1、Designation: C 1506 03Standard Test Method forWater Retention of Hydraulic Cement-Based Mortars andPlasters1This standard is issued under the fixed designation C 1506; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method provides for the determination of waterretention of hydraulic cement-based mortars and plasters.1.2 Thi
3、s 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 determine the applica-bility of regulatory limitations prior to use. (WarningFreshhydrauli
4、c cementitious mixtures are caustic and may causechemical burns to skin and tissue upon prolonged exposure.)22. Referenced Documents2.1 ASTM Standards:C 109/C 109M Test Method for Compressive Strength ofHydraulic Cement Mortars (Using 2-in. or 50-mm CubeSpecimens)3C 185 Test Method for Air Content o
5、f Hydraulic CementMortar3C 230 Specification for Flow Table for Use in Tests ofHydraulic Cement3C 305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic Consistency3C 670 Practice Preparing Precision and Bias Statements forTest Methods for Construction Materials4C 1437 T
6、est Method for Flow of Hydraulic Cement Mortar33. Summary of Test Method3.1 The flow of the mortar or plaster is determined. Themortar or plaster is then subjected to a controlled vacuumsuction for 60 s, after which the flow is again determined. Thewater retention is the final flow divided by the in
7、itial flowexpressed as a percentage.4. Significance and Use4.1 This test method provides a means for determining theability of mortars and plasters to retain water under suction.Test results may be used to determine compliance withspecifications.4.2 The results obtained using this test method can be
8、 usedto compare the relative ability of mortars and plasters to retainwater under suction.4.3 The results obtained using this test method for masonrymortars do not necessarily indicate the degree of waterretention when used with masonry units, since the amount ofwater absorbed by the unit depends on
9、 the rate of absorption ofthe masonry unit.4.4 The results obtained using this test method for plasters(stucco) do not necessarily indicate the degree of waterretention when the plaster is applied as a second coat on thesurface of a previously applied plaster base coat, since theamount of water abso
10、rbed from the second coat of plasterdepends on the rate of absorption of the base coat. This is alsotrue when a plaster is applied as a coating on masonry units.5. Apparatus5.1 Tamper, conforming to Test Method C 109/C 109M.5.2 Straightedge, conforming to Test Method C 185.5.3 Flow Table, conforming
11、 to Specification C 230.5.4 Mixing Apparatus, conforming to the requirements pre-scribed in Practice C 305.5.5 Filtration Assembly, an apparatus essentially as shownin Fig. 1 shall be used. This apparatus consists of a perforateddish resting on a funnel, which is connected by a three-waystopcock to
12、a vacuum flask, to which a controlled vacuum isapplied. The perforated dish shall be made of metal notattacked by masonry mortar or plaster (Note 1). The metal baseof the dish shall have a thickness of 2.0 6 0.3 mm and shallconform to the requirements given in Fig. 1. The stopcock boreshall have a 4
13、.0 6 0.5-mm diameter, and the connecting glasstubing shall have a minimum inside diameter of 4 mm. Thelength of the tubing projecting into the 1-L flask from thestopcock shall extend at least 25 mm below the center line ofthe vacuum connection. The contact surfaces of the funnel andperforated dish s
14、hall be plane and may need to be lapped to1This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct responsibility of Subcommittee C01.22 on Workability.Current edition approved Jan. 10, 2003. Published February 2003. Originallyapproved in 2001. Last previous editi
15、on approved in 2001 as C 150601.2Section on Safety, Manual of Cement Testing, Annual Book of ASTMStandards, Vol 04.01.3Annual Book of ASTM Standards, Vol 04.01.4Annual Book of ASTM Standards, Vol 04.02.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-295
16、9, United States.ensure intimate contact. An airtight seal shall be maintainedbetween the funnel and the dish during the test. This shall beaccomplished by either of the following procedures. (1)Asynthetic (grease-resistant) rubber gasket may be permanentlysealed to the top of the funnel using petro
17、latum or light greaseto ensure a seal between the gasket and dish. (2) The top of thefunnel may be lightly coated with petroleum or light grease toensure a seal between the funnel and dish. Care should be takento ensure that none of the holes in the perforated dish becomeclogged. Hardened, smooth, n
18、ot rapid filter paper shall be used.It shall be 150 mm in diameter and be placed so as tocompletely cover the perforations in the dish.NOTEThe gasket is to be synthetic rubber. The stopcock and the bore of the tubing shall be at least 4-mm. A check valve or water trap, or both, issuggested for the c
19、onnection to the vacuum source.FIG. 1 Apparatus Assembly for the Water-Retention TestC1506032NOTE 1Stainless steel, brass, and bronze are suitable metals for thispurpose.5.6 Controlled Vacuum Source:5.6.1 A vacuum gage capable of reading at least 9-kPapressure in 0.1-kPa increments (Note 2 and Note
20、3), connectedto a miniature vacuum regulator having a maximum 55-kPacapacity, which is then connected to a vacuum pump or wateraspirator as shown in Fig. 1. Connection is made between thevacuum flask and the vacuum gage.NOTE 2Vacuum values are all given as pressure relative to atmo-spheric pressure.
21、NOTE 3Gages reading pressure in other units are acceptable as longas their capacity and scale increments comply with the levels specifiedhere. (For example, a vacuum gage with a minimum capacity of 70 mmof Hg in 1-mm increments is acceptable. To convert mm of Hg to kPa,multiply by 0.1333. Thus the 7
22、.0-kPa starting pressure is equivalent to53-mm Hg.)6. Temperature and Humidity6.1 The temperature of the mixing room and the roomcontaining the water retention apparatus shall be maintained at23.0 6 4.0C. The relative humidity of the air shall not be lessthan 50 %.7. Materials7.1 The composition of
23、the mortar or plaster to be tested forwater retention shall be that described in the specification ofthe material being considered, or that desired.8. Mixing of Mortar and Plaster8.1 The mortar or plaster to be tested for water retentionshall be mixed as specified in the section on Procedure forMixi
24、ng Mortars of Practice C 305, or as described in thespecification for the material being considered.9. Procedure9.1 Preparation of ApparatusAdjust the vacuum to 7.0 60.4 kPa (Note 2). Seat the perforated dish on the greased gasketor greased rim of the funnel. Place a wetted filter paper in thebottom
25、 of the dish. Turn the stopcock to apply the vacuum tothe funnel and check the apparatus for leaks and to determinethat the required vacuum is obtained. Then turn the stopcock toshut off the vacuum from the funnel.9.2 Determination of FlowDetermine the flow in accor-dance with Test Method C 1437.9.3
26、 Preparation of Mortar or Plaster BedImmediatelyafter making the flow test, return the mortar or plaster on theflow table to the mixing bowl and remix the entire batch for 15s at medium speed. Immediately after remixing, fill theperforated dish with the material to slightly above the rim.Tamp 15 tim
27、es with the tamper. Apply ten of the tampingstrokes at approximately uniform spacing adjacent to the rim ofthe dish, and with the long axis of the tamping face held at rightangles to the radius of the dish. Apply the remaining fivetamping strokes at random points distributed over the centralarea of
28、the dish. Use just enough tamping pressure to fill thedish with the top of the material extending slightly above therim. Smooth off the material by drawing the flat side of thestraightedge (with the leading edge slightly raised) across thetop of the dish. Strike-off the material to a plane surface f
29、lushwith the rim of the dish with the straightedge held in aperpendicular position; using a sawing motion, draw thestraightedge across half of the surface of the dish; repeat theprocedure on the other half of the unfinished surface. If thematerial is pulled away from the side of the dish during thep
30、rocess of drawing the straightedge across the dish, gentlypress the material back into contact with the side of the dishusing the tamper. Complete the entire filling and strike-offoperation in not more than 2 min.9.4 Application of Vacuum to Mortar or PlasterTurn thestopcock to apply the vacuum to t
31、he funnel. After suction for60 s, quickly turn the stopcock to expose the funnel toatmospheric pressure.9.5 Determination of Flow After SuctionImmediatelyslide the perforated dish off the funnel, touch the bottom of thedish momentarily on a damp cloth to remove droplets of water.Set the dish on a wo
32、rk table, plow and mix the mortar or plasterfor 15 s, with the rubber scraper prescribed in Practice C 305.Determine the flow in accordance with Test Method C 1437.Remove the vacuum and complete the flow test in less than 2min.10. Calculation10.1 Calculate the water retention value for the mortar or
33、plaster as follows:Water retention, % 5 A/B! 3 100where:A = flow after suction, andB = flow immediately after initial mixing.Report to the nearest 1 %.11. Precision and Bias11.1 PrecisionThe following precision values were cal-culated from results of tests reported to Cement and ConcreteReference La
34、boratory (CCRL) for masonry cement proficiencysamples Number 3 through 42 (Note 4). Within- and among-laboratory standard deviations were calculated by CCRL foreach sample pair. Values were pooled over all 40 samples forpurposes of this analysis. Water retention test results (exclud-ing outliers) ra
35、nged from 72 to 88 %. The average number oflaboratories reporting was 69.NOTE 4These tests utilized a slightly different test pressure, 6.7 6 0.4kPa (50 6 0.3 mm Hg).11.1.1 Single-laboratory PrecisionThe single-laboratorystandard deviation has been found to be 3.5 % (Note 5).Therefore, the results o
36、f two properly conducted tests in thesame laboratory on the same material should not differ by morethan 9.8 % (Note 5) in 95 % of such pairwise comparisons.11.1.2 Multilaboratory PrecisionThe multilaboratorystandard deviation has been found to be 5.1 % (Note 5).Therefore, the results of two properly
37、 conducted tests indifferent laboratories on the same material should not differ bymore than 14.3 % (Note 5) in 95 % of such pairwise compari-sons.NOTE 5These numbers represent, respectively, the 1s and d2s limitsas described in Practice C 670.C150603311.2 BiasSince there is no accepted reference ma
38、terialsuitable for determining bias in this test method, no statementon bias is being made.12. Keywords12.1 hydraulic cement; mortar; plaster; water retentionASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standa
39、rd. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewe
40、d every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible
41、technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C1506034
