SLOPE PROTECTION
613.01 Description
This work is the construction of protective rock, stones, gravel, or concrete coverings as specified. Riprap is rock protection and is a cover of stone or fragmented rock, with or without grout, placed along embankment slopes, stream banks, culvert inlets and outlets, foundations, bridge berms, dikes, and other specified locations. Ancillary Armor is rock protection used in low-risk applications such as culvert outlet protection or lined ditches. Concrete slope protection is a cover of hydraulic cement concrete placed on slopes at structure ends.
613.02 Materials
Furnish materials in accordance with the following section and subsection requirements: Ancillary Armor ........................................................ 701.06 Bedding Material ..................................................... 701.04.1 Hydraulic Cement Concrete .................................... 551 Random and Grouted Riprap .................................. 701.06 Sand-gravel Cushion ............................................... 701.08
613.03 Construction Requirements
613.03.1 Riprap and Ancillary Armor
A.General. Place the rock protection at the locations specified in the contract. Key the rock protection into the embankment slopes at least 2 feet (610 mm) from the outer face for the full height of the rock protection.
B.Random Riprap. Place the stones on the slopes to form the specified cross section. Uniformly distribute the smaller stones throughout the work. Manipulate the stones by hand or machine to provide a uniform surface and stable mass. Provide the riprap thickness specified in the contract. Place the riprap around pipe openings without damaging the pipe. Repair damaged pipe at Contractor expense.
C.Grouted Riprap. Provide a minimum riprap thickness of 9 inches (230 mm) measured perpendicular to the slope, or as specified. Place one or more layers of bedding material before placing the riprap as specified. Place each bedding layer on the prepared surface to the specified thickness in one operation without segregating the layer. Finish the top layer to produce an even surface free from mounds or ridges. Do not inter-mix the materials of each layer. Fill the voids between stones with spalls or small stones so all stones are wedged or keyed. Prevent earth and sand from filling the spaces between the stones. Finish the final surface to provide an even, tight surface with the plane not varying more than 3 inches (75 mm) from the general contour. Wet the riprap surface and fill the crevices and openings with at least 3 inches (75 mm) of mortar. Immediately sweep the surface with a stiff broom. 613 – RIPRAP AND SLOPE PROTECTION 2020 EDITION V5.1 613-2 Grouting may begin when the ambient temperature is at least 35 °F (2 °C) and rising and must stop when the ambient temperature is 30 °F (−1 °C) and falling. Keep finished grout work moist for 3 days.
D.Acceptance. Ensure riprap and ancillary armor placement is uniformly distributed. Gradation acceptance is determined by visual analysis and use of optical granulometry software and will be verified in the final placement location. Prior to final placement the Contractor may request a maximum of 3 courtesy tests of the riprap and ancillary armor gradation. Once in place, and prior to covering or revegetating the riprap and ancillary armor, notify the Project Manager for in-place gradation testing.
613.03.2 Concrete Slope Protection
Trench, shape, compact, and trim the slopes as specified before starting concrete work. Excess excavated material may be used elsewhere in the work or disposed of by the Contractor. Construct the concrete slope protection as specified or directed.
613.04 Method of Measurement
613.04.1 Riprap and Ancillary Armor
A.Random Riprap. Random riprap is measured by the cubic yard (m
3.complete in place. The volume measured for payment is that bounded by the staked length and height and the plan thickness. Excavation is incidental to the riprap and not measured for payment.
B.Grouted Riprap. Grouted riprap is measured by the square yard (m
2.on the face of the revetment. Excavation is incidental to the riprap and not measured for payment. Bedding material is measured by the cubic yard (m3).
C.Ancillary Armor. Bank protection is measured by the cubic yard (m3) complete in place. The volume measured for payment is that bounded by the staked length and height and the plan thickness. Excavation and bedding material are not measured for payment.
613.04.2 Concrete Slope Protection
Concrete slope protection is measured by the square yard (m 2). Measurement is made parallel to the surface of the exposed surface area including the surfaces of curbs and head walls. Excavation is incidental to the item and not measured for payment. Sand-gravel cushion is measured by the cubic yard (m
3.compacted in place.
613.05 Basis of Payment
Payment for the completed and accepted quantities is made under the following: Pay Item Pay Unit Ancillary Armor Cubic Yard (m3) Bedding Material Cubic Yard (m3) Concrete Slope Protection Square Yard (m2) Grouted Riprap Square Yard (m2) Random Riprap Cubic Yard (m3) Sand-gravel Cushion Cubic Yard (m3)
Referenced in this section
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Source: Standard Specifications for Road and Bridge Construction, 2020 (v5.1) Edition. Pages 449–450 of 611. View official source ↗