1、Designation: D6473 10D6473 15Standard Test Method ForSpecific Gravity And Absorption of Rock For ErosionControl1This standard is issued under the fixed designation D6473; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of specific gravity and absorption of rock for erosion control, commonly re
3、ferredto as riprap or armor stone. The specific gravity may be expressed as bulk specific gravity or apparent specific gravity. Bulk specificgravity and absorption are based on a 24 6 4-h soaking time for the rock specimens tested. This test is appropriate for breakwaterstone, armor stone, riprap, a
4、nd gabion sized rock materials.1.2 The use of reclaimed concrete and other materials is beyond the scope of this test method.1.3 UnitsThe values stated in SI units are to be regarded as the standard. The values given in parentheses are mathematicalconversions to inch-pound units that are provided fo
5、r information only and are not considered standard.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in PracticeD6026, unless superseded by this standard.1.4.1 For purposes of comparing measured or calculated value(s) with specifie
6、d limits, the measured or calculated value(s) shallbe rounded to the nearest decimal or significant digits in the specified limits.1.4.2 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industrystandard. In addition, they are represen
7、tative of the significant digits that generally should be retained. The procedures used do notconsider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the users objectives;and it is common practice to increase or reduce significant digits of rep
8、orted data to be commensurate with these considerations.It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the respon
9、sibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C127 Test Method for Relative Density (Specific Gravity) and Absorption of Coarse AggregateD653 T
10、erminology Relating to Soil, Rock, and Contained FluidsD3740 Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used inEngineering Design and ConstructionD4753 Guide for Evaluating, Selecting, and Specifying Balances and Standard Masses for Use in
11、 Soil, Rock, and ConstructionMaterials TestingD4992 Practice for Evaluation of Rock to be Used for Erosion ControlE145D6026 Specification for Gravity-Convection and Forced-Ventilation OvensPractice for Using Significant Digits inGeotechnical Data3. Terminology3.1 DefinitionsDefinitions for terms in
12、this test method shall be in accordance with For definitions of common technical termsused in this standard, refer to Terminology D653 except as noted in 3.2.1 This test method is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.17 on
13、 Rock for ErosionControl.Current edition approved Oct. 1, 2010July 1, 2015. Published November 2010July 2015. Originally approved in 1999. Last previous edition approved in 20052010 asD6473 - 99D6473 - 10.(2005). DOI: 10.1520/D6473-10.10.1520/D6473-15.2 For referencedASTM standards, visit theASTM we
14、bsite, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indicat
15、ion of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be cons
16、idered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2 Definitions of Terms Specific to This Standard:3.2.1 absorptionthe increase in the mass
17、of rock due to water in the pores of the material, but not including water adheringto the outside surface of the particles. Absorption is expressed as a percentage of the dry mass.3.2.2 apparent specific gravitythe ratio of the mass in air of a given volume of the impermeable portion of a permeablem
18、aterial (that is, the solid matter including its impermeable pores or voids) at a stated temperature to the mass of an equal volumeof distilled water at the same stated temperature. The value is dimensionless.3.2.3 bulk specific gravitythe ratio of the mass in air of a given volume of a permeable so
19、lid (including both permeable andimpermeable voids within the material) at a stated temperature, to the mass in air of an equal volume of distilled water at the samestated temperature. The value is dimensionless.3.2.4 bulk specific gravity (saturated surface-dry) (SSD)the ratio of the mass of a give
20、n volume of permeable solid, (includingthe mass of water within the saturated permeable voids) filled to the extent achieved by submerging in water for approximately24 h at the stated temperature to the mass of an equal volume of water at the same stated temperature. The value is dimensionless.3.2.5
21、 gabion-fill stonestone generally less than 25 kg (50 lb) and placed in baskets of wire or other suitable material. Thesebaskets are then tied together to form an integral structure designed to resist erosion along stream banks and around bridge piers.3.2.6 specific gravitythe ratio of the mass in a
22、ir of a given volume of solid at a stated temperature to the mass of an equalvolume of distilled water at the same stated temperature. The value is dimensionless.4. Summary of Test Method4.1 An air-dried specimen (block, chunk, or slab) of rock is submerged in water for 24 6 4 h after which it its m
23、ass isweigheddetermined while still submerged. It is then removed from the water, dried to a surface dry condition, and weighed again.Finally its mass re-determined. Finally, it is dried in an oven for a specified length of time and weighed again. to a constant mass.The initial mass and increase in
24、mass are used to determine the specimens specific gravity and percentage of water absorbed.NOTE 1Immersion durations other than the 24-h period have been used. Specimens in those tests have been immersed in increments over a four-dayperiod. Test results indicate a higher percentage of water absorpti
25、on than the 24 h test. Negligible differences in bulk specific gravity were measured afterone-day soaking and four-day incremental soakings.5. Significance and Use5.1 Rock riprap and armor stone are composed of pieces of natural rock that are placed on construction projects, shorelines,streambeds, b
26、ridge abutments, pilings, and other structures to minimize the effects of erosion. The ability of rock to withstanddeterioration from weathering affects both the effectiveness of the project and its cost. The specific gravity and absorption of rockprovide useful information that can be used in evalu
27、ating possible deterioration of rock.5.2 Bulk specific gravity and bulk specific gravity SSD may reflect the quality of rock and is important in that it may provideone indicator to the resistance of a rock to movement by water.5.3 The absorption of water into rock may affect its durability under fre
28、ezing conditions and salt crystallization conditions. Inaddition, the absorption test has been used as an index test in determining whether additional tests are needed to evaluate thedurability of a rock.5.4 Test specimens equal in size to the proposed design size would provide the best correlations
29、 between laboratory tests andactual field performance, however this is usually neither practical nor economically feasible.5.5 The results of these tests are not to be used as the sole basis for determination of rock durability, but should be used inconjunction with the results of other tests.5.6 Th
30、ese test methods have been used to evaluate different types of rocks. There have been rare occasions when test resultshave provided data that have not agreed with the durability of rock under actual field conditions. For example, some rocks withlow absorption values have fragmented in actual usage a
31、nd some with high absorption values have proven to be durable.NOTE 2The quality of the result produced by this test method standard is dependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies which meet the criteria of Practice D37
32、40 are generally considered capable of competent andobjective testing/sampling/inspection/etc. Users of this test method standard are cautioned that compliance with Practice D3740 does not in itself assurereliable results. Reliable results depends on many factors; Practice D3740 provides a means of
33、evaluating some of those factors.6. Apparatus6.1 BalanceA balance or scale conforming to the requirements of Specification D4753 and readable (with no estimation) andaccurate to the nearest 5 g or to 0.1 % or better of the mass of the test specimen. The balance shall be equipped with suitableapparat
34、us for suspending the sample container in water from the center of the platform or pan of the balance.6.2 Specimen ContainerA wire basket capable of holding the submerged rock specimen being tested. The container shall beconstructed so as to prevent trapping air when the container is submerged.D6473
35、 1526.3 Water TankA watertight tank capable of holding the fully immersed rock and specimen container while suspended belowthe balance.6.4 An example apparatus is shown in Fig. 1.6.5 Drying OvenVented, thermostatically-controlled, preferably of the forced-draft type, meeting requirements of Specific
36、a-tion type E145and capable of maintaining a uniform temperature of 110 6 5C (230 6 9F) throughout the drying chamber.7. Sampling7.1 Practice D4992 provides guidance on sampling a source of rock.Asource that is macroscopically uniform in color, texture,mineralogy, or some other visual property shall
37、 be represented by a sample consisting of a minimum of five specimens of rock.A macroscopically non-uniform source shall be represented by a sample consisting of a minimum of eight specimens of rock fortesting. Rock types that comprise less than 5 % of the total source, as determined from their macr
38、oscopic properties may beignored, unless their presence will greatly affect the test results and subsequent proposed use of the rock. Sample the rock typesin their approximate proportion to the types that occur at the source.7.2 Specimens shall be clean and without soil particles or other adherent m
39、aterials. Specimens shall have all loose parts andadherent material removed by brushing with a stiff brush (including the use of water, as necessary) and shall be allowed to air dry.7.3 Each specimen shall be a minimum of 1 kg (2.2 lb) in mass. The maximum mass shall be limited only by the capacity
40、ofthe scale and size of the water-filled tank.NOTE 3Tests to determine the absorption and specific gravity have been performed on aggregate-sized particles in accordance with Test MethodC127. Larger-sized particles may include more variability in rock properties than small particles and can give a b
41、etter indication of the bulk propertiesthan small ones.8. Specimens8.1 Specimens shall be clean and without soil particles or other adherent materials. Specimens shall have all loose parts andadherent material removed by brushing with a stiff brush (including the use of water, as necessary) and shal
42、l be allowed to air dry.8.2 Each specimen shall be a minimum of 1 kg (2.2 lb) in mass. The maximum mass shall be limited only by the capacity ofthe scale and size of the water-filled tank.NOTE 3Tests to determine the absorption and specific gravity have been performed on aggregate-sized particles in
43、 accordance with Test MethodC127. Larger-sized particles may include more variability in rock properties than small particles and can give a better indication of the bulk propertiesthan small ones.9. Procedure9.1 Conduct the testing procedure at ambient laboratory temperatures.9.2 Completely submerg
44、e the air-dried specimens, one specimen at a time, specimens in water at 20 to 30C (68 to 86F) fora period of 24 6 4 h. Place the soaked test specimen specimen, one at a time, in the suspended specimen container. containerensuring it is completely immersed in water. The specimen container shall be i
45、mmersed to the same level (depth) as whendetermining the tare value to reduce error caused by the mass of the equipment above and below the water level. Take care toFIG. 1 Example ApparatusD6473 153remove all entrapped air before determining its apparent mass in water by shaking the container while
46、immersed. immersedcontainer. Determine and record the mass of each specimen as the buoyant mass, C. Record this, and all subsequent masses, tothe nearest 5 g or 0.1 %, whichever is more precise.NOTE 4Care should be taken to ensure that any material detached from its parent specimen during the immers
47、ion process shall remain with its parentspecimen throughout the balance of testing. The detached material shall be treated and its mass determined, as with the parent specimen.9.3 Remove each specimen from the water and roll it in a large absorbent cloth until all visible films of water are removed.
48、 Amoving stream of air (but not a heated air stream, such as from a drier) may be used to assist the drying. Take care to avoidevaporation of water from the pores during the surface drying operation. Determine and record the mass of each specimen as thesaturated-surface dry mass, B.9.4 Dry each spec
49、imen for a minimum of 24 h or to a constant mass within 60.1 % at a temperature of 110 6 5C (230 6 9F),then cool them in air at room temperature for 1 to 3 h. Constant mass will be considered to have been achieved when weight lossis less than 0.1 % of specimen weight in four hours of drying. Determine and record the mass of each specimen as the oven-drymass, A.NOTE 5The use of tap water instead of distilled water is permitted. The tap water shall not contain a high amount of dissolved minerals and shallstand for several hours to dissipate any dissolved ai
