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Designation: D6825 −02 (Reapproved 2008)´1 Standard Guide for Placement of Ripr

Designation: D6825 −02 (Reapproved 2008)´1 Standard Guide for Placement of Riprap Revetments1 This standard is issued under the ﬁxed designation D6825; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval. ´1 NOTE—Sections X1.1-X1.3 were corrected editorially in February 2008. 1. Scope 1.1 This guide covers methods to place riprap with associ- ated ﬁlters for erosion control purposes. This guide does not recommend a speciﬁc course of action because of the diverse methods and procedures that are capable of producing a functional product. This guide identiﬁes favorable riprap quali- ties and recommends practices best suited to obtain those qualities. The production of rock, use of recycled materials, rock with cut dimensions, and engineering and design is beyond the scope of this guide. Special forms of riprap, including hand placed riprap, grouted riprap, or keyed (plated) riprap that is tamped into place to smooth the surface, are also beyond the scope of this guide. 1.2 This guide offers an organized collection of information or a series of options and does not recommend a speciﬁc course of action. This document cannot replace education or experi- ence and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to repre- sent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been developed and approved through the ASTM consensus process 1.3 This standard may involve hazardous operations and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety and health practices and determine the applica- bility of regulatory requirements prior to use. 2. Referenced Documents 2.1 ASTM Standards:2 C33 Speciﬁcation for Concrete Aggregates C136 Test Method for Sieve Analysis of Fine and Coarse Aggregates D75 Practice for Sampling Aggregates D653 Terminology Relating to Soil, Rock, and Contained Fluids D4992 Practice for Evaluation of Rock to be Used for Erosion Control D5519 Test Methods for Particle Size Analysis of Natural and Man-Made Riprap Materials D6092 Practice for Specifying Standard Sizes of Stone for Erosion Control 2.2 AASHTO Standard:3 M 288–2000 Geotextile Speciﬁcation for Highway Applica- tions 3. Terminology 3.1 Terminology used in this guide, which is not included or not completely deﬁned in Terminology D653, is deﬁned below. 3.2 Deﬁnitions of Terms Speciﬁc to This Standard: 3.2.1 bedding—an aggregate mixture placed below the rip- rap. Bedding material is usually sand and gravel sized, but may include cobble sized material. If placed without a geotextile, the bedding material may be used as a ﬁlter. If placed in conjunction with a geotextile, the bedding may provide a cushion for protection of the geotextile during riprap placement and provide conﬁnement of the geotextile. It is possible to have more than one bedding layer. 3.2.2 chinking—the practice of ﬁlling riprap surface voids with smaller sized rock or aggregate. 1 This guide is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.17 on Rock for Erosion Control. Current edition approved Jan. 1, 2008. Published February 2008. Originally approved in 2002. Last previous edition approved in 2002 as D6825 – 02´2. DOI: 10.1520/D6825-02R08E01. 2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website. 3 Available from American Association of State Highway and Transportation Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001, http://www.transportation.org. Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States 1 3.2.3 clam shell—a bucket tool that is operated from a dragline or crane. The bucket is hinged at the top and opens like a clam so that rock can be placed without dropping it. 3.2.4 Dx—the particle diameter at which x % by weight (dry) of the particles of a particular sample are ﬁner. 3.2.5 ﬁlter—any substance, as geotextile or layer of sand/ aggregate, placed to provide separation and retention of mate- rials, while allowing water to pass. 3.2.6 ﬂoater—a individual rock within the riprap layer that is not interlocked with the surrounding rocks. 3.2.7 maximum aspect ratio—the ratio of the greatest to the least dimension, measured across mutually perpendicular axes, for any piece of rock; synonym, slabbiness. 3.2.8 orange peel—a bucket tool that is operated from a dragline or crane and resembles the shape of an orange peeling. The sides lift up and out so that rock can be placed without dropping it. 3.2.9 pit run material—rock that has been blasted but not processed to remove undersize pieces; synonym, shot rock or quarry run. 3.2.10 revetment—bank protection by armor, that is, by facing of a bank or embankment with erosion-resistant mate- rial. 3.2.11 riprap—material generally less than 2 tons (1.8 tonnes) in mass, specially selected and graded. When properly placed, riprap prevents erosion through minor wave action, or strong currents and thereby preserves the shape of a surface, slope, or underlying structure. Riprap may be speciﬁcally produced for the intended purpose, or it may be a by-product from a mining operation, structure demolition, or industrial process. 3.2.12 rock—any naturally formed aggregate of mineral matter occurring in large masses or fragments. Rock may be either insitu or excavated material. 4. Signiﬁcance and Use 4.1 Riprap is a commonly used form of scour protection and general slope protection. Riprap provides a long term solution when properly sized and installed. Riprap has structural ﬂex- ibility so it will conform to irregular surfaces and adapt to minor subgrade settlement. It is often appropriate for use in conjunction with soil bioengineering (vegetation establish- ment) alternatives. In some environments, riprap may provide habitat for benthic organisms and ﬁsh. 4.2 Revetments provide a facing or lining to armor a surface; and the layer thickness is typically minimized while providing the necessary resistance to scour. In this case, standardized practices to obtain consistent coverage having acceptable thickness tolerances and voids become important. 4.3 This guide may be used by owners, installation contrac- tors, regulatory agencies, inspection organizations, and design- ers and speciﬁers who are involved in the construction of riprap revetments. Modiﬁcations may be required for speciﬁc job conditions.This guide is not intentded for construction speci- ﬁcations on large projects, but may be referenced where preparation of job speciﬁc construction speciﬁcations are not justiﬁed. If this practice is included by reference in contract documents, the speciﬁer must provide a list of supplemental requirements. 5. Planning for Riprap Placement 5.1 Site conditions, level of protection required, construc- tion methods, and equipment may affect the sizing, thickness, and lateral extent of a riprap revetment. For some small projects, riprap may be dumped with minimal analysis or quality control, and still fulﬁll the intended purpose. For larger projects and critical structures, engineering, careful placement, and quality control become increasingly justiﬁed to minimize material costs and reduce the chance of failure. The degree of control appropriate should be appropriate for each project. The methods for placement and quality control should be compat- ible with the level of site investigation and other considerations included in Table 1. Table 1 includes factors which should be considered, but are beyond the scope of this guide. Some recommended publications for further information on these factors and engineering criteria are given in the References section. Designing the revetment is beyond the scope of this guide. NOTE 1—Slope stability should always be considered. If it is not investigated analytically by a qualiﬁed professional, then it should at least be considered subjectively in light of the site conditions and surrounding conditions (riverbanks, shorelines, or landforms). Many agencies have generalized maximum allowable slopes (usually in the range of 1.5H:1V to 3H:1V); however, these must be recognized as site speciﬁc. Limitations of the foundation, bank, material interfaces, seepage conditions, or toe scour may lead to instability. 6. Riprap Materials 6.1 Stone Sources and Evaluation—Rock must be durable material. In some cases, a source may be established based on rock classiﬁcation, geologic evaluation, and observations of existing installations showing that the rock is durable. If a history of rock durability is not established, sampling and testing the rock may be required. Acceptable material proper- ties for rock is dependent on the conditions (such as abrasion and saturation frequency due to wave run-up) and climate in the vicinity of where it will be used. Source selection must also consider the material properties available from local sources. Riprap is uploads/Ingenierie_Lourd/ guide - 2023-05-31T015238.069.pdf