1、Designation: D1196/D1196M 12Standard Test Method forNonrepetitive Static Plate Load Tests of Soils and FlexiblePavement Components, for Use in Evaluation and Design ofAirport and Highway Pavements1This standard is issued under the fixed designation D1196/D1196M; the number immediately following the
2、designation indicates theyear of original adoption or, in the case of revision, 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.1. Scope1.1 This test method covers th
3、e making of nonrepetitivestatic plate load tests on subgrade soils and pavement compo-nents, in either the compacted condition or the natural state,and provides data for use in the evaluation and design of rigidand flexible-type airport and highway pavements.1.2 UnitsThe values stated in either SI u
4、nits or inch-pound units are to be regarded separately as standard. Thevalues stated in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the standard.1.3 This standard doe
5、s 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. Terminology2.1 Definitions:2.1.1
6、deflection, namount of downward vertical move-ment of a surface as a result of the application of a load to thesurface.2.1.2 rebound deflection, namount of vertical rebound ofa surface that occurs when a load is removed from the surface.2.1.3 residual deflection, ndifference between originaland fina
7、l elevations of a surface resulting from the applicationand removal of one or more loads to and from the surface.3. Significance and Use3.1 Field, in-place nonrepetitive static load tests are used forthe evaluation and design of pavement structures. Nonrepeti-tive static plate load tests are perform
8、ed on soils and unboundbase and subbase materials to determine the modulus ofsubgrade reaction or a measure of the shear strength ofpavement components.4. Apparatus4.1 Loading DeviceA truck or trailer or a combination ofboth a tractor-trailer, an anchored frame, or other structureloaded with suffici
9、ent weight to produce the desired reaction onthe surface under test. The supporting points (wheels in thecase of a truck or trailer) shall be at least 2.4 m 8 ft from thecircumference of the largest diameter bearing plate being used.4.2 Hydraulic Jack Assembly, with a spherical bearingattachment, ca
10、pable of applying and releasing the load inincrements. The jack shall have sufficient capacity for applyingthe maximum load required, and shall be equipped with anaccurately calibrated gage that will indicate the magnitude ofthe applied load.4.3 Bearing PlatesA set of circular steel bearing platesno
11、t less than 25.4 mm 1 in. in thickness, machined so thatthey can be arranged in pyramid fashion to ensure rigidity, andhaving diameters ranging from 152 to 762 mm 6 to 30 in.The diameters of adjacent plates in the pyramid arrangementshall not differ by more than 152 mm 6 in.NOTE 1A minimum of four d
12、ifferent plate sizes is recommended forpavement design or evaluation purposes. For evaluation purposes alone, asingle plate may be used, provided that its area is equal to the tire-contactarea corresponding to what may be considered as the most criticalcombination of conditions of wheel load and tir
13、e pressure. For the purposeof providing data indicative of bearing index (for example, the determi-nation of relative subgrade support throughout a period of a year), a singleplate of any selected size may be used.4.4 Dial Gages, two or more, graduated in units of 0.01 mmor 0.001 in. and capable of
14、recording a maximum deflectionof 25.4 mm 1 in. or other equivalent deflection-measuringdevices.4.5 Deflection Beam, upon which the dial gages shall bemounted. The beam shall be a 64 mm 212-in. standard blackpipe or a 76 by 76 by 6-mm 3 by 3 by14-in. steel angle, orequivalent. It shall be at least 5.
15、5 m 18 ft long and shall reston supports located at least 2.4 m 8 ft from the circumferenceof the bearing plate or nearest wheel or supporting leg. Theentire deflection measuring system shall be adequately shadedfrom direct rays of the sun.4.6 Miscellaneous Tools, including a spirit level, for prepa
16、-ration of the surface to be tested and for operation of theequipment.1This test method is under the jurisdiction of ASTM Committee E17 on Vehicle- Pavement Systems and is the direct responsibility of Subcommittee E17.41 onPavement Testing and Evaluation.Current edition approved Jan. 1, 2012. Publis
17、hed January 2012. Originallyapproved in 1952. Replaces D1196 57. Last previous edition approved in 2004 asD1196 93 (2004). DOI: 10.1520/D1196-12.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Procedure5.1 Carefully center a beari
18、ng plate of the selected diameterunder the jack assembly. Set the remaining plates of smallerdiameter concentric with, and on top of, the bearing plate. Setthe bearing plate level in a thin bed of a mixture of sand andplaster of paris, of plaster of paris alone, or of fine sand, usingthe least quant
19、ity of materials required for uniform bearing. Toprevent loss of moisture from the subgrade during the load test,cover the exposed subgrade to a distance of 1.8 m 6 ft fromthe circumference of the bearing plate with a tarpaulin orwaterproof paper.5.2 Where unconfined load tests are to be made at a d
20、epthbelow the surface, remove the surrounding material to providea clearance equal to one and one-half bearing plate diametersfrom the edge of the bearing plate. For confined tests thediameter of the excavated circular area shall be just sufficient toaccommodate the selected bearing plate.5.3 Use a
21、sufficient number of dial gages, so located andfixed in position as to indicate the average deflection of thebearing plate. When using two dial gages, they shall be set neareach extremity of a diameter of the bearing plate, 25.4 mm 1in. from the circumference. When three gages are used, theyshall be
22、 set at an angle of 120 from each other, and equidistantfrom the circumference of the bearing plate. Each individualset of readings shall be averaged, and this value is recorded asthe average settlement reading.5.4 After the equipment has been properly arranged, with allof the dead load (jack, plate
23、s, and so forth) acting, seat thebearing plate and assembly by the quick application and releaseof a load sufficient to produce a deflection of not less than 0.25mm 0.01 in. nor more than 0.51 mm 0.02 in., as indicatedby the dials. When the dial needles come to rest followingrelease of this load, re
24、seat the plate by applying one half of therecorded load producing the 0.25to0.51mm 0.01 to 0.02-in. deflection. When the dial needles have then again come torest, set each dial accurately at its zero mark.5.5 Apply loads at a moderately rapid rate in uniformincrements. The magnitude of each load inc
25、rement shall besmall enough to permit the recording of a sufficient number ofload-deflection points to produce an accurate load-deflectioncurve (not less than six). After each increment of load has beenapplied, maintain the load until a rate of deflection of not morethan 0.03 mm 0.001 in./min occurs
26、 for 3 min consecutively.Record load and deflection readings for each load increment.Continue this procedure until the selected total deflection hasbeen obtained, or until the load capacity of the apparatus hasbeen reached, whichever occurs first. At this point, maintainthe load until an increased d
27、eflection of not more than 0.03 mm0.001 in./min for 3 min consecutively occurs. Record thetotal deflection, after which release the load to load at whichthe dial gages were set at zero, and maintain this zero-settingload until the rate of recovery does not exceed 0.03 mm 0.001in. for 3 min consecuti
28、vely. Record the deflection at thezero-setting load.5.6 From a thermometer suspended near the bearing plate,read and record the air temperature at12 h intervals.6. Record of Tests6.1 In addition to the continuous listing of all load, deflec-tion, and temperature data, as prescribed in Section 4, a r
29、ecordshall also be made of all associated conditions and observationspertaining to the test, including the following:6.1.1 Date,6.1.2 Time of beginning and completion of test,6.1.3 List of personnel,6.1.4 Weather conditions,6.1.5 Any irregularity in routine procedure,6.1.6 Any unusual conditions obs
30、erved at the test site, and6.1.7 Any unusual observations made during the test.7. Calculation and Plotting of Load-DeflectionRelationships7.1 From the data obtained by the procedure describedunder 4.5, plot the total or unit load in Newtons pounds-forcefor each increment against the corresponding se
31、ttlement inmillimeters inches. Also plot the recovery after full release ofload. Correction should be made for the zero deflection point,taking into account the dead weight of the equipment and theseating load. From this graph, the relation of load and totaldeflection for that load, and the relation
32、 of rebound andresidual deflection for the maximum load used, may beobtained.8. Precision and Bias8.1 The precision and bias of this test method for makingnonrepetitive static plate load tests on subgrade soils andflexible pavement components has not been determined. Soilsand flexible pavement compo
33、nents at the same location mayexhibit significantly different load deflection relationships. Nomethod presently exists to evaluate the precision of a group ofnonrepetitive plate load tests on soils and flexible pavementcomponents because of the variability of these materials. Thesubcommittee is seek
34、ing pertinent data from users of this testmethod that may be used to develop meaningful statements ofprecision and bias.9. Keywords9.1 bearing plate; deflection; pavementsD1196/D1196M 122ASTM International takes no position respecting the validity of any patent rights asserted in connection with any
35、 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 responsibility.This standard is subject to revision at any time by the responsible technical
36、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 to ASTM International Headquarters. Your comments will receive careful consideration at
37、 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 address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor D
38、rive, 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), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D1196/D1196M 123
