1、Designation: D3689/D3689M 07 (Reapproved 2013)1Standard Test Methods forDeep Foundations Under Static Axial Tensile Load1This standard is issued under the fixed designation D3689/D3689M; the number immediately following the designation indicates theyear of original adoption or, in the case of revisi
2、on, 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.1NOTEDesignation was editorially corrected to match units information in June 2013.1. Scope1.1 The test methods de
3、scribed in this standard measure theaxial deflection of a vertical or inclined deep foundation whenloaded in static axial tension. These methods apply to all deepfoundations, referred to herein as “piles,” that function in amanner similar to driven piles or cast in place piles, regardlessof their me
4、thod of installation, and may be used for testingsingle piles or pile groups. The test results may not representthe long-term performance of a deep foundation.1.2 This standard provides minimum requirements for test-ing deep foundations under static axial tensile load. Plans,specifications, provisio
5、ns, or any combination thereof preparedby a qualified engineer may provide additional requirementsand procedures as needed to satisfy the objectives of aparticular test program. The engineer in responsible charge ofthe foundation design, referred to herein as the engineer, shallapprove any deviation
6、s, deletions, or additions to the require-ments of this standard.1.3 This standard allows the following test procedures:Procedure Test SectionA Quick Test 8.1.2B Maintained Test (optional) 8.1.3C Loading in Excess of Maintained Test (optional) 8.1.4D Constant Time Interval Test (optional) 8.1.5E Con
7、stant Rate of Uplift Test (optional) 8.1.6F Cyclic Loading Test (optional) 8.1.71.4 Apparatus and procedures herein designated “optional”may produce different test results and may be used only whenapproved by the engineer. The word “shall” indicates amandatory provision, and the word “should” indica
8、tes arecommended or advisory provision. Imperative sentencesindicate mandatory provisions.1.5 A qualified geotechnical engineer should interpret thetest results obtained from the procedures of this standard so asto predict the actual performance and adequacy of piles used inthe constructed foundatio
9、n. See Appendix X1 for commentsregarding some of the factors influencing the interpretation oftest results.1.6 A qualified engineer shall design and approve all load-ing apparatus, loaded members, support frames, and testprocedures. The text of this standard references notes andfootnotes which provi
10、de explanatory material. These notes andfootnotes (excluding those in tables and figures) shall not beconsidered requirements of the standard. This standard alsoincludes illustrations and appendices intended only for ex-planatory or advisory use.1.7 The values stated in either SI units or inch-pound
11、 unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.8 The gravitational system of inch-poun
12、d units is usedwhen dealing with inch-pound units. In this system, the poundlbf represents a unit of force weight, while the unit for massis slugs. The rationalized slug unit is not given, unless dynamicF=ma calculations are involved.1.9 All observed and calculated values shall conform to theguideli
13、nes for significant digits and rounding established inPractice D6026.1.10 The method used to specify how data are collected,calculated, or recorded in this standard is not directly related tothe accuracy to which the data can be applied in design or otheruses, or both. How one applies the results ob
14、tained using thisstandard is beyond its scope.1.11 ASTM International takes no position respecting thevalidity of any patent rights asserted in connection with anyitem mentioned in this standard. Users of this standard areexpressly advised that determination of the validity of any such1These test me
15、thods are under the jurisdiction ofASTM Committee D18 on Soiland Rock and are the direct responsibility of Subcommittee D18.11 on DeepFoundations.Current edition approved June 15, 2013. Published July 2013. Originallyapproved in 1978. Last previous edition approved in 2007 as D3689 07. DOI:10.1520/D
16、3689_D3689M-07R13.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1patent rights, and the risk of infringement of such rights, areentirely their own responsibility.1.12 This standard does not purport to address all of thesafety concern
17、s, 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:2D653 Terminology Relating to Soil, Rock, a
18、nd ContainedFluidsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD5882 Test Method for Low Strain Impact Integrity Testingof Deep FoundationsD6026 Practice for Using Significant Digits in Geotechn
19、icalDataD6760 Test Method for Integrity Testing of Concrete DeepFoundations by Ultrasonic Crosshole Testing2.2 American National Standards:ASME B30.1 Jacks3ASME B40.100 Pressure Gages and Gauge Attachments3ASME B89.1.10.M Dial Indicators (For Linear Measure-ments)33. Terminology3.1 DefinitionsFor co
20、mmon definitions of terms used inthis standard see Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 cast in-place pile, na deep foundation unit made ofcement grout or concrete and constructed in its final location,e.g. drilled shafts, bored piles, caissons, auger cast piles,
21、pressure-injected footings, etc.3.2.2 deep foundation, na relatively slender structuralelement that transmits some or all of the load it supports to soilor rock well below the ground surface, such as a steel pipe pileor concrete drilled shaft.3.2.3 driven pile, na deep foundation unit made of pre-fo
22、rmed material with a predetermined shape and size andtypically installed by impact hammering, vibrating, or pushing.3.2.4 failure load, nfor the purpose of terminating anaxial tensile load test, the test load at which continuing,progressive movement occurs, or at which the total axialmovement exceed
23、s 15 % of the pile diameter or width, or asspecified by the engineer.3.2.5 telltale rod, nan unstrained metal rod extendedthrough the test pile from a specific point to be used as areference from which to measure the change in the length ofthe loaded pile.3.2.6 wireline, na steel wire mounted with a
24、 constanttension force between two supports and used as a reference lineto read a scale indicating movement of the test pile.4. Significance and Use4.1 Field tests provide the most reliable relationship be-tween the axial load applied to a deep foundation and theresulting axial movement. Test result
25、s may also provideinformation used to assess the distribution of side shearresistance along the pile shaft and the long-term load-deflectionbehavior.Afoundation designer may evaluate the test results todetermine if, after applying an appropriate factor of safety, thepile or pile group has an ultimat
26、e static capacity and adeflection at service load satisfactory to support a specificfoundation. When performed as part of a multiple-pile testprogram, the designer may also use the results to assess theviability of different piling types and the variability of the testsite.4.2 If feasible, without e
27、xceeding the safe structural load onthe pile(s) or pile cap, the maximum load applied should reacha failure load from which the engineer may determine theultimate axial static tensile load capacity of the pile(s). Teststhat achieve a failure load may help the designer improve theefficiency of the fo
28、undation by reducing the piling length,quantity, or size.4.3 If deemed impractical to apply axial test loads to aninclined pile, the engineer may elect to use axial test resultsfrom a nearby vertical pile to evaluate the axial capacity of theinclined pile.NOTE 1The quality of the result produced by
29、these test methods isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies that meet thecriteria of Practice D3740 are generally considered capable of competentand objective testing/sampling/inspection/etc. Users of these test m
30、ethodsare cautioned that compliance with Practice D3740 does not in itselfassure reliable results. Reliable results depend on many factors; PracticeD3740 provides a means of evaluating some of those factors.5. Test Foundation Preparation5.1 Excavate or add fill to the ground surface around the testp
31、ile or pile group to the final design elevation unless otherwiseapproved by the engineer.5.2 Design and construct the test pile(s) so that any locationalong the depth of the pile will safely sustain the maximumanticipated axial compressive and tensile load to be developedat that location. Cut off or
32、 build up the test pile(s) as necessaryto permit construction of the load-application apparatus, place-ment of the necessary testing and instrumentation equipment,and observation of the instrumentation. Remove any damagedor unsound material from the pile top as necessary to properlyinstall the appar
33、atus for measuring movement, for applyingload, and for measuring load.5.3 For tests on pile groups, cap the pile group withsteel-reinforced concrete or a steel load frame designed tosafely sustain the anticipated loads.5.4 Install structural tension connectors extending from thetest pile or pile cap
34、, constructed of steel straps, bars, cables,and/or other devices bolted, welded, cast into, or otherwise2For 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 standard
35、s Document Summary page onthe ASTM website.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.D3689/D3689M 07 (2013)12firmly affixed to the test pile or pile cap to safely apply themaximum requ
36、ired tensile test load without slippage, rupture,or excessive elongation. Carefully inspect these tension mem-bers for any damage that may reduce their tensile capacity.Tension members with a cross-sectional area reduced bycorrosion or damage, or material properties compromised byfatigue, bending, o
37、r excessive heat, may rupture suddenlyunder load. Do not use brittle materials for tension connections.NOTE 2Deep foundations sometimes include hidden defects that maygo unnoticed prior to static testing. Low strain integrity tests as describedin Test Method D5882 and ultrasonic crosshole integrity
38、tests as describedin Test Method D6760 may provide a useful pre-test evaluation of the testfoundation.6. Apparatus for Applying and Measuring Loads6.1 General:6.1.1 The apparatus for applying tensile loads to a test pileor pile group shall conform to one of the methods described in6.3-6.6. The metho
39、d in 6.3 is recommended. The method in 6.5can develop high tensile loads with relatively low jackingcapacity, but does not perform well for tests to failure or forlarge upward movements.6.1.2 Reaction piles, if used, shall be of sufficient numberand installed so as to safely provide adequate reactio
40、n capacitywithout excessive movement. When using two or more reac-tion piles at each end of the test beam(s), cap them withreaction beams (Fig. 1). Locate reaction piles so that resultanttest beam load supported by them acts at the center of thereaction pile group. Cribbing, if used as a reaction, s
41、hall be ofsufficient plan dimensions to transfer the reaction loads to thesoil without settling at a rate that would prevent maintainingthe applied loads.6.1.3 Cut off or build up reaction piles as necessary to placethe reaction or test beam(s). Remove any damaged or unsoundmaterial from the top of
42、the reaction piles, and provide asmooth bearing surface parallel to the reaction or test beam(s).To minimize stress concentrations due to minor surfaceirregularities, set steel bearing plates on the top of precast orcast-in-place concrete reaction piles in a thin layer of quick-setting, non-shrink g
43、rout, less than 6 mm 0.25 in. thick andhaving a compressive strength greater than the reaction pile atthe time of the test. For steel reaction piles, weld a bearingplate to each pile, or weld the cap or test beam(s) directly toeach pile. For timber reaction piles, set the bearing plate(s)directly on
44、 the cleanly cut top of the pile, or in grout asdescribed for concrete piles.6.1.4 Provide a clear distance between the test pile(s) andthe reaction piles or cribbing of at least five times themaximum diameter of the largest test or reaction pile(s), butnot less than 2.5 m 8 ft. The engineer may inc
45、rease ordecrease this minimum clear distance based on factors such asthe type and depth of reaction, soil conditions, and magnitudeof loads so that reaction forces do not significantly effect thetest results.NOTE 3Excessive vibrations during reaction pile installation innon-cohesive soils may affect
46、 test results. Reaction piles that penetratedeeper than the test pile may affect test results. Install the anchor pilesnearest the test pile first to help reduce installation effects.6.1.5 Each jack shall include a lubricated hemisphericalbearing or similar device to minimize lateral loading of the
47、pileor pile group. The hemispherical bearing(s) should include alocking mechanism for safe handling and setup.6.1.6 Provide bearing stiffeners as needed between theflanges of test and reaction beams.6.1.7 Provide steel bearing plates to spread the load to andbetween the jack(s), load cell(s), hemisp
48、herical bearing(s), testbeam(s), reaction beam(s), and reaction pile(s). Unless other-wise specified by the engineer, the size of the bearing platesshall be not less than the outer perimeter of the jack(s), loadcell(s), or hemispherical bearing(s), nor less than the totalwidth of the test beam(s), r
49、eaction beam(s), reaction piles so asto provide full bearing and distribution of the load. Bearingplates supporting the jack(s), test beam(s), or reaction beamson timber or concrete cribbing shall have an area adequate forsafe bearing on the cribbing.6.1.8 Unless otherwise specified, where using steel bearingplates, provide a total plate thickness adequate to spread thebearing load between the outer perimeters of loaded surfaces ata maximum angle of 45 degrees to the loaded axis. For centerhole jacks and center hole load cells, also provide steel platesadequ
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