Part 1 — General
1.1 Section Includes
A.Loose and compacted riprap.
1.2 Related Sections
A.Section 02075: Geotextiles
B.Section 02317: Structural Excavation
1.3 References
A.AASHTO T 85: Specific Gravity and Absorption of Coarse Aggregate
B.AASHTO T 96: Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine
C.AASHTO T 104: Soundness of Aggregate by Use of Sodium Sulfate or Magnesium Sulfate
1.4 Definitions
A.D50 - The median rock diameter within a riprap mass for which 50 percent of the rocks are smaller and 50 percent are larger.
B.Rock diameter - The equivalent diameter (average width) of a given rock.
1.5 Submittals
A.The rock source, gradation, and laboratory values for the properties in Table 1, for information.
Part 2 — Products
2.1 Riprap
A.Rock
1.Angular, hard, durable, resistant to weathering and free from seams, cracks and other structural defects.
a.Do not use shale, mudstone, or other rock that may break into smaller pieces in the process of handling and placing.
b.Do not use concrete or asphalt rubble.
2.Meet the properties listed in Table 1. Table 1 Physical Properties Property Value Test Method Specific Gravity 2.5 min AASHTO T 85 Absorption 2% max AASHTO T 85 Soundness of Aggregate using Sodium Sulfate 12% max AASHTO T 104 or or Magnesium Sulfate 17.5% max Resistance to Degradation 40% max AASHTO T 96
3.Well graded rock throughout the riprap layer to produce a dense mass. Refer to Table 2 for riprap gradation limits.
a.Control gradation by sample measurement or by visual inspection, as determined by the Engineer. Table 2 Riprap Gradation Limits Rock Diameter Range Percent of Gradation (ft) Smaller Than 1.5D50 to 1.7D50 100 1.2D50 to 1.4D50 85 1.0D50 to 1.15D50 50 0.4D50 to 0.6D50 15 0.1D50 10
2.2 Erosion Control Geotextile
A.Refer to Section 02075, except use a nonwoven 12 oz/yd2 minimum average roll value.
Part 3 — Execution
3.1 Preparation
A.Excavate and grade to provide a firm and uniform bearing surface. Refer to Section 02317.
B.Install erosion control geotextile as shown.
3.2 Loose Riprap
A.Place rocks to provide a secure unsegregated dense mass.
1.Distribute and manipulate the rocks so that the larger rocks are uniformly distributed and the smaller rocks serve to fill the spaces between the larger rocks.
3.3 Compacted Riprap
A.Place rocks conforming to this Section, Article 3.2.
B.Compact riprap to remove irregular surface protrusions larger than 3 inches.
Riprap in other states
Get an email when 02373 changes
Utah revises spec sections through supplementals and new editions. We check this one every week and email you the day it changes. Free, no account.
Source: Utah Standard Specifications for Road and Bridge Construction, 2027 Edition. Pages 320–322 of 1,343. View official source ↗