1、Designation: D6473 10Standard 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 last rev
2、ision. 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 specificgravity and absorption of rock for erosion control, commonlyreferred to
3、as riprap or armor stone. The specific gravity maybe expressed as bulk specific gravity or apparent specificgravity. Bulk specific gravity and absorption are based on a24 6 4-h soaking time for the rock specimens tested.1.2 The use of reclaimed concrete and other materials isbeyond the scope of this
4、 test method.1.3 The values stated in SI units are to be regarded as thestandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and de
5、termine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C127 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Coarse AggregateD653 Terminology Relating to Soil, Rock, and ContainedFluidsD3740 Practice for Minimum Requ
6、irements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4753 Guide for Evaluating, Selecting, and SpecifyingBalances and Standard Masses for Use in Soil, Rock, andConstruction Materials TestingD4992 Practice for Evaluation of Rock to b
7、e Used forErosion ControlE145 Specification for Gravity-Convection and Forced-Ventilation Ovens3. Terminology3.1 DefinitionsDefinitions for terms in this test methodshall be in accordance with Terminology D653 except as notedin 3.2.3.2 Definitions of Terms Specific to This Standard:3.2.1 absorptiont
8、he increase in the mass of rock due towater in the pores of the material, but not including wateradhering to the outside surface of the particles. Absorption isexpressed as a percentage of the dry mass.3.2.2 apparent specific gravitythe ratio of the mass in airof a given volume of the impermeable po
9、rtion of a permeablematerial (that is, the solid matter including its impermeablepores or voids) at a stated temperature to the mass of an equalvolume of distilled water at the same stated temperature. Thevalue is dimensionless.3.2.3 bulk specific gravitythe ratio of the mass in air of agiven volume
10、 of a permeable solid (including both permeableand impermeable voids within the material) at a stated tem-perature, to the mass in air of an equal volume of distilledwater at the same stated temperature. The value is dimension-less.3.2.4 bulk specific gravity (saturated surface-dry) (SSD)the ratio o
11、f the mass of a given volume of permeable solid,(including the mass of water within the saturated permeablevoids) filled to the extent achieved by submerging in water forapproximately 24 h at the stated temperature to the mass of anequal volume of water at the same stated temperature. Thevalue is di
12、mensionless.3.2.5 specific gravitythe ratio of the mass in air of a givenvolume of solid at a stated temperature to the mass of an equalvolume of distilled water at the same stated temperature. Thevalue is dimensionless.4. Summary of Test Method4.1 An air-dried specimen (block, chunk, or slab) of ro
13、ck issubmerged in water for 24 6 4 h after which it is weighedwhile still submerged. It is then removed from the water, driedto a surface dry condition, and weighed again. Finally it is1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility o
14、f Subcommittee D18.17 on Rock for ErosionControl.Current edition approved Oct. 1, 2010. Published November 2010. Originallyapproved in 1999. Last previous edition approved in 2005 as D6473 - 99(2005).DOI: 10.1520/D6473-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontac
15、t ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West C
16、onshohocken, PA 19428-2959, United States.dried in an oven for a specified length of time and weighedagain. The initial mass and increase in mass are used todetermine the specimens specific gravity and percentage ofwater absorbed.NOTE 1Immersion durations other than the 24-h period have beenused. Sp
17、ecimens in those tests have been immersed in increments over afour-day period. Test results indicate a higher percentage of waterabsorption than the 24 h test. Negligible differences in bulk specificgravity were measured after one-day soaking and four-day incrementalsoakings.5. Significance and Use5
18、.1 Rock riprap and armor stone are composed of pieces ofnatural rock that are placed on construction projects, shore-lines, streambeds, bridge abutments, pilings, and other struc-tures to minimize the effects of erosion. The ability of rock towithstand deterioration from weathering affects both the
19、effec-tiveness of the project and its cost. The specific gravity andabsorption of rock provide useful information that can be usedin evaluating possible deterioration of rock.5.2 Bulk specific gravity and bulk specific gravity SSD mayreflect the quality of rock and is important in that it mayprovide
20、 one indicator to the resistance of a rock to movementby water.5.3 The absorption of water into rock may affect its dura-bility under freezing conditions and salt crystallization condi-tions. In addition, the absorption test has been used as an indextest in determining whether additional tests are n
21、eeded toevaluate the durability of a rock.5.4 Test specimens equal in size to the proposed design sizewould provide the best correlations between laboratory testsand actual field performance, however this is usually neitherpractical nor economically feasible.5.5 The results of these tests are not to
22、 be used as the solebasis for determination of rock durability, but should be used inconjunction with the results of other tests.5.6 These test methods have been used to evaluate differenttypes of rocks. There have been rare occasions when testresults have provided data that have not agreed with the
23、durability of rock under actual field conditions. For example,some rocks with low absorption values have fragmented inactual usage and some with high absorption values have provento be durable.NOTE 2The quality of the result produced by this test method isdependent on the competence of the personnel
24、 performing it, and thesuitability of the equipment and facilities used. Agencies which meet thecriteria of Practice D3740 are generally considered capable of competentand objective testing/sampling/inspection/etc. Users of this test methodare cautioned that compliance with Practice D3740 does not i
25、n itselfassure reliable results. Reliable results depends on many factors; PracticeD3740 provides a means of evaluating some of those factors.6. Apparatus6.1 BalanceA balance or scale conforming to the require-ments of Specification D4753 and readable (with no estima-tion) and accurate to the neares
26、t5gorto0.1%orbetter of themass of the test specimen. The balance shall be equipped withsuitable apparatus for suspending the sample container in waterfrom the center of the platform or pan of the balance.6.2 Specimen ContainerA wire basket capable of holdingthe submerged rock specimen being tested.
27、The container shallbe constructed so as to prevent trapping air when the containeris submerged.6.3 Water TankA watertight tank capable of holding thefully immersed rock and specimen container while suspendedbelow the balance.6.4 Drying OvenVented, thermostatically-controlled,preferably of the forced
28、-draft type, meeting requirements ofSpecification E145 and capable of maintaining a uniformtemperature of 110 6 5C (230 6 9F) throughout the dryingchamber.7. Sampling7.1 Practice D4992 provides guidance on sampling a sourceof rock. A source that is macroscopically uniform in color,texture, mineralog
29、y, or some other visual property shall berepresented by a sample consisting of a minimum of fivespecimens of rock. A macroscopically non-uniform sourceshall be represented by a sample consisting of a minimum ofeight specimens of rock for testing. Rock types that compriseless than 5 % of the total so
30、urce, as determined from theirmacroscopic properties may be ignored, unless their presencewill greatly affect the test results and subsequent proposed useof the rock. Sample the rock types in their approximateproportion to the types that occur at the source.7.2 Specimens shall be clean and without s
31、oil particles orother adherent materials. Specimens shall have all loose partsand adherent material removed by brushing with a stiff brush(including the use of water, as necessary) and shall be allowedto air dry.7.3 Each specimen shall be a minimum of 1 kg (2.2 lb) inmass. The maximum mass shall be
32、limited only by the capacityof the scale and size of the water-filled tank.NOTE 3Tests to determine the absorption and specific gravity havebeen performed on aggregate-sized particles in accordance with TestMethod C127. Larger-sized particles may include more variability in rockproperties than small
33、 particles and can give a better indication of the bulkproperties than small ones.8. Procedure8.1 Conduct the testing procedure at ambient laboratorytemperatures.8.2 Completely submerge the air-dried specimens, onespecimen at a time, in water at 20 to 30C (68 to 86F) for aperiod of 24 6 4 h. Place t
34、he soaked test specimen in thesuspended specimen container. Take care to remove all en-trapped air before determining its apparent mass in water byshaking the container while immersed. Determine and recordthe mass of each specimen as the buoyant mass, C. Record this,and all subsequent masses, to the
35、 nearest5gor0.1%,whichever is more precise.NOTE 4Care should be taken to ensure that any material detachedfrom its parent specimen during the immersion process shall remain withits parent specimen throughout the balance of testing. The detachedmaterial shall be treated and its mass determined, as wi
36、th the parentspecimen.8.3 Remove each specimen from the water and roll it in alarge absorbent cloth until all visible films of water areD6473 102removed. A moving stream of air (but not a heated air stream,such as from a drier) may be used to assist the drying. Takecare to avoid evaporation of water
37、 from the pores during thesurface drying operation. Determine and record the mass ofeach specimen as the saturated-surface dry mass, B.8.4 Dry each specimen for a minimum of 24 h or to aconstant mass within 60.1 % at a temperature of 110 6 5C(230 6 9F), then cool them in air at room temperature for
38、1 to3 h. Determine and record the mass of each specimen as theoven-dry mass, 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 andshall stand for several hours to dissipate any dissolved air. Laboratory testresult
39、s run on specimens tested in distilled water were sufficiently close tothose tested in tap water so as not to significantly affect the result.9. Calculation9.1 Calculate the bulk specific gravity, bulk specific gravity(SSD), apparent specific gravity, and absorption for eachspecimen at ambient labor
40、atory temperature as follows:bulk specific gravity 5 A/BC! (1)bulk specific gravity SSD!5 B/BC! (2)apparent specific gravity 5 A/AC! (3)absorption, % 5 BA!/A3 100 (4)where:A = mass of oven-dry test specimen in air, g,B = mass of saturated-surface dry test specimen in air, g,andC = buoyant mass of su
41、bmerged test specimen in water, g.9.1.1 Calculate the results for each specific gravity test tothe nearest 0.01. Calculate the averages of all specific gravitytests by summing the results of all test specimens and dividingby the number of specimens tested and report to the nearest0.01.9.1.2 Calculat
42、e the results for each absorption test to thenearest 0.1 %. Calculate the averages for all absorption tests bysumming the results of all specimens and dividing by thenumber of specimens and report to the nearest 0.1 %.10. Report10.1 Report the following information:10.1.1 Prepare a separate report o
43、n rock from each source.Report the source of the samples, its location, the datessampled and tested, and the geological formation if known,10.1.2 Description and type of materials,10.1.3 Name of the individuals performing the test,10.1.4 Indicate the type of specific gravity, whether bulk,bulk (SSD)
44、, or apparent. The specific gravity results for eachspecimen tested and the average of each type of test to thenearest 0.01, and10.1.5 Absorption result for each specimen tested and theaverage of all the specimens tested to the nearest 0.1 %.11. Precision and Bias11.1 PrecisionSubcommittee D18.17 is
45、 presently con-ducting a series of tests that it hopes will permit determiningprecision of test results. Subcommittee D18.17 welcomesproposals from the users of this test method that might be usedto make a limited statement on precision.11.2 BiasThere is no accepted reference value for this testmeth
46、od; therefore bias cannot be determined.12. Keywords12.1 absorption; riprap; rock material properties; specificgravitySUMMARY OF CHANGESCommittee D18 has identified the location of selected changes to this standard since the last issue(D6473 - 99(2005) that may impact the use of this standard. (Octo
47、ber 1, 2010)(1) Subsection 1.1, soak time was changed to more accuratelyreflect the allowable time range.(2) Subsection 5.1, additional uses of riprap and armor stonewere added to better define their usage.(3) Subsection 6.1, apparatus for balance, added the guidancethat the balance should be accura
48、te to its level of readability.Added the guidance that the balance should be equipped witha suitable apparatus to suspend a sample container beneath thebalance.(4) Subsection 6.2, apparatus for sample container, added theguidance that a container is required to contain the suspendedsample while subm
49、erged.(5) Subsection 6.3, apparatus for water tank, added the guid-ance that the tank must be capable of holding the fullyimmersed sample and sample container.(6) Subsection 6.4, apparatus for ovens, added the guidancethat the oven should be forced-draft and uniformly heatedthroughout the drying chamber.(7) Subsection 7.2 was revised to improve clarity.(8) Subsection 8.2 was revised to clarify the mass determina-tion of the suspended, submerged sample.D6473 103ASTM International takes no position respecting the validity of any patent rights assert
