FLOOD09874

• County: Statewide
• Community: State of Colorado
• Basin: Statewide
• Title: Use of Riprap for Bank Protection
• Date: 6/1/1967
• Prepared By: USDOT
• Floodplain - Doc Type: Project

Appendix B - SAMPLE RIPRAP SPECIFICATIOBS

.

Purpose

-::

The SAMPLE specifications are intended as a guide 0Dly". For use
in a particular State, the test values in section 10-2.1 should be modi-
fied by the experience of the State regardiug.the weatheriug at local
rock. Sections on various types of riprap which are not applicable in a
particular State my be deleted or specifications for other types ot rip-
rap might be added. The Clllission of specificatiCllls tor hand-placed stcllle
riprap will be noted. The poor pertormance and high cost ot hand-placed
riprap as contrasted with dumped riprap make its use in highway construe-
tion undesirable except in a tew instances when it is used tor improving
the esthetic quality ot the protection.

The three classes of riprap described in sectiCIII 10-2.1 are intended
to provide a light, me4ium, and heavy class of riprap of satistactory
gradation. The three classes shown in these SAMPLE specifications lllight
not provide a suitable range of riprap size tor conditions in some States.
Individual specifications might require heavier or lighter classes or theY"
might provide the tolloving single gradation reterenced to the 50 percent
size (k).

Size of Percent at total weight
stone smaller than the given size
. 3k 100
2k 80
lk 50
O.lk 10

Classes at concrete in these guide specitications are defined in
AASHO "Standard Specitications for Highway Bridges" and in most State
specifications. aeterences to sectiCllls at specifications can be tound
in the AASHO bridge specifications but would IIOre properly be covered by
the State specifications of which the riprap specitications would become
a part.

.

The principal sources of material tor these SAMPLE speciticatioDS
are various Corps ot Engineers publicatiou and specifications; the report
of the ASCE SubcOlllDittee on Slope Protection ot the COIIIDIittee on Earth
Dams of the Soil Mechanics and Foundations Division, June 1948 Proceedings;
the California DivisioD of Highways publication, "Bank and Shore ProteCtiCIII
in California Highway Practice"; and the U.S. Bureau at Reclamation's pub-
lication, "Design ot Small Dams."

.

11-35