ASTM C1435 C1435M-2014 Standard Practice for Molding Roller-Compacted Concrete in Cylinder Molds Using a Vibrating Hammer《用振动锤在混凝土模具中模塑碾实混凝土的标准实施规程》.pdf

《ASTM C1435 C1435M-2014 Standard Practice for Molding Roller-Compacted Concrete in Cylinder Molds Using a Vibrating Hammer《用振动锤在混凝土模具中模塑碾实混凝土的标准实施规程》.pdf》由会员分享，可在线阅读，更多相关《ASTM C1435 C1435M-2014 Standard Practice for Molding Roller-Compacted Concrete in Cylinder Molds Using a Vibrating Hammer《用振动锤在混凝土模具中模塑碾实混凝土的标准实施规程》.pdf（5页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: C1435/C1435M 14Standard Practice forMolding Roller-Compacted Concrete in Cylinder MoldsUsing a Vibrating Hammer1This standard is issued under the fixed designation C1435/C1435M; the number immediately following the designation indicates theyear of original adoption or, in the case of re

2、vision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice2covers molding cylindrical test specimensfrom concrete when the standard procedures

3、 of rodding andinternal vibration, as described in Practice C31/C31M andPractice C1176/C1176M, are not practicable. This practice isapplicable to freshly-mixed concrete, prepared in the labora-tory and the field.1.2 Freshly-mixed concrete is molded in cylindrical moldsusing an electric vibrating ham

4、mer equipped with a shaft andcircular plate.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. Within the text, theinch-pound units are shown in brackets. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be

5、used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 The text of this practice references notes and footnotes,which provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be consider

6、edas requirements of this practice.1.5 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 limit

7、ations prior to use.2. Referenced Documents2.1 ASTM Standards:3C31/C31M Practice for Making and Curing Concrete TestSpecimens in the FieldC39/C39M Test Method for Compressive Strength of Cylin-drical Concrete SpecimensC172/C172M Practice for Sampling Freshly Mixed Con-creteC470/C470M Specification f

8、or Molds for Forming ConcreteTest Cylinders VerticallyC496/C496M Test Method for Splitting Tensile Strength ofCylindrical Concrete SpecimensC1170/C1170M Test Method for Determining Consistencyand Density of Roller-Compacted Concrete Using a Vi-brating TableC1176/C1176M Practice for Making Roller-Com

9、pactedConcrete in Cylinder Molds Using a Vibrating Table2.2 ACI Documents:ACI 207.5R Report on Roller-Compacted Concrete4ACI 211.3 Practice for Selecting Proportions for No-SlumpConcrete43. Summary of Practice3.1 This practice describes molding cylindrical concrete testspecimens using a vibrating ha

10、mmer. Test specimens aremolded vertically in cylindrical molds by compacting the stiffto very dry concrete mixture in four lifts using a vibratinghammer.4. Significance and Use4.1 This practice, intended for use in testing roller-compacted concrete, may be applicable to testing other types ofcementi

11、tious material such as coarse-grained, soil-cement. Thispractice provides standardized requirements for molding stiffto very dry consistency concrete mixtures commonly used inroller compacted concrete construction. This practice is usedinstead of rodding or internal vibration, which cannot properlyc

12、onsolidate concrete of this consistency.NOTE 1Further description of roller compacted concrete consistencyis given in ACI 207.5R and ACI 211.3. The consistency of concrete using1This practice is under the jurisdiction of Committee C09 on Concrete andConcrete Aggregates and are the direct responsibil

13、ity of Subcommittee C09.45 onRoller-Compacted Concrete.Current edition approved Oct. 1, 2014. Published November 2014. Originallyapproved in 1999. Last previous edition approved in 2008 as C1435/C1435M 08.DOI: 10.1520/C1435_C1435M-14.2Supporting data have been filed at ASTM International Headquarter

14、s and maybe obtained by requesting Research Report RR:C09-1045. ContactASTM CustomerService at serviceastm.org.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the s

15、tandards Document Summary page onthe ASTM website.4ACI Manual of Concrete Practice, Part 1, Materials and General Properties ofConcrete, American Concrete Institute, Farmington Hills, MI.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Dr

16、ive, PO Box C700, West Conshohocken, PA 19428-2959. United States1a vibrating table may be determined in accordance with Test MethodsC1170/C1170M.4.2 This practice is used to mold cylindrical test specimenscommonly used for testing compressive or tensile strength ofconcrete. Specimens tested for com

17、pressive strength and split-ting tensile strength shall be in accordance with Test MethodsC39/C39M and C496/C496M, respectively. Test specimensalso may be used to determine density of fresh concrete.NOTE 2For some extremely dry mixtures; (those with a consistencygreater than 45 s when tested in acco

18、rdance with Test Methods C1170/C1170M)5the density of specimens made in accordance with this practicemay be greater than the in-place density of roller-compacted concrete dueto the greater potential for voids at the bottom of the lifts in the field.NOTE 3The mass of the apparatus and amount of force

19、 applied by theoperator may significantly affect the density of specimens made fromthese mixtures; thus, discretion is advised when interpreting test results onspecimens made according to this practice.5. Apparatus5.1 Molds:5.1.1 Type A Reusable MoldA cylindrical mold conform-ing to the requirements

20、 of Specification C470/C470M for150-mm 6-in. diameter by 300-mm 12-in. high reusablemolds.5.1.2 Type B Single-Use MoldA single-use plastic, cylin-drical mold 150-mm 6-in. diameter and 300-mm 12-in. inheight. The mold specifications shall conform to SpecificationC470/C470M for single-use, plastic mol

21、ds.5.1.2.1 Mold SleeveA Type B cylindrical mold shall beinserted into a rigid cylindrical sleeve. The cylindrical sleeveshall be made of steel or other hard metal resistant to cementpaste corrosion. The sleeve shall be capable of firmly holdingthe plastic mold upright without deformation of the mold

22、. Thesleeve shall be split and hinged on one side so that it can beopened to remove the plastic mold; adjustable clamps shall beprovided on the other side for tightening the sleeve around themold. A metal base plate with brackets shall be provided inwhich to insert the bottom portion of the sleeve t

23、o hold thesleeve during compaction. The sleeve shall have a minimumwall thickness of 3 mm 18 in., and a minimum base platethickness of 6 mm 14 in. The inside diameter of the moldsleeve shall be 3 6 1mm18 6116 in. larger than the outsidediameter of the Type B mold and have a height 13 6 6mm12614 in.

24、less than the height of the Type B mold.5.2 Vibrating HammerA vibrating compaction hammerhaving a mass (without tamping plate and shaft) of 8.5 to 13.5kg 19 to 30 lb. It also shall have a minimum power input of900 W and be capable of providing 2000 6 200 impacts/min.NOTE 4The vibrating hammer used t

25、o compact the specimens, such asshown in Fig. 1, is of the type used typically for breaking up concrete andmasonry. It provides oscillatory motion in the axial direction that makesthe hammer an effective vibratory compactor.5.3 Tamping PlateA circular steel plate attached to a steelshaft, which is i

26、nserted into the vibrating hammer chuck. Theplate diameter shall be 146 6 3mm534 618 in. and themass of the plate and shaft assembly shall be 3 6 1 kg 6.6 62.2 lb (See Fig. 2).5.4 Small ToolsA square-ended shovel, a hand scoop, atamping rod, and a stopwatch.6. Sampling6.1 Samples of freshly-mixed co

27、ncrete shall be obtained inaccordance with Practice C172/C172M.6.2 Concrete samples shall have a maximum size aggregateof 50 mm 2 in. or less. If the concrete has aggregate largerthan 50 mm 2 in. samples shall be obtained by wet sievingover a 50-mm 2-in. sieve in accordance with PracticeC172/C172M.6

28、.3 Concrete test specimens shall be molded within 45 minafter the completion of mixing unless otherwise specified.6.4 Technical Precautions:6.4.1 When obtaining samples, ensure that the samples arerepresentative of the bulk production.6.4.2 Concrete with stiff to very dry consistency is highlysuscep

29、tible to segregation during handling. To minimizesegregation, use care in obtaining samples and duringtransporting, remixing, and preparation of the specimens.7. Calibration7.1 Calibrate the vibrating hammer after any event, includ-ing repairs, that might affect its operation, after 300 h ofservice,

30、 or at least one time per year.8. Molding Specimens8.1 Type A Molds:8.1.1 Coat Type A molds with a suitable lubricant or bondbreaker prior to casting the test specimens to facilitate removalfrom the mold.8.2 Type B Molds:8.2.1 Insert Type B mold into the mold sleeve and adjust theclamps to tighten t

31、he sleeve around the mold so that the moldis held firmly in the sleeve.8.3 Type A and B Molds:8.3.1 Hold the mold stationary either by clamping to a rigid,flat base or standing on the foot brackets and center thevibrating hammer so that the edges of the tamping plate do nottouch the walls of the mol

32、d. Lower the vibrating hammer intothe mold to check for proper clearance.8.3.2 Place enough concrete in the mold so that the moldwill be filled to one-fourth of its volume after consolidation,approximately 3.4 kg 7.5 lb. Use a tamping rod to distributethe loose concrete as it is added. During fillin

33、g, use square-ended shovels and scoops to obtain representative samples andhandle the concrete in such a manner that larger sized coarseaggregates do not separate from the mortar.8.3.3 Place the vibrating hammer with tamping plate ontothe concrete (Fig. 1).8.3.4 Start the vibrating hammer and allow

34、the concrete toconsolidate under the tamping plate. Observe the concrete inthe annular space between the edge of the tamping plate and5Hansen, K. and Kahler, C., “RCC Tests, Testing, and Test Sections LessonsLearned,” The Journal of Dam Safety, Volume 2, Issue 1 (Winter 2004), p.14C1435/C1435M 142th

35、e inside wall of the mold. As the concrete consolidates,mortar should fill in the annular space between the outer edgeof the tamping plate and the inside mold wall. Observe themortar until it forms a ring around the total perimeter of thetamping plate. When the mortar ring forms completely aroundthe

36、 tamping plate, stop the vibrating hammer.8.3.5 If a rock or rock pocket prevents the mortar ring fromforming at one small location, even though it has formed in allother locations, the vibrating hammer can be stopped and thenext layer of concrete added.8.3.6 If a significant portion of the mortar r

37、ing does not formafter 20 s, the vibrating hammer shall be stopped and the nextlayer of concrete added. This situation may be a result ofinsufficient mortar due to either improper sampling,segregation, or improper mixture proportioning. In theseinstances, the concrete should be inspected visually af

38、terstripping from the mold to determine if there is adequatemortar distribution and a decision made whether to accept orreject the specimen.8.3.7 Repeat the procedure in 8.3.2 8.3.6 for the secondand third lifts of concrete, filling the mold to approximatelyone-half and three-fourths of its volume,

39、respectively. For thefourth lift, overfill the mold by mounding the concrete abovethe top of the mold.Again, place the tamping plate on the looseconcrete and consolidate. If the tamping plate consolidatesconcrete below the top level of the mold, turn off the vibratinghammer. Place additional concret

40、e in the mold so that, whenconsolidated, the concrete can be finished smooth and levelwith the top of the mold.FIG. 1 Vibrating Hammer for Molding RCC SpecimensC1435/C1435M 1438.3.8 Finally, strike off the top of the concrete with thevibrating hammer and tamping plate. With the hammer inoperation an

41、d the plate in contact with the rim of the cylindermold, move the plate back and forth across the top of thecylinder to force excess material beyond the rim. Continueworking the surface until it is smooth and level with the top ofthe cylinder mold. Avoid tearing the surface of the concrete.9. Keywor

42、ds9.1 compressive; consolidate; cylinder; molds; roller com-pacted concrete; soil cement; specimen; strength; tensile;vibrating hammerFIG. 2 Circular Steel Tamping Plate and Metal ShaftC1435/C1435M 144SUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this practice si

43、nce the last issue,C1435/C1435M 08, that may impact the use of this practice. (Approved October 1, 2014)(1) In Section 4, a note was added addressing the significanceof apparatus mass.(2) In 5.2, the allowable range of hammer mass was broadened.(3) In 5.3, the diameter of the tamping plate was incre

44、ased.(4) Revised Fig. 2.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringe

45、ment 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 reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard o

46、r for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views k

47、nown 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 A

48、STM 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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 145