MnDOT Standard Specifications 3601: Riprap Material

3601.1SCOPE

Provide stone and filter Layer Material for use in random or hand-placed riprap, gabion, and revet mattress construction.

3601.2REQUIREMENTS

A Random Riprap A.1 Sizing Requirements Meet the requirements of Table 3601.2-1. Table 3601.2-1 Random Riprap Gradation Requirements Class Median Particle Diameter (inch) Minimum and Maximum Allowable Particle Size (inches) D15 D50 D85 D100 Min Max Min Max Min Max Min Max I 3 1 3 2 4 3 5 4 6 II 6 3 6 5 8 7 11 9 12 III 9 6 8 8 11 11 15 15 18 IV 12 8 10 10 14 15 19 21 24 V 15 9 12 12 17 19 23 27 30

A.2 Quality Requirements Provide stone of the quality approved by the Department and meeting the following requirements:

(1)Each individual stone has at least one fractured face. For the purpose of the

Work specified in section 3601, “Riprap Material” an acceptable fractured face is defined as a broken surface constituting an area equal to at least 50 percent of the projected area of the particle, as viewed perpendicular to (looking directly at) the fractured face.

(2)Is free of soil or other debris before placement

(3)Contains less than 10 percent of the following by weight:

(a)Stones with defects that could cause rapid or excessive deterioration

or degradation during service, such as cracks or seams

(b)Stones with a width or thickness less than 30 percent of the length

(4)For Carbonate quarry/bedrock Material used in total or in part for riprap, the

portion of the insoluble residue passing the No. 200 Sieve is no greater than 10 percent

(5)Use 100 percent virgin Materials for riprap and granular filter

To determine suitable quality of stone, the Department may consider the results of laboratory tests, the performance of the stone under natural exposure conditions, the performance of the riprap from the same or similar geological formations or deposits, or other tests or criteria.

B Hand-placed Riprap B.1 Sizing Requirements Provide individual stones with a weight of at least 50 pounds. The Department will not require a minimum weight for smaller stones required for filling in the narrow openings between individual stones (chinking). B.2 Quality Requirements Meet the requirements of 3601.2A.2, “Quality Requirements.” C Gabions and Revet Mattresses C.1 Sizing Requirements Provide well graded stones for filling the baskets, ranging in size from 4 inches to 8 inches for gabions and 3 inches to 6 inches for revet mattresses. C.2 Quality Requirements Provide stone that is free of soil or other debris, and is composed of sound A ggregate. D Granular Filter Under Class I Random Riprap D.1 Sizing Requirements Use Class 5 gradation requirements listed in Table 3138.2-3. D.2 Quality Requirements Provide virgin Aggregate meeting the requirements of 3138, “Aggregate for Surface and Base Courses.” E Granular Filter Under Other Riprap, Gabion, and Revet Mattress E.1 Sizing Requirements Meet the requirements of Table 3601.2-2. Table 3601.2-2 Granular Filter Material Sieve Size Percent Passing by Weight 6 inch 100 3 inch 75 – 100 1 inch 35 – 75 No. 4 10 – 40 No. 10 5 – 25 No. 40 0 – 15 No. 200 0 – 8 E.2 Quality Requirements Meet the requirements of 3149.2A.1, “Virgin Materials.” F Geotextile Filter Material Provide geotextile filter material, meeting the requirements of 3733, “Geosynthetic Materials” and the following:

(1)Type 3 for use under Class I and Class II random riprap

(2)Type 4 for use under Class III and Class IV random riprap and hand- placed

riprap on slopes no steeper than 3:1, horizontal to vertical

(3)Type 7 for use under Class III and Class IV random riprap on slopes steeper than

3:1, horizontal to vertical, and under Class V random riprap

3601.3SAMPLING AND TESTING

Sample and test at the rates specified in the Schedule of Materials Control . The Department will inspect the Material for compliance to the requirements of this section. Obtain the Engineer’s approval of the quality of the stone before delivering the stone to the P roject. The Engineer will inspect the stone for compliance to the gradation requirements after delivery of the stone to the Project. The Department may inspect and reject Material for compliance at any time. An approved Quality Control Program is required for riprap derived from Carbonate quarries if used for Bridge protection or quantities greater than 100 cubic yards. The Quality Control program is administered by the MnDOT Geology Unit. If the quantity of riprap for any class is greater than 40 cubic yards, the Engineer may require construction of a control unit consisting of 4 cubic yards of riprap as a reference for size and quality compliance. Construct the control unit at the source or on the Project. When the Engineer requires and approves a control unit for reference, maintain the control unit during riprap construction and incorporate the stones from the control unit as the last stones placed in the riprap construction. Use production stone equivalent to the stone placed in the approved control unit. A Riprap Gradation Test Method Using D 85 ............................................. Grading and Base Manual 5-692.210 B Riprap Gradation Test Method Using Wolman Count .......... Grading and Base Manual 5-692.211 C Riprap Gradation Test Method Using FHWA Hydraulic Toolbox .......... Grading and Base Manual 5-692.212 D Sieve Analysis ...............................................................Laboratory Manual Method 1202 & 1203 E Insoluble Residue ..................................................................... Laboratory Manual Method 1221

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Source: Minnesota Standard Specifications for Construction, 2025 Edition. Pages 977–0 of 1,081. View official source ↗

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3592 Drop-On Glass Beads

3602 Gabions and Revet Mattresses Materials

3601Riprap Material

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