ASTM_C_243_-_95.pdf

Designation:C 243 95Standard Test Method forBleeding of Cement Pastes and Mortars1This standard is issued under the fixed designation C 243;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last 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 covers the determination of the bleed-ing rate and bleeding capacity of cement paste and mortar.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 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 determine the applica-bility of regulatory limitations prior to use.For specific hazardstatements,see Section 5.2.Referenced Documents2.1 ASTM Standards:C 109 Test Method for Compressive Strength of HydraulicCement Mortars(Using 2-in.or 50-mm Cube Specimens)2C 230 Specification for Flow Table for Use in Tests ofHydraulic Cement2C 305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic Consistency2C 778 Specification for Standard Sand2C 1005 Specification for Weights and Weighing Devices forUse in the Physical Testing of Hydraulic Cements23.Significance and Use3.1 This test method is intended primarily for use by thoseinterested in research into the relative bleeding characteristicsof cement pastes and mortars.4.Apparatus4.1 Weights and Weighing DevicesThe weights andweighing devices shall conform to the requirements of Speci-fication C 1005.The weighing device shall have a capacity ofat least 5000 g and shall be evaluated for precision andaccuracy at a total load of 5000 g.4.2 TamperThe tamper shall be made of a nonabsorptive,nonabrasive material such as medium-hard rubber or seasonedoak wood rendered nonabsorptive by immersion for 15 min inparaffin at approximately 200C(392F),and shall have a crosssection of 13 by 25 mm(12by 1 in.)and a convenient length(127 or 152 mm(5 or 6 in.).The tamping face of the tampershall be flat and at right angles to the length of the tamper.4.3 Liquid Displacement Bleeding Apparatus3The bleed-ing apparatus shall consist of a container for the paste or mortarto be tested,a collecting ring(Note 1),and a measuring buretwith funnel,as illustrated in Fig.1.The container shall be madeof noncorroding metal,127 mm(5 in.)in diameter and 102 mm(4 in.)in height.An outer ring 152 mm(6 in.)in diameter shallbe soldered to the perimeter of the cup 12.7 mm(0.5 in.)belowthe top rim of the cup and extended 38 mm(1.5 in.)above therim.The collecting ring shall be 76 mm(3.0 in.)in insidediameter,flanged as shown in Fig.1,to direct the rising waterinto the funnel,and bevelled on the lower rim as shown in thelower left insert of Fig.1 to trap only the rising water withinthe area of the 76-mm diameter ring.This ring shall be madeof noncorroding metal and shall be centered and supported atthe proper depth by brackets as shown in Fig.1.The containerand ring shall be of sufficient thickness and rigidity to maintaintheir shape under normal handling.The funnel and buretassembly shall be made of glass and so joined that there will beno rough edges to inhibit the rise of the water into the buret.The outside diameter of the funnel shall be 73.7 mm(2.9 in.).The rim of the funnel shall be ground on a plane parallel to theaxis of the funnel and buret,but the resulting edge shall berounded.The buret shall be of 25-mL capacity and not over460 mm in over-all length.The constricted capillary,stopcock,and aspirator may be connected to the top of the buret througha suitable rubber stopper.The buret assembly shall be sup-ported by a ring stand or similar equipment so that it can beconveniently raised or lowered over the collecting ring andheld rigidly in place during the test period.NOTE1At times,water bubbles rise up the outside wall of thecollecting ring and enter the buret.It has been found that a band of inertepoxy put around the outside of the collecting ring blocks these bubblesand prevents them entering the buret.4.4 Mechanical MixerA mechanical mixer shall be usedthat conforms to the requirements of Practice C 305.1This test method is under the jurisdiction of ASTM Committee C-1 on Cementand is the direct responsibility of Subcommittee C01.22 on Workability.Current edition approved Nov.10,1995.Published January 1996.Originallypublished as C 243 50 T.Last previous edition C 243 85(1989).2Annual Book of ASTM Standards,Vol 04.01.3The application of the liquid-displacement principle to the collection andcontinuous measurement of bleeding water is due to R.C.Valore,Jr.of the NationalInstitute of Standards and Technology,Washington,DC,who,with the collaborationof colleagues J.E.Bowling and R.L.Blaine,developed