ASTM D1143 D1143M-2007 Standard Test Methods for Deep Foundations Under Static Axial Compressive Load.pdf

1、Designation: D 1143/D 1143M 07Standard Test Methods forDeep Foundations Under Static Axial Compressive Load1This standard is issued under the fixed designation D 1143/D 1143M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the yea

2、r of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 The test methods described in

3、this standard measure theaxial deflection of a vertical or inclined deep foundation whenloaded in static axial compression. These methods apply to alldeep foundations, referred to herein as piles, that function in amanner similar to driven piles or castinplace piles, regardlessof their method of ins

4、tallation, 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 compressive load.Plans, specifications, and/or provisio

5、ns prepared by a qualifiedengineer may provide additional requirements and proceduresas needed to satisfy the objectives of a particular test program.The engineer in responsible charge of the foundation design,referred to herein as the Engineer, shall approve any devia-tions, deletions, or additions

6、 to the requirements of thisstandard.1.3 This standard allows the following test procedures:Procedure A Quick TestProcedure B Maintained Test (optional)Procedure C Loading in Excess of Maintained Test (optional)Procedure D Constant Time Interval Test (optional)Procedure E Constant Rate of Penetratio

7、n Test (optional)Procedure F Constant Movement Increment Test (optional)Procedure G Cyclic Loading Test (optional)1.4 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 provi

8、sion, and the word “should” indicates 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 pile

9、s used inthe constructed foundation. 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 referen

10、ces notes andfootnotes which provide explanatory material. These notes andfootnotes (excluding those in tables and figures) shall not beconsidered as requirements of the standard. This standard alsoincludes illustrations and appendices intended only for ex-planatory or advisory use.1.7 The values st

11、ated in either SI units or inch-pound 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

12、The gravitational system of inch-pound units is usedwhen dealing with inch-pound units. In this system, the pound(lbf) represents a unit of force (weight), while the unit for massis slugs. The rationalized slug unit is not given, unless dynamic(F=ma) calculations are involved.1.9 All observed and ca

13、lculated values shall conform to theguidelines for significant digits and rounding established inPractice D 6026.1.10 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 otheru

14、ses, or both. How one applies the results obtained using thisstandard is beyond its scope.1.11 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 practi

15、ces and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 3740 Practice for Minimum Requirements for Agencies1This test method is under the jurisdiction ofASTM Committee D18 on

16、 Soil andRock and is the direct responsibility of Subcommittee D18.11 on Deep Foundations.Current edition approved Feb. 1, 2007. Published April 2007. Originallyapproved in 1950. Discontinued in August 1995 and reinstated in 2007 asD 114307. Last previous edition approved in 1994 as D 1143 81(1994)e

17、1.2For 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 page onthe ASTM website.1*A Summary of Changes section appears at the end of this s

18、tandard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Engaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and ConstructionD 5882 Test Method for Low Strain Integrity Testing ofPilesD 6026 Practice

19、for Using Significant Digits in Geotechni-cal DataD 6760 Test Method for Integrity Testing of Concrete DeepFoundations by Ultrasonic Crosshole Testing2.2 American National Standards:3ASME B30.1 JacksASME B40.100 Pressure Gages and Gauge AttachmentsASME B89.1.10.M Dial Indicators (For Linear Measure-

20、ments)3. Terminology3.1 For common definitions of terms used in this standardsee Terminology D 653 Terminology Relating to Soil, Rock,and Contained Fluids.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 construc

21、ted in its final location,for example, drilled shafts, bored piles, caissons, auger castpiles, pressure-injected footings, etc3.2.2 deep foundation, n a relatively slender structuralelement that transmits some or all of the load it supports to soilor rock well below the ground surface, such as a ste

22、el pipe pileor concrete drilled shaft3.2.3 driven pile, na deep foundation unit made of pre-formed 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 compressive load test, the tes

23、t load at which rapidcontinuing, progressive movement occurs, or at which the totalaxial movement exceeds 15 % of the pile diameter or width, oras specified 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

24、which to measure the change in the length ofthe loaded pile.3.2.6 wireline, na steel wire mounted with a 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 relati

25、onship be-tween the axial load applied to a deep foundation and theresulting axial movement. Test results may also provideinformation used to assess the distribution of side shearresistance along the pile shaft, the amount of end bearingdeveloped at the pile toe, and the long-term load-deflectionbeh

26、avior.Afoundation designer may evaluate the test results todetermine if, after applying an appropriate factor of safety, thepile or pile group has an ultimate static capacity and adeflection at service load satisfactory to support a specificfoundation. When performed as part of a multiple-pile testp

27、rogram, 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 exceeding the safe structural load onthe pile(s) or pile cap, the maximum load applied should reacha failure load from which the Engineer may de

28、termine theultimate axial static compressive load capacity of the pile(s).Tests that achieve a failure load may help the designer improvethe efficiency of the foundation by reducing the piling length,quantity, or size.4.3 If deemed impractical to apply axial test loads to aninclined pile, the Engine

29、er 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 this test method isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Age

30、ncies that meet thecriteria of Practice D 3740 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;

31、PracticeD 3740 provides a means of evaluating some of those factors.5. Test Foundation Preparation5.1 Excavate or add fill to the ground surface around the testpile or pile group to the final design elevation unless otherwiseapproved by the Engineer.5.2 Cut off or build up the test pile as necessary

32、 to permitconstruction of the load-application apparatus, placement ofthe necessary testing and instrumentation equipment, andobservation of the instrumentation. Remove any damaged orunsound material from the pile top and prepare the surface sothat it is perpendicular to the pile axis with minimal i

33、rregularityto provide a good bearing surface for a test plate.5.3 For tests of single piles, install a solid steel test plate atleast 25 mm (1 in) thick perpendicular to the long axis of thetest pile that covers the complete pile top area. The test plateshall span across and between any unbraced fla

34、nges on the testpile.5.4 For tests on pile groups, cap the pile group withsteel-reinforced concrete or a steel load frame designed for theanticipated loads. Provide a clear space beneath the pile cap asspecified by the Engineer to eliminate any bearing on theunderlying ground surface. For each loadi

35、ng point on the pilecap, provide a solid steel test plate oriented perpendicular tothe axis of the pile group with a minimum thickness of 25 mm(1 in), as needed to safely apply load to the pile cap. Center asingle bearing plate on the centroid of the pile group. Locatemultiple bearing plates symmetr

36、ically about the centroid of thepile group. Boxes and beams may bear directly on the pile capwhen designed to bear uniformly along their contact surfacewith the cap.5.5 To minimize stress concentrations due to minor irregu-larities of the pile top surface, set test plates bearing on the topof precas

37、t or cast-in-place concrete piles in a thin layer ofquick-setting, non-shrink grout, less than 6 m (0.25 in) thickand having a compressive strength greater than the test pile atthe time of the test. Set test plates, boxes, and beams designed3Available from American Society of Mechanical Engineers (A

38、SME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.D 1143/D 1143M 072to bear on a concrete pile cap in a thin layer of quick-setting,non-shrink grout, less than 6 mm (0.25 in) thick and having acompressive strength greater than the pile cap at the time

39、 of thetest. For tests on steel piles, or a steel load frame, weld the testplate to the pile or load frame. For tests on individual timberpiles, set the test plate directly on the cleanly cut top of the pile,or in grout as described for concrete piles.NOTE 2Deep foundations sometimes include hidden

40、defects that maygo unnoticed prior to the static testing. Low strain integrity tests asdescribed in D 5882 and ultrasonic crosshole integrity tests as described inD 6760 may provide a useful pre-test evaluation of the test foundation.6. Apparatus for Applying and Measuring Loads6.1 General:6.1.1 The

41、 apparatus for applying compressive loads to a testpile or pile group shall conform to one of the methodsdescribed in 6.36.6 Unless otherwise specified by the Engi-neer, the apparatus for applying and measuring loads describedin this section shall be capable of safely applying at least120 % of the m

42、aximum anticipated test load. Use the methoddescribed in 6.3 to apply axial loads to either vertical orinclined piles or pile groups. Use the methods described in6.4-6.6 to apply only vertical loads.6.1.2 Align the test load apparatus with the longitudinal axisof the pile or pile group to minimize e

43、ccentric loading. Whennecessary to prevent lateral deflection and buckling along theunsupported pile length, provide lateral braces that do notinfluence the axial movement of the pile, or pile cap.6.1.3 Each jack shall include a hemispherical bearing orsimilar device to minimize lateral loading of t

44、he pile or group.The hemispherical bearing should include a locking mecha-nism for safe handling and setup. Center bearing plates,hydraulic jack(s), load cell(s), and hemispherical bearings onthe test beam(s), test pile, or test pile cap.6.1.4 Provide bearing stiffeners as needed between theflanges

45、of test and reaction beams. Provide steel bearing platesas needed to spread the load from the outer perimeter of thejack(s), or the bearing surface of beams or boxes, to bear on thesurface of the test pile or pile cap. Also provide steel bearingplates to spread the load between the jack(s), load cel

46、ls, andhemispherical bearings, and to spread the load to the testbeam(s), test pile, or pile cap. Bearing plates shall extend thefull flange width of steel beams and the complete top area ofpiles, or as specified by the Engineer, so as to provide fullbearing and distribution of the load.6.1.5 Unless

47、 otherwise specified, provide steel bearingplates that have a total thickness adequate to spread the bearingload between the outer perimeters of loaded surfaces at amaximum angle of 45 to the loaded axis. For center holejacks and center hole load cells, also provide steel platesadequate to spread th

48、e load from their inner diameter to thetheir central axis at a maximum angle of 45 , or permanufacturer recommendations. Bearing plates shall extendthe full width of the test beam(s) or any steel reaction membersso as to provide full bearing and distribution of the load.6.1.6 A qualified engineer sh

49、all design and approve allloading apparatus, loaded members, support frames, and load-ing procedures. The test beam(s), load platforms, and supportstructures shall have sufficient size, strength, and stiffness toprevent excessive deflection and instability up to the maximumanticipated test load.NOTE 3Rotations and lateral displacements of the test pile or pile capmay occur during loading, especially for piles extending above the soilsurface or through weak soils. Design and construct the support reactionsto resist any undesirable rotations or lateral displacements6.2