish.
17.Cut down and refinish high areas.
18.Continue straightedge testing and corrective measures until the
entire surface is free of observable departures from the straightedge.
F.Final texturing for bridge decks and approach slabs – a textured hardened
finish:
1.Use a texture process that produces regular ⅛ inch wide transverse
grooves spaced randomly from ½ inch to ¾ inch on centers and ⅛ inch deep.
2.Keep the finished surface free from porous spots and surface
irregularities.
3.Furnish a work bridge that follows the finishing machine to facilitate
texturing and application of the curing compound.
Structural Concrete
4.Check the surface smoothness for acceptance after the concrete
has hardened. Refer to Section 02701.
3.10JOINT FILLER AND SEALANT
A.Provide joint filler or sealant as shown.
3.11CONCRETE CURING
A.Refer to Section 03390.
3.12FORM REMOVAL
A.Obtain authorization from the Engineer before removing forms.
B.Remove struts, stays, and braces that hold the forms in correct shape and
alignment when no longer necessary.
C.Remove all forms from the concrete surfaces.
1.Do not use a method of form removal likely to cause overstressing
of the concrete.
D.Remove supports to permit the concrete to uniformly and gradually take
the stresses due to its own weight.
E.Do not remove forms used in ornamental work, railings, parapets, and
exposed vertical surfaces for at least twelve hours after placement.
F.Always remove forms before removing shoring from beneath beams and
girders to determine the condition of columns.
G.Removing Falsework
1.Do not remove falsework supporting the deck of rigid frame
structures until the fill has been placed in back of the vertical legs.
2.Keep falsework and forms in place under slabs, beams, and girders
for 14 days after the day of last concrete placement.
a.Slab forms with a clear space of less than 10 ft may be
removed after seven days.
3.Keep forms and falsework in place in cold weather according to the
authorized Cold Weather Concreting Plan. Refer to Section 03055.
H.Patch formed surfaces within 24 hours after form removal.
1.Cut back and remove all projecting wire or metal devices used for
holding the forms in place and that pass through the body of the concrete at least 1 inch beneath the surface of the concrete.
2.Remove lips of mortar and irregularities caused by form joints.
Structural Concrete
3.Fill small holes, depressions, and voids with cement mortar mixed
in the same proportions as that used in the body of the work.
4.Obtain a solid uniform surface by chipping away coarse or broken
material to patch larger holes or honeycombs.
a.Cut away feathered edges to form faces perpendicular to the
surface.
b.Fill the cavity with stiff mortar composed of one part portland
cement to two parts sand thoroughly tamped into place.
c.Pre-shrink the mortar by mixing it approximately 20 minutes.
1) Vary the time according to manufacturer’s recommendations, temperature, humidity, and other local conditions.
d.Float the surface of this mortar with a wooden float before
initial set.
e.Keep the patch wet for five days.
f.Rub patches on exposed surfaces to blend them with
surrounding concrete after curing.
g.Add coarse aggregate to the patching material when
patching large or deep areas.
h.Make a dense, well-bonded, and properly cured patch.
I.Areas with extensive honeycombing will be rejected.
J.Apply the following requirements after fully removing all the closure joint
forms if inserts are placed along the bottom edges of the precast concrete deck panels to form the closure pour joints:
1.Cut off cast-in-place anchors at least 1 inch below the face of slab
and repair according to this Section, Article 3.12, paragraph H.
2.Fill all voids with dry-pack mortar flush with the bottom of slab.
3.Fill voids created by the removal of re-usable concrete anchors with
dry-pack mortar flush with the bottom of slab.
4.Dry-pack mortar will be composed of one part portland cement to
two parts sand.
3.13SUPERSTRUCTURE
A.Bridge decks and approach slabs
1.Follow the authorized Concrete Placing and Finishing Plan when
placing cast-in-place concrete.
Structural Concrete
2.Do not place parapet forms or parapet for at least seven days after
deck placement and until the deck has attained the specified 28 day minimum compressive strength based on field cured cylinders, unless falsework is left in place and is designed to carry the additional loads that are part of the parapet placement process.
a.Do not allow the installation of the parapet and parapet
forms to interrupt the curing of the deck and approach slabs when installed before curing is complete.
B.Partial-depth precast concrete deck panels
1.Provide SSD condition prior to placement of cast-in-place concrete.
C.Slab Span
1.Place concrete in one continuous operation.
D.Cast-In-Place T-Beams
1.Place concrete in one or two continuous operations – first to the top
of the girder stems and second to completion, unless otherwise shown.
2.Obtain a bond between the stem and slab that is positive and
mechanical and secured by means of shear keys or roughened surface in the top of the girder stem.
E.Do not place the approach slab until the sleeper slab concrete has been in
place at least seven days or has attained 70 percent of the specified 28 day compressive strength based on field cured cylinders.
3.14SUBSTRUCTURE
A.Concrete in Columns and Bent Stems
1.Allow footing concrete to set until it has attained 70 percent of the
specified 28 day minimum compressive strength based on field cured cylinders before placing column forms when column is being placed on a footing.
2.Place concrete in one continuous operation.
3.Allow concrete to set at least two days and until it has attained 70
percent of the specified 28 day minimum compressive strength based on field cured cylinders before placing caps.
B.Substructure Concrete
1.Do not place the superstructure load on the bents or abutments
until they have been in place at least seven days and attained 70 percent of the specified 28 day minimum compressive strength based on field cured cylinders.
Structural Concrete
C.Do not backfill abutments, wingwalls, and retaining walls until all concrete
has been in place at least 7 days and has attained 100 percent of the specified 28 day minimum compressive strength based on field cured cylinders.
1.Do not interfere with curing.
3.15BOX CULVERTS
A.Allow base slab and footing to attain 70 percent of the specified 28 day
minimum compressive strength based upon field cured cylinders before constructing the remainder of the culvert.
B.Construct side walls and top slab monolithically unless the wall height
exceeds 10 ft.
1.Keep the construction joints vertical and at right angles to the axis
of the culvert.
C.Construct shear keys in the top of the side walls for anchoring the top slab
when side walls and top slab are not placed monolithically.
D.Construct wingwalls monolithically.
E.Apply waterproofing membrane to the top slab and side walls once the
concrete satisfies curing requirements according to Section 03390.
1.Apply along the full length of the structure.
F.Do not backfill until the concrete has attained 100 percent of the specified
28 day minimum compressive strength based on field cured cylinders.
3.16HEADWALLS
A.Allow apron and pipe collar to attain 70 percent of the specified 28 day
minimum compressive strength based on field cured cylinders before the remainder of the headwall is constructed.
B.Construct wingwalls monolithically.
C.Do not backfill headwalls and wingwalls until all concrete has attained 70
percent of the specified 28 day minimum compressive strength based on field cured cylinders.
3.17CONCRETE SLOPE PROTECTION
A.Preparing Subgrade
1.Prepare the area to be paved by smoothing and shaping the berms
and slopes and excavating for the cut-off walls. Structural Concrete
2.Fill and compact subgrade – Refer to Section 02056.
a.Furnish extra material to properly finish the slopes when
required.
b.Compact all soft and yielding material resulting in a firm and
substantial subgrade of uniform density.
3.Thoroughly spray the area with water before placing the concrete.
B.Placing Concrete
1.Do not place concrete upon spongy, frozen, or unstable surfaces.
2.Provide concrete of a consistency that it can be placed on the
slopes without deformation.
3.Complete all horizontal grooves and vertical joints as shown.
4.Complete the entire slope protection in one placement if possible or
terminate the placement with a construction joint located in the horizontal grooves or vertical joints.
5.Finish concrete using a Floated Surface Finish according to this
Section, Article 3.9.
C.Seal Joints and Closures – Refer to 07921.
3.18RETAINING WALLS
A.Allow footing concrete to set until it has attained 70 percent of its specified
28 day minimum compressive strength based on field cured cylinders before placing wall forms.
B.Do not backfill walls until all concrete has attained 100 percent of the
specified 28 day minimum compressive strength based on field cured cylinders.
3.19MISCELLANEOUS CONSTRUCTION
A.Bearing Areas
1.Finish bridge seat bearing areas high and rub or grind to elevation
shown.
a.Level to within an allowable tolerance of ±1/16 inch and within
a tolerance of ± ⅛ inch of the elevation shown.
2.Do not grout under bearing plates.
3.20CLEANUP
A.Remove falsework and falsework piling to 2 ft below the finished ground
line, rubbish, and temporary building materials before final inspection.
Structural Concrete
3.21DELINEATION HARDWARE
A.Attach to parapet as shown.
END OF SECTION
Structural Concrete
Structural Concrete in other states
Utah revises spec sections through supplementals and new editions. We check this one every week and email you the day it changes. Free, no account.
Source: Utah Standard Specifications for Road and Bridge Construction, 2026 Edition. Pages 969–989 of 1,331.
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