1、Designation: D1195/D1195M 09Standard Test Method forRepetitive 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 D1195/D1195M; the number immediately following the des
2、ignation 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 a pro
3、cedure for making repeti-tive static plate load tests on subgrade soils and compactedpavement components, in either the compact condition or thenatural state, and provides data for use in the evaluation anddesign of rigid and flexible-type airport and highway pave-ments.1.2 The values stated in eith
4、er 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.1.3 This standar
5、d 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 practices and determine the applica-bility of regulatory limitations prior to use.2. Terminology2.1 Definitions:2
6、.1.1 deflection, nthe amount of downward verticalmovement of a surface due to the application of a load to thesurface.2.1.2 rebound deflection, nthe amount of vertical reboundof a surface that occurs when a load is removed from thesurface.2.1.3 residual deflection, nthe difference between originalan
7、d final 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 repetitive static plate load tests are usedfor the evaluation and design of pavement structures. Repeti-tive static plate load tests are p
8、erformed on soils and unboundbase and subbase materials to determine a measure of the shearstrength of pavement components.4. Apparatus4.1 Loading DeviceA truck or trailer or a combination ofboth a tractor-trailer, an anchored frame, or other structureloaded with sufficient weight to produce the des
9、ired 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, capable of applying and releasi
10、ng the load inincrements. The jack shall have sufficient capacity for applyingthe maximum load required, and shall be equipped with anaccurately calibrated gauge that will indicate the magnitude ofthe applied load.4.3 Bearing PlatesA set of circular steel bearing platesnot less than 25.4 mm 1 in. in
11、 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 different plate sizes is reco
12、mmended 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 tire pressure. For the purposeo
13、f 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 Gauges, two or more, graduated in units of 0.03mm 0.001 in. and capable of recording a maximum deflection
14、of 25 mm 1 in. or other equivalent deflection-measuringdevices.4.5 Deflection BeamA beam upon which the dial gaugesshall be mounted. The beam shall be a 64-mm 212-in.standard black pipe or a 76 by 76 by 6-mm 3 by 3 by14-in.steel angle or equivalent. It shall be at least 5.5 m 18 ft longand shall res
15、t on supports located at least 2.4 m 8 ft from the1This test method is under the jurisdiction of ASTM Committee E17 on Vehicle- Pavement Systems and is the direct responsibility of Subcommittee E17.41 onPavement Management and Data Needs.Current edition approved Nov. 1, 2009. Published December 2009
16、. Originallyapproved in 1952. Last previous edition approved in 2004 as D1195 93 (2004).DOI: 10.1520/D1195_D1195M-09.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.circumference of the bearing plate or nearest wheel or support-ing l
17、eg. The entire deflection measuring system shall beadequately shaded from direct rays of the sun.4.6 Miscellaneous Tools, including a spirit level, for prepa-ration of the surface to be tested and for operation of theequipment.5. Procedure5.1 Carefully center a bearing plate, of the selected diam-et
18、er, under the jack assembly. Set the remaining plates ofsmaller diameter concentric with, and on top of, the bearingplate. Set the bearing plate level in a thin bed of a mixture ofsand and plaster of Paris, of plaster of Paris alone, or of finesand, using the least quantity of materials required for
19、 uniformbearing. To prevent loss of moisture from the subgrade duringthe load test, cover the exposed subgrade to a distance of 1.8 m6 ft from the circumference of the bearing plate with atarpaulin or waterproof paper.5.2 Where unconfined load tests are to be made at a depthbelow the surface, remove
20、 the surrounding material to providea clearance equal to one-and-one-half plate diameters from theedge of the bearing plate. For confined tests, the diameter of theexcavated circular area shall be just sufficient to accommodatethe selected bearing plate.5.3 Use a sufficient number of dial gauges, so
21、 located andfixed in position as to indicate the average vertical movementof the bearing plate. When using two dial gauges, they shall beset near each extremity of a diameter of the bearing plate, 25.4mm 1 in. from the circumference. When three gauges areused, they shall be set at an angle of 120 fr
22、om each other, andequidistant from the circumference of the bearing plate. Eachindividual set of readings shall be averaged, and this value isrecorded as the average settlement reading.5.4 After the equipment has been properly arranged, andwith all of the dead load (jack, plates, and so forth) actin
23、g, seatand bearing plate and assembly by the quick application andrelease of a load sufficient to produce a deflection of not lessthan 0.25 mm 0.01 in. nor more than 0.51 mm 0.02 in. asindicated by the dial gauges. When the dial needles come torest following the release of this load, reseat the plat
24、e byapplying one half of the recorded load producing the 0.25- to0.51-mm 0.01 to 0.02-in. deflection. When the dial needleshave again come to rest, set each dial accurately at its zeromark.NOTE 2The use of additional dial gauges, placed on the surface of thematerial being tested at one half, one, an
25、d one and one-half, and so forth,bearing-plate diameters from the edge of the bearing plate, is optional.5.5 Apply a load giving a deflection of about 1.0 mm 0.04in., start a stop watch, and maintain the same load constantlyuntil the rate of deflection is 0.03 mm 0.001 in. per min orless for 3 min s
26、uccessively. Then completely release the load,and observe the rebound until the rate of recovery is 0.03 mm0.001 in. per min or less, for three successive minutes. Applyand release the same load in this manner six times. Record thereadings of the dial gauges resting on the bearing plate at theend of
27、 each minute; record the readings of the dial gauges setbeyond the perimeter of the bearing plate just before theapplication, and just before the release of load, for eachrepetition. To ensure good contact between the gauges and thebearing plate or other surface on which they are resting, brieflybuz
28、z an electric bell attached to the deflection beam, 10 sbefore the dial gauges are to be read.5.6 Increase the load to give a deflection of about 5.1 mm0.2 in., and proceed as directed in 5.5.5.7 Increase the load to give a deflection of about 10.2 mm0.4 in., and proceed as directed in 5.5.5.8 In al
29、l cases the standard end point shall be a rate of 0.03mm 0.001 in./min or less for 3 min successively.5.9 From a thermometer suspended near the bearing plate,read and record the air temperature at -h intervals.6. Record of Tests6.1 In addition to the continuous listing of all load, deflec-tion, and
30、temperature data, as prescribed in Section 5, a recordshall 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 r
31、outine procedure,6.1.6 Any unusual conditions observed at the test site, and6.1.7 Any unusual observations made during the test.7. Calculation and Plotting of Load-DeflectionRelationships7.1 For each repetition of each load, determine the deflec-tion at which the rate of deflection is exactly 0.03 m
32、m 0.001in./min. This is termed end point deflection and can bedetermined with sufficient accuracy from visual inspection ofthe deflection data for each repetition of load recorded.7.2 Correct the recorded loads, as read from the pressuregauge of each hydraulic jack used, by means of the calibrationc
33、urve for each jack and pressure gauge used.7.3 Determine graphically the zero point corrections forboth applied load and deflection. This requires taking intoaccount the weight of the hydraulic jack, that of the pyramid ofbearing plates, and so forth, and that of the corrected jack loadsat which the
34、 dial gauges were set to zero at the beginning of thetest.7.4 Plot the corrected deflection at which the rate ofdeflection is exactly 0.03 mm 0.001 in./min versus thenumber of repetitions of each corrected load. Similar graphsmay be prepared in which corrected residual deflection andrebound deflecti
35、on are plotted versus the number of repetitionsof each corrected load.8. Precision and Bias8.1 The precision and bias of this test method for makingrepetitive static plate load tests on subgrade soils and flexiblepavement components has not been determined. Soils andflexible pavement components at t
36、he same location may exhibitsignificantly different load-deflection relationships. No methodpresently exists to evaluate the precision of a group ofrepetitive plate load tests on soils and flexible pavementcomponents because of the variability of these materials. TheD1195/D1195M 092subcommittee is s
37、eeking pertinent data from users of thismethod that may be used to develop meaningful statements ofprecision and bias.9. Keywords9.1 bearing plate; deflection; pavementsASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin
38、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 committee and must
39、 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 a meeting of ther
40、esponsible 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 Drive, PO Box C700,
41、 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/).D1195/D1195M 093
