1、Designation: D 5202 08Standard Test Method forDetermining Triaxial Compression Creep Strength ofChemical Grouted Soils1This standard is issued under the fixed designation D 5202; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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 long-termstrength and deformation of a cylindrical specimen of
3、either a(undisturbed) field sample or laboratory-fabricated chemicalgrouted soil when it is sheared undrained in compression undera constant sustained load.NOTE 1The voids of chemical grouted soils are most often substan-tially filled with grout. Thus, pore pressures are unlikely to develop. Thistes
4、t method is not applicable to partially grouted soils in which substantialpore pressures may develop. If pore pressures must be measured,reference is made to Test Method D 4767 for equipment and procedures.1.2 This test method provides data useful in determiningstrength and deformation properties of
5、 chemical grouted soilssubjected to sustained loads. Mohr strength envelopes may alsobe determined.1.3 The determination of strength envelopes and the devel-opment of relationships to aid in interpreting and evaluatingtest results are left to the engineer or office requesting the test.1.4 The values
6、 stated in either SI or inch-pound units shallbe regarded separately as standard. The values in each systemmay not be exact equivalents, therefore, each system must beused independently of the other, without combining values inany way.1.5 This standard does not purport to address all of thesafety co
7、ncerns, 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.1.6 This test method offers a set of instructions for perform-ing one or more sp
8、ecific operations. This document cannotreplace education or experience and should be used in con-junction with professional judgment. Not all aspects of thispractice may be applicable in all circumstances. This ASTMstandard is not intended to represent or replace the standard ofcare by which the ade
9、quacy of a given professional servicemust be judged, nor should this document be applied withoutconsideration of a projects many unique aspects. The word“Standard” in the title of this document means only that thedocument has been approved through the ASTM consensusprocess.2. Referenced Documents2.1
10、 ASTM Standards:2D 422 Test Method for Particle-Size Analysis of SoilsD 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 854 Test Methods for Specific Gravity of Soil Solids byWater PycnometerD 2850 Test Method for Unconsolidated-Undrained Tri-axial Compression Test on Cohesive SoilsD 37
11、40 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and ConstructionD 4219 Test Method for Unconfined Compressive StrengthIndex of Chemical- Grouted SoilsD 4320 Practice for Laboratory Preparation of ChemicallyGroute
12、d Soil Specimens for Obtaining Design StrengthParametersD 4767 Test Method for Consolidated Undrained TriaxialCompression Test for Cohesive SoilsD 6026 Practice for Using Significant Digits in Geotechni-cal Data3. Terminology3.1 For common definitions of terms used in this testmethod, refer to Termi
13、nology D 653.3.2 Definitions of Terms Specific to This Standard:3.2.1 failurein creep studies, the stress condition at ex-cessive (15 to 20 %) strain, or at continuing strain leading tofracture.4. Significance and Use4.1 Data from these tests may be used for structural designpurposes. Adequate safet
14、y factors, based on engineering judg-ment must be determined by the user.1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.15 on Stabilization WithAdmixtures.Current edition approved Jan. 1, 2008. Published February
15、2008. Originallyapproved in 1991. Last previous edition approved in 2002 as D 5202 02.2For 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 standards Document Summary
16、 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 Conshohocken, PA 19428-2959, United States.NOTE 2Sampling procedures for in-situ specimens have a majorinfluence on test results. Specime
17、ns carefully trimmed in the laboratoryfrom large block samples taken in the field have the least chance offracturing prior to testing. Sample preparation methods of laboratory-fabricated specimens also have a major influence on test results. Speci-mens should be fabricated in accordance with Test Me
18、thod D 4320.NOTE 3The quality of the result produced by this test method isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies that meet thecriteria of Practice D 3740 are generally considered capable of competentand objective
19、 testing/sampling/inspection/etc. Users of this test methodare cautioned that compliance with Practice D 3740 does not in itselfassure reliable results. Reliable results depend on many factors; PracticeD 3740 provides a means of evaluating some of those factors.5. Apparatus5.1 The requirements for e
20、quipment needed to performsatisfactory tests are given in the following sections:5.2 Axial Loading DeviceThe axial compression devicemay be a dead weight system, a pneumatic or hydraulic loadcell, or any other device capable of applying and maintainingdesired constant loads to the accuracy prescribe
21、d for the load-measuring device.5.3 Axial Load-Measuring DeviceThe axial load-measuring device may be a load ring, electronic load cell,hydraulic load cell, or any other load-measuring device capableof the accuracy prescribed in this subsection and may be partof the axial loading device. The axial l
22、oad-measuring deviceshall be capable of measuring the axial load to an accuracy ofwithin 61 % of the axial load at failure. If the load-measuringdevice is located inside the triaxial chamber it shall beinsensitive to horizontal forces and to the magnitude of thechamber pressure.5.4 Triaxial Compress
23、ion ChamberThe triaxial chambershall consist of a headplate and a baseplate separated by acylinder. The size of the cylinder should be enough to yield aminimum annular clearance of12 in. (12 mm) with the untestedspecimen. The cylinder may be constructed of any materialcapable of withstanding the app
24、lied pressures. It is desirable touse a transparent material or have a cylinder provided withviewing ports so the behavior of the specimen may beobserved. The headplate shall have a vent valve such that aircan be forced out of the chamber as it is filled. The baseplateshall have an inlet through whi
25、ch the pressure liquid is suppliedto the chamber, and appropriate connections for the specimenbase.5.5 Axial Load PistonThe piston passing through the topof the chamber and its seal must be designed so the variationin the axial load due to friction does not exceed 0.1 % of theaxial load at failure a
26、nd so there is negligible lateral bending ofthe piston during loading. Alternatively, the apparatus may becalibrated, and a correction for friction may be made.NOTE 4The use of two linear ball bushings to guide the piston isrecommended to minimize friction and maintain alignment.NOTE 5A minimum pist
27、on diameter of16 the specimen diameter hasbeen used successfully in many laboratories to minimize lateral bending.5.6 Pressure Control DevicesThe chamber pressure con-trol devices shall be capable of applying and controllingpressures to within 60.25 psi (2 kPa) for pressures less than 28psi (200 kPa
28、) and to within 61 % for pressures greater than 28psi (200 kPa). The device may consist of self -compensatingmercury pots, pneumatic pressure regulators, or any otherdevice capable of applying and controlling pressures to therequired tolerances.5.7 Pressure-Measurement DevicesThe chamber pressuremea
29、suring devices shall be capable of measuring pressures tothe tolerances given in 5.6. They may consist of Bourdongages, pressures manometers, electronic pressure transducers,or any other device capable of measuring to the statedtolerances.5.8 Deformation IndicatorThe vertical deformation of thespeci
30、men is usually determined from the travel of the pistonacting on top of the specimen. The piston travel shall bemeasured with an accuracy of at least 60.2 % of the initialspecimen height. The deformation indicator shall have a travelrange of at least 20 % of the initial height of the specimen andmay
31、 be a dial indicator, linear variable differential transformer(LVDT), extensometer, or other measuring device meeting therequirements for accuracy and range.5.9 Specimen Cap and BaseThe specimen cap and baseshall be constructed of a rigid, noncorrosive, impermeablematerial, and shall have a circular
32、 plane surface of contact withthe specimen and a circular cross section. The weight of thespecimen cap shall be less than 0.5 % of the applied axial loadat failure or less than 0.1 lb (50 g). The diameter of the cap andbase shall be equal to the initial diameter of the specimen. Thespecimen base sha
33、ll be connected to the triaxial compressionchamber to prevent lateral motion or tilting, and the specimencap shall be designed to receive the piston such that eccentric-ity of the piston-to-cap contact relative to the vertical axis ofthe specimen does not exceed 0.05 in. (0.13 cm). The end ofthe pis
34、ton and specimen cap contact area shall be designed sothat tilting of the specimen cap during the test is minimal. Thecylindrical surface of the specimen base and cap that contactsthe membrane to form a seal shall be smooth and free ofscratches.5.10 Rubber MembraneThe rubber membrane used toencase t
35、he specimen shall provide reliable protection againstleakage. To check a membrane for leakage, the membrane shallbe placed around a cylindrical form, sealed at both ends withrubber O-rings, subjected to a small air pressure on the inside,and immersed in water. If air bubbles appear from any point on
36、the membrane, it shall be rejected. To offer minimum restraintto the specimen, the unstretched membranes diameter shall bebetween 90 and 95 % of that specimen. The membranethickness shall not exceed 1 % of the diameter of the specimen.The membrane shall be sealed to the specimen cap and basewith rub
37、ber O-rings with an unstressed inside diameter be-tween 75 and 85 % of the diameter of the cap and base, or byother means that will provide a positive seal. An equation forcorrecting deviator stress (principal stress difference) for theeffect of the stiffness of the membrane is given in 10.3.5.11 Sp
38、ecimen-Size Measurement DevicesDevices usedto determine the height and diameter of the specimen shallmeasure the respective dimensions to within 60.1 % of thetotal dimension and be constructed such that their use will notdisturb the specimen.D5202082NOTE 6Circumferential measuring tapes are recommen
39、ded over cali-pers for measuring the diameter.5.12 RecordersSpecimen behavior may be recordedmanually or by electronic digital or analog recorders. Ifelectronic recorders are used, it shall be necessary to calibratethe measuring devices through the recorder using known inputstandards.5.13 Weighing D
40、eviceThe specimen weighing deviceshall determine the mass of the specimen to an accuracy ofwithin 60.05 % of the total mass of the specimen.5.14 Testing EnvironmentPerform the test in an environ-ment where temperature fluctuations are less than 67.2F(64C) and there is no direct contact with sunlight
41、.5.15 Miscellaneous ApparatusSpecimen trimming andcarving tools including a wire saw, steel straightedge, miterbox and vertical trimming lath, may be needed for fieldsamples. Apparatus for preparing laboratory specimens isdetailed in Test Method D 4320. Membranes and O-ringexpander, water content ca
42、ns, and data sheets shall be providedas required.6. Test Specimen Preparation6.1 Fabricate specimens as described in Test MethodD 4320, or carefully trim from samples taken in the field.6.2 Specimen SizeSpecimens shall be cylindrical andhave a minimum diameter of 1.3 in. (3.3 cm). The height-to-diam
43、eter ratio shall be between 2.5 and 3.0. The largest particlesize shall be smaller than16 the specimen diameter. If, aftercompletion of a test, it is found based on visual observationthat oversize particles are present, indicate this information inthe report of test data (see Section 11).NOTE 7If ov
44、ersize particles are found in the specimen after testing, aparticle-size analysis performed in accordance with Method D 422 may beperformed to confirm the visual observation and the results provided withthe test report (see Section 11).6.3 Specimen MeasurementMeasure height of specimensat 120 interv
45、als. Diameter shall be measured at three places.Immediately record weight after trimming of fabrication.7. Specimen Mounting7.1 PreparationsBefore mounting the specimen in thetriaxial chamber, make the following preparations:7.1.1 If deemed necessary, check the rubber membrane forleaks (see 5.10).7.
46、1.2 Place the membrane on the membrane expander or, ifit is to be rolled onto the specimen, roll the membrane on thecap or base.7.1.3 Attach the pressure-control and pressure measurementsystem to the chamber base.7.1.4 Place the rubber membrane around the specimen andseal it at the cap and base with
47、 two rubber O-rings or otherpositive seal at each end.Athin coating of silicon grease on thevertical surfaces of the cap and base will aid in sealing themembrane.7.1.5 Check the alignment of the specimen and the speci-men cap. If there is any eccentricity, realign the specimen andcap.8. Procedure8.1
48、 After assembling the triaxial chamber, perform thefollowing operations:8.1.1 Bring the axial load piston into contact with thespecimen cap several times to permit proper seating andalignment of the piston with the cap. During this procedure,take care not to apply an axial load to the specimen excee
49、ding0.5 % of the estimated axial load at failure. When the piston isbrought into contact with the cap the final time, record thereading on the deformation indicator and lock the piston inplace.8.1.2 Fill the chamber with the chamber fluid, and apply thechamber pressure.NOTE 8The chamber pressure for any one series of tests should be afixed percentage of the applied axial stress. The actual value used may beselected from anticipated lateral pressure relationships in the field.8.2 ShearDuring shear, keep constant both the chamberpressure and the applied
