00390.00 302 Section 00390 - Riprap Protection
Description
00390.00Scope - This Work consists of furnishing and placing an erosion resistant cover M aterial
for protecting slopes and basins at locations shown or as directed.
00390.01Definitions :
Riprap Geotextile - A geotextile placed between the area prepared for it and the riprap.
Filter Blanket - A layer of graded Granular Material placed between the area prepared for it and the riprap.
Loose Riprap - Specified classes of graded Rock placed on prepared slope, Riprap Geotextile or Filter Blanket, as specified. Keyed Riprap - Loose Riprap placed on prepared slope, R iprap Geotextile or F ilter Blanket, as specified, and keyed in place by slapping the surface with a piece of armor plating. Grouted Riprap - Loose Riprap with all or part of the spaces filled with p ortland cement mortar. Riprap Basin - Energy dissipater consisting of Loose Riprap placed at pipe outlets as specified.
Materials
00390.10Riprap Geotextile - Furnish riprap Geotextile meeting the requirements of Section 02320
00390.11Riprap Requirements :
• Meet the test requirements of 00390.11(b). • Be angular in shape. Thickness of a single Rock shall not be less than one-third its length. Rounded Rock will not be accepted unless authorized by the Engineer. • Meet the gradation requirements for the class specified. • Be free from overburden, spoil, shale and organic material. Nondurable R ock, shale or Rock with shale seams is not acceptable.
Material Test Requirement
Apparent Speci fic Gravity (AASHTO T 85) 2.50 Minimum % Absorption (AASHTO T 85) 6.0 Maximum Degradation (ODOT TM 208) Passing No. 20 Sieve 35.0% Maximum Sediment Height 8.0" Maximum Soundness (AASHTO T 104) Average Loss of 2 1/2" - 1 1/2" and 1 1/2" - 3/4" fraction after 5 alternations 16.0% Maximum
following: 00390.41 303 Class Class Class Class Class 50 100 200 700 2000 Percent Weight of Rock (Pounds) (by Weight)
50 - 30 100 - 60 200 - 140 700 - 500 2000 - 1400 20.0 30 - 15 60 - 25 140 - 80 500 - 200 1400 - 700 30.0 15 - 2 25 - 2 80 - 8 200 - 20 700 - 40 40.0 2 - 0 2 - 0 8 - 0 20 - 0 40 - 0 10.0 - 0
Uniformly grade each load of riprap from the smallest to the l argest weight specified. Control of gradation will be by visual inspection.
sample of at least 5 T ons meeting the gradation for the class specified. This sam ple will be used as a frequent visual reference for judging the gradation of the riprap supplied.
the Contractor shall be resolved by dumping and checking the gradation of two random truckloads of Rock . Mechanical Equipment , a sorting site and labor needed to assist in checking gradation shall be provided by the Contractor at no additional cost to the Agency.
00390.12Grouted Riprap - Furnis h Rock for Grouted Riprap meeting the requirements of 00390.11,
and furnish the p ortland cement grout meeting the requirements of 02080.40.
00390.13Filter Blanket - Furnish Filter Blanket Materials meeting the following r equirements
according to riprap class: Riprap Class Filter Blanket
Class 2000 16 inch layer of Class 50 riprap conforming to 00390.11
Class 700 9 inch layer of 6" - 0 stone embankment meeting the test requirements of 00330.16
Class 200 6 inch layer of 4" - 0 stone embankment meeting the test requirements of 00330.16
Class 100 No Filter Blanket required
Class 50 No Filter Blanket required
Construction
00390.40Preparation - Remove brush, trees, stumps and other organic material from slopes to be
protected by riprap and dress to a smooth surface. Remove all Unsuitable Material to the depth shown or directed and replace with approved Material . Compact filled areas as speci fied in Section 00330.
Provide riprap protection as early as the Structure foundation construction permits. Prepare the surfaces to be protected as shown. Maintain the trench Slopes , Riprap Geotextile or Filter Blanket until the riprap is placed.
00390.41Riprap Geotextile - Install Riprap Geotextile according to Section 00350 and as shown or
directed. 00390.42 304
00390.42Filter Blanket Construction - Place the Filter Blanket on the prepared area to the full
specified thickness in one operation, using methods which do not cause segregation.
00390.44Riprap :
constructed. Its placement shall lag behind embankment construction only as necessary to allow proper embankment construction and prevent mixture of embankment and riprap M aterial .
• With a clam -shell, orange-peel bucket, skip or similar approved device which will contain the riprap Material to its final destination. Do not open the bucket until it has been lowered to the slope on w hich the M aterial is being placed. • To its full Course thickness in one operation. • According to 00350.41(d), if riprap is placed on geotextile. • By methods that do not cause segregation of riprap or displace the underlying material. • To produce a compact riprap protection in which all sizes of M aterial are placed in their proper proportion. • With some hand placing, or rearranging of individual stones by mechanical Equipment , or some other approved means to provide a smooth finished surf ace. Where filter M aterial or riprap are placed under water, increase their thicknesses as shown or as directed.
(b), key the riprap into place by slapping the surface with a piece of armor plating (approximately 4 feet x 5 feet in size weighing approximately 5,000 pounds) or other approved
means which will produce a nearly smoot h surface.
the depth specified for grouting is more than 12 inches, place the riprap in Lifts of 12 inches or less and grout each Lift before placing the next Lift. Construct and grout the succeeding Lifts before the grout in the previous Lift has hardened.
Thoroughly moisten the stones and sluice any excess fines to the underside of the riprap before grouting. Deliver the grout to the place of final deposit by any means that will ensure uniformity and prevent segregation of the grout. Spade or rod the grout into the spaces to completely fill the voids in the riprap. Control pressure grouting and do not unseat the stones. Penetration of the grout shall be t o the depth as shown. If a rough surface is specified, brush the stone until 25 to 50 percent of the depth of surface stone is exposed. For a smooth surface, grout the crevices to within 5/8 inch of the surface.
Provide weep holes through the riprap as shown or as directed.
Place and cure grout according to 00440.40(d) and 00440.40(e) except as provided above.
or Filter Blanket, at pipe outlets with Class 5 0 riprap as shown or as directed.
00390.90 305 Maintenance
00390.60General - Maintain the riprap protection until accepted. Replace any M aterial displaced by
any cause at no additional cost to the Agency.
Measurement
00390.80Measurement - The quantities of Work performed under this Section will be measured
according to the following:
to the Neat Lines shown or directed.
When measurement of riprap is on the volume basis in place and the Engineer determines that this basis is impractical, the pay volume will be determined by loose measure in the hauling vehicles on the basis that 1.00 cubic yard, vehicle measure, is equivalent to 0.70 cubic yard in place.
Payment
00390.90Payment - The accepted quantities of Work performed under this Section will be paid for
at the Contract unit price, per unit of measurement, for the following items:
Pay Item Unit of Measurement
In items ( b), (c), and ( d), the class of riprap will be inserted in the blank.
Item ( c) includes the grout.
Riprap Geotextile will be paid for according to 00350.90.
Payment will be payment in full for furnishing and placing all Materials, and for furnishing all Equipment , labor, and Incidentals necessary to complete the Work as specified.