1、Designation: D 5202 02Standard 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 o
3、f 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. Thist
4、est 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
5、of 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 valu
6、es 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
7、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 Documents2.1 ASTM Standards:D 422 Test Method for Particle-Size
8、Analysis of Soils2D 653 Terminology Relating to Soil, Rock, and ContainedFluids2D 854 Test Methods for Specific Gravity of Soil Solids byWater Pycnometer2D 2850 Test Method for Unconsolidated, Undrained Tri-axial Compression Test on Cohesive Soils2D 3740 Practice for Minimum Requirements for Agencie
9、sEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and Construction2D 4219 Test Method for Unconfined Compressive StrengthIndex of Chemical-Grouted Soils2D 4320 Test Method for Laboratory Preparation of Chemi-cally Grouted Soil Specimens for Obtaining DesignStren
10、gth Parameters2D 4767 Test Method for Consolidated Undrained TriaxialCompression Test for Cohesive Soils23. Terminology3.1 For common definitions of terms used in this testmethod, refer to Terminology D 653.3.2 Definitions of Terms Specific to This Standard:3.2.1 failurein creep studies, the stress
11、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 safety factors, based on engineering judg-ment must be determined by the user.NOTE 2Sampling procedures for in-
12、situ specimens have a majorinfluence on test results. Specimens 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 result
13、s. Speci-mens should be fabricated in accordance with Test Method 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 37
14、40 are generally considered capable of competentand objective 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
15、 some of those factors.1This test method is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.15 on Stabilization WithAdmixtures.Current edition approved Nov. 10, 2002. Published January 2003. Originallyapproved in 1991. Last previous e
16、dition approved in 1997 as D520291(1997).2Annual Book of ASTM Standards, Vol 04.08.1*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.5. Apparatus5.1 The requirements for
17、 equipment 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 prescri
18、bed 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
19、 load-measuring deviceshall be capable of measuring the axial load to an accuracy ofwithin 6 1 % 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 Compr
20、ession 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
21、applied 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
22、which 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 failur
23、e and 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 p
24、iston diameter of16the 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 6 0.25 psi (2 kPa) for pressures less than28 psi (200
25、kPa) and to within 6 1 % for pressures greater than28 psi (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 pressur
26、emeasuring 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 thes
27、pecimen 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 6 0.2 % of the initialspecimen height. The deformation indicator shall have a travelrange of at least 20 % of the initial height of the specimen a
28、ndmay 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 cir
29、cular 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 bas
30、e shall 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 ofth
31、e piston 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 toenc
32、ase the 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 poi
33、nt onthe 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 basewit
34、h rubber 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.
35、11 Specimen-Size Measurement DevicesDevices usedto determine the height and diameter of the specimen shallmeasure the respective dimensions to within 6 0.1 % of thetotal dimension and be constructed such that their use will notdisturb the specimen.NOTE 6Circumferential measuring tapes are recommende
36、d 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 Dev
37、iceThe specimen weighing deviceshall determine the mass of the specimen to an accuracy ofwithin 6 0.05 % of the total mass of the specimen.5.14 Testing EnvironmentPerform the test in an environ-ment where temperature fluctuations are less than 6 7.2F (64C) and there is no direct contact with sunligh
38、t.D52020225.15 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 c
39、ontent cans, 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 heigh
40、t-to-diameter 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).NO
41、TE 7If oversize 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 1
42、20 intervals. 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
43、 5.10).7.1.2 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
44、base with two rubber O-rings or otherpositive seal at each end. A thin 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. P
45、rocedure8.1 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 spe
46、cimen exceeding0.5 % 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 p
47、ressure 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 axial load. Prior to axial load
48、ing andthe initiation of shear, perform the following steps:8.2.1 Place the chamber in position in the axial loadingdevice. Be careful to align the axial loading device, the axialload-measuring device, and the triaxial chamber to prevent theapplication of a lateral force to the piston during shear.8
49、.2.2 During this procedure, care should be taken not toapply an axial load to the specimen exceeding 0.5 % of theestimated axial load at failure. If the axial load-measuringdevice is located outside of the triaxial chamber, the chamberpressure will produce an upward force on the piston that willreact against the axial loading device. In this case, start shearwith the piston slightly above the specimen cap, and before thepiston comes in contact with the specimen cap, either measureand record the initial piston friction and upward thrust of thepiston produc
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