Section 2415. Concrete Box, Arch, and Circular Culverts
Construct a cast-in-place concrete box, arch, or circular culvert.
1. Apply Section 2419.
2. Use culvert sections that meet the requirements of ASTM C 1577 or Iowa DOT Single Precast RCB Culvert Standards.
contract documents will designate the culvert
span, rise, and
either the design
earth cover , or the design loading, both
defined in ASTM C 1577.
coarse aggregate in concrete mixture from an approved source meeting
requirements of Section 4115, with Class 2 or better durability rating.
5. Concrete strength will be based on cylinder tests.
6. Shop drawing submittal required as per the contract documents.
Use Class C structural concrete meeting the requirements of Section 2403, unless specified otherwise.
Apply Section 2419
A 1. Footings.
1 a. Construct
footings to the elevations shown in the contract documents, unless directed
otherwise by the Engineer.
2 b. Footing
depths may be increased when necessary to prevent undermining or scour or to
secure adequate bearing. In general, decrease footing depth only when solid
rock is encountered at elevations above those shown.
3 c. Use
suitable wood or metal forms according to Section 2403 to enclose all footing
B 2. Placing
1 a. Footings. a. 1)Do
not allow dirt, mud, or other foreign material to become mixed with concrete
which is being placed in the footing. b. 2)Monolithically
construct footings, pavements, and curtain walls between construction joints if
practical. c. 3)Provide
a key notch of the form shown in the contract documents between the walls and
footings to insure proper anchorage. d. 4)Remove
all dirt, dust, shavings, or other foreign material from the key notch and wall
forms before placing concrete.
2 b. Barrels of
Culverts. a. 1)The
sidewalls and top slab may be constructed as a monolith between construction
joints, or the concrete in sidewalls may be placed and allowed to harden before
the top slab is placed, at the discretion of the Contractor. b. 2)If
the sidewalls and top slab are constructed as a monolith, all necessary
construction joints are to be vertical and at right angles to the axis of the
culvert. If the sidewalls are placed and allowed to harden before the top slab
is placed, leave appropriate keys in the sidewalls for anchoring the cover
slab. c. 3)Place
forming and reinforcement for the entire barrel section between construction
joints before concrete is placed in the sidewalls or headwalls.
3. c. Headwalls.
general, construct headwalls monolithically. However, when construction joints
are unavoidable, place them in a horizontal or vertical position and locate
them so no joint is visible above the roadbed. b. 2)Place
triangular fillet strips in the forms to avoid sharp edges and corners.
Concrete in Arch Culverts.
Place concrete in arch culverts as provided in Section 2403.
C 3. Surface
Surface all exposed parts of the wingwalls, headwalls, and railings according to Article 2403.03, P.
D 4. Placing
Place backfill material according to Article 2402.03, H.
E 5. Protection
1 a. Furnish
and install protection railings shown in the contract documents.
2 b. Paint
protection railings, other than aluminum or galvanized railings, as provided in
1. Apply Section 2419.
2. Place backfill material according to Article 2402.03, H.
A. Payment for
cast-in-place concrete box, arch, or
circular culverts will be the contract unit price for excavation for
structures, structural concrete, steel reinforcement, and other items included
in the contract documents.
C. Payment for precast box culverts items will be as noted in the contract documents.
are full compensation for furnishing all materials, equipment, and labor and
for performance of all work necessary to complete the structures in conformance
with the contract documents or as ordered by the Engineer.