1、Designation: D 1635 00 (Reapproved 2006)Standard Test Method forFlexural Strength of Soil-Cement Using Simple Beam withThird-Point Loading1This standard is issued under the fixed designation D 1635; the number immediately following the designation indicates the year oforiginal adoption or, in the ca
2、se 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. Scope*1.1 This test method covers the determination of the flexuralstrength of soil-cement by the
3、use of a simple beam withthird-point loading.NOTE 1For methods of molding soil-cement specimens, see PracticeD 1632.1.2 UnitsThe values stated in SI units are to be regardedas standard. The values given in parentheses are mathematicalconversions to inch-pound units, which are provided forinformation
4、 only and are not considered standard.1.2.1 The converted inch-pound units use the gravitationalsystem of units. In this system, the pound (lbf) represents a unitof force (weight), while the unit for mass is slugs. Theconverted slug unit is not given, unless dynamic (F = ma)calculations are involved
5、.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.2. Referenced
6、Documents2.1 ASTM Standards:2D 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 1632 Practice for Making and Curing Soil-Cement Com-pression and Flexure Test Specimens in the Laboratory3D 3740 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil
7、and Rockas Used in Engineering Design and ConstructionE4 Practices for Force Verification of Testing Machines3. Terminology3.1 Definitions:3.1.1 For common definitions of terms in this standard, referto Terminology D 653.4. Significance and Use4.1 This test method is used to determine the flexuralst
8、rength of soil-cement. Flexural strength is significant inpavement design and is used to determine slab thickness.NOTE 2The quality of the result produced by this standard isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies
9、that meet thecriteria of Practice D 3740 are generally considered capable of competentand objective testing/sampling/inspection/etc. Users of this standard arecautioned that compliance with Practice D 3740 does not in itself assurereliable results. Reliable results depend on many factors; Practice D
10、 3740provides a means of evaluating some of those factors.5. Apparatus5.1 Testing MachineThe testing machine may be of anytype having sufficient capacity and control to provide the rateof loading (prescribed in 7.2). It shall conform to the require-ments of Section 15 of Practices E4. The testing ma
11、chine shallbe equipped with a spherically seated head block having abearing surface of at least 75 % of the width of the beam butnot greatly in excess of the width of the beam. The movable1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibilit
12、y of Subcommittee D18.15 on Stabilization byAdmixtures.Current edition approved May 1, 2006. Published June 2006. Originallyapproved in 1959. Last previous edition approved in 2000 as D 1635 00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at s
13、erviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1
14、9428-2959, United States.portion of this block shall be held closely in the spherical seat,but the design shall be such that the bearing face may berotated freely and tilted through small angles in any direction.5.2 The third-point loading method used in making flexuretests of soil-cement shall empl
15、oy bearing blocks that willensure that forces applied to the beam will be vertical only andapplied without eccentricity. A diagrammatic drawing of anapparatus that accomplishes this purpose is shown in Fig. 1.The apparatus shall be designed to incorporate the followingprinciples:5.2.1 The distance b
16、etween supports and points of loadapplication shall remain constant for a given apparatus.5.2.2 The direction of the reactions shall be parallel to thedirection of the applied load at all times during the test.5.2.3 The load shall be applied at a uniform rate and in sucha manner as to avoid shock.5.
17、2.4 The directions of loads and reactions may be main-tained parallel by judicious use of linkages, rocker bearings,and flexure plates. Eccentricity of loading can be avoided byuse of spherical bearings.6. Test Specimens6.1 The standard test specimens shall be beams 76 by 76 by290 mm (3 by 3 by 1114
18、 in.), but a similar test method may beused for testing specimens of other sizes. Test the specimens ontheir sides with respect to their molded position.6.2 Make flexural tests of moist cured specimens as soon aspracticable after removing them from the moist room, andduring the period between remova
19、l from the moist room andtesting keep the specimens moist by a wet burlap or blanketcovering.NOTE 3Other conditioning procedures, such as soaking in water, airor oven drying, alternate wetting and drying or alternate freezing andthawing, may be specified after an initial moist curing period. Curing
20、andconditioning procedures shall be given in detail in the report.6.3 Check the smoothness of the side faces of the beams atthe points where loads will be applied with a straightedge. Ifnecessary, cap the faces to meet the requirements of Section 15of Practice D 1632.7. Procedure7.1 Turn the specime
21、n on its side with respect to its moldedposition and center it on the lower half-round steel supports,which have been spaced apart a distance of three times thedepth of the beam. Place the load-applying block assembly incontact with the upper surface of the beam at the third pointsbetween the suppor
22、ts. Carefully align the center of the beamwith the center of thrust of the spherically seated head block ofthe machine. As this block is brought to bear on the beam-loading assembly, rotate its movable portion gently by hand sothat uniform seating is obtained.7.2 Apply the load continuously and with
23、out shock.Ascrewpower testing machine, with the moving head operating atapproximately 0.02 mm/s (0.05 in./min) when the machine isrunning idle, may be used. With hydraulic machines adjust theloading to such a constant rate that the extreme fiber stress iswithin the limits of 690 6 39 kPa/min (100 6
24、5 psi). Recordthe total load of failure of the specimen to the nearest 40 N (10lbf).8. Measurement of Specimens After Test8.1 Make measurements to the nearest 0.25 mm (0.01 in.) todetermine the average width and depth of the specimens at thesection of failure.9. Calculations9.1 If the fracture occur
25、s within the middle third of the spanlength, calculate the modulus of rupture as follows:R 5 PL/bd2where:R = modulus of rupture, kPa (psi),P = maximum applied load, N (lbf),l = span length, mm (in.),b = average width of specimen, mm (in.), andd = average depth of specimen, mm (in.).NOTE 4Mass of the
26、 beam is not included in the above calculation.9.2 If the fracture occurs outside the middle third of the spanlength by not more than 5 % of the span length, calculate themodulus of rupture as follows:FIG. 1 Diagrammatic View of Apparatus for Flexure Test of Soil-Cement by Third-Point Loading Method
27、D 1635 00 (2006)2R 5 3Pa/bd2where:a = distance between line of fracture and the nearestsupport, measured along the center line of the bottomsurface of the beam.9.3 If the fracture occurs outside the middle third of the spanby more than 5 % of the span length, discard the results of thetest.10. Repor
28、t10.1 The report shall include the following:10.1.1 Specimen identification number,10.1.2 Average width and depth at section of failure to thenearest 0.25 mm (0.01 in.),10.1.3 Maximum load, to the nearest 40 N (10 lbf),10.1.4 Modulus of rupture, calculated to the nearest 35 kPa(5 psi),10.1.5 Defects
29、, if any, in specimen,10.1.6 Age of specimen, and10.1.7 Details of curing and conditioning periods, and watercontent at time of test.11. Precision and Bias11.1 PrecisionThe precision of this test method has notbeen established by an interlaboratory test program. However,based on test data that are a
30、vailable, the following may serve asa guide to the variability of flexural strength test results.11.1.1 Tests were performed in a single lab on a silt loamsoil with 92 % passing the No. 200 sieve. Liquid limit andplasticity index of soil were 26 and 7, respectively. The seriesof tests consisted of 2
31、4 specimens, 12 at 6 % cement, 12 at14 % cement. The specimens were cured in a moist room at23C (73 F) for 28 days. Results4of the tests are given inTable 1.11.2 BiasThere is no accepted reference value for this testmethod, therefore, bias cannot be determined.12. Keywords12.1 flexural strength; soi
32、l-cement; soil stabilizationSUMMARY OF CHANGESIn accordance with Committee D18 policy, this section identifies the location of changes to this standard sincethe last edition (95) that may impact the use of the standard.(1) Section 1 Inserted as 1.2 statement on units andrenumbered section 1.2 to 1.3
33、.(2) Section 2.1 Inserted references to D 653 and D 3740.(3) Section 2.1 Updated title of E4reference.(4) New section 3 Inserted new section 3 Terminologywith reference to D 653 for terms. Renumbered subsequentsections as needed.(5) Renumbered section 4 Inserted as Note 2 standardreference to D 3740
34、 and renumbered remaining notes asneeded.(6) Renumbered sections 6.1, 7.2, 8.1, 9.1, 10.1.2, 10.1.3,10.1.4, and 11.1.1 and Fig. 1 placed SI units first and placesinch-pound units in parentheses.(7) Added Summary of Changes section.(8) Corrected headquarters address for ASTMASTM International takes n
35、o 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 infringement of such rights, are entirely their own respon
36、sibility.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 or for additional standardsand should be addressed
37、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 known to the ASTM Committee on Standards, at the ad
38、dress 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)
39、, 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).4Felt, E. J., Abrams, M. S., Strength and Elastic Properties of CompactedSoil-Cement Mixtures, ASTM STP 206, ASTM, 1957.TABLE 1 PrecisionAverage flexuralstrength, psiStandarddeviation,psiCoefficient ofvariation, %Specimens with 6 % cement 94 6 6.4Specimens with 14 % cement 157 9 5.7D 1635 00 (2006)3
