FLOOD09724

• County: Statewide
• Basin: Statewide
• Title: Culvert Inspection Manual Supplement to the Bridge Inspectors Training Manual
• Date: 5/1/1986
• Prepared For: Federal Highway Administration
• Prepared By: Office of Engineering
• Floodplain - Doc Type: Educational/Technical/Reference Information

placed or moves too close to the walls, creating unbalanced loadings.
Additional protective fill may be needed for equipment crossing points.

e. Camber--In high fills the center of the embankment tends to settle more
than the areas under the embankment side slopes. In such cases it may be
necessary to camber the foundation slightly, as shown in exhibit 26. This
should be accomplished by using a flat grade on the upstream half of the
culvert and a steeper grade on the downstream half of the culvert. The
initial grades should not cause water to pond or pocket.

!

II ~ ~ f

Cambered Pipe

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--

--
--

-

camber

-~

Final grade after settlement

Source: Handbook for Steel Drainage and Highway Products
American Iron and Steel Institute

Exhibit 26. Camber allows for settlement of a culvert under a high fill.

. Section 4. DURABILITY

3-4.0 General.

Although the structural condition is a very important element in the
performance of culverts, durability problems are probably the most frequent
cause of replacement. Culverts are more likely to "wear away" than fail
structurally. Durability is affected by two mechanisms: corrosion and
abrasion. Each are discussed in the following sections:

a. Corrosion--Corrosion is the deterioration of culvert materials by
chemical or electrochemical reaction to the environment. Culvert corrosion
may occur in many different soils and waters. These soils and waters may
contain acids, alkalis, dissolved salts, organics, industrial wastes or other
chemicals, mine drainage, sanitary effluents, and dissolved or free gases.
However, culvert corrosion is generally related to water and the chemicals
that have reacted to, become dissolved in, or been transported by the water.

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