ASTM_D_1194_-_94_scan.pdf

Designation:D 1194-94AMERICAN SOCIETY FOR TESTING AND MATERIALS1916RSL PhCopyright ASTMf not listed in the current combined index,will appear in the next edition.Standard Test Method forBearing Capacity of Soil for Static Load and Spread Footings1This standard is issuod under the fixed designation D 1194;the number immediately following the designation indicates the year oforiginal adoption or.in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(indicates an editorial change since the last revision or reapproval.This standard has been approred for use by agencics of the Department of Defense.Consul the DoD Index of Specifications andStandards for the specific year of issue which has been adopted by the Depariment of Defense.1.Scopenot less than 1 in.(25 mm)in thickness and varying in1.1 This test method covers estimation of the bearingdiameter from 12 to 30 in.(305 to 762 mm),including thecapacity of soil in place by means of field loading tests.Thisminimum and maximum diameter specified or square steeltest method can be used as part of a procedure for soilbearing plates of equivalent area,As an alternative,threeinvestigation for foundation design.It gives information onsmall concrete footings of the size mentioned or larger can bethe soil only to a depth equal to about two diameters of thecast in-situ.Such footings must have a depth of not less thanbearing plate,and takes into account only part of the effecttwo thirds of their width.of time.3.4 Settlement-Recording Devices,such as dial gages,1.2 The values stated in inch-pound units are to becapable of measuring settlement of the test plates to anregarded as the standard.The SI units given in parenthesesaccuracy of at least 0.01 in.(0.25 mm).are for information only.3.5 Miscellaneous Apparatus,including loading columns,1.3 This standard does not purport to address all of thesteel shims,and other construction tools and equipmentsafety concerns,if any,associated with its use.It is therequired for preparation of the test pits and loading appa-responsibility of the user of this standard to establish appro-ratus.priate safety and health practices and determine the applica-NoTe 1-Testing assemblies may vary widely,depending on jobbility of regulatory limitations prior to use.conditions,testing requirements,and equipment available.The testingassembly and program should be planned in advance and approved by2.Significance and Usethe supervising engineer,and in general can permit considerable latitudein details within the specific requirements noted above and outlined in2.1 This test method is used to estimate the bearingthe following test procedure.A typical assembly for conducting loadcapacity of a soil under field loading conditions for a specifictests is illustrated in Fig.1.loading plate and depth of embedment.The bearing capacityof a soil is not simply a soil strength parameter,but it also4.Proceduredepends on the magnitude and distribution of the load,4.1 Selection of Test Areas-Base the selection of repre-dimension,and geometry of the loading plate and depth ofsentative test areas for bearing tests on the results ofembedment(or elevation of testing).This bearing capacityexploratory borings and on the design requirements of thecan be used in soil investigations and for the design ofstructure.Unless otherwise specified,make the load test atfoundations.the elevation of the proposed footings and under the same3.Apparatusconditions to which the proposed footings will be subjected.At the selected elevation place the bearing plates at the same3.1 Loading Platforms or Bins of sufficient size andrelative depths(depths expressed in plate diameters)as thestrength to supply the estimated total load required oractual footing.equivalent means of supplying the total load reaction antici-NorE 2-For footings placed under permanently excavated base-pated.ments the depth of the actual footing is construed as the depth from the3.2 Hydraulic or Mechanical Jack Assembly of sufficientbasement level or depth over which the surcharge is permanently acting.capacity to provide and maintain the maximum estimatedrather than the depth from the ground surface.load for the specific soil conditions involved,but not lessNorE 3-If the mentioned condition of equal relative depth cannotthan 50 tons(440 kN)in any case,and at least one device,be met for practical reasons,the test results must be interpreted by usingsuch as a pressure gage,electronic load cell,or proving ring,an appropriate theory of bearing capacity.Also make corrections for thefor measuring the force exerted by the jack.The force-effects of the shape and size of the footing and the effects of the watertable as appropriate.measuring devices should be capable of recording the loadwith an error not exceeding+2%of the load increment4.2 Test Pits-At least three test locations are required,used.and the distance between test locations shall not be less than3.3 Bearing Plates-Three circular steel bearing plates,five times the diameter of the largest plate used in the tests.Carefully level and clean the areas to be loaded by the testplates or footings so that the loads are transmitted over theThis test method is under the jurisdiction of ASTM Committee D-18 on Soilentire contact areas on undisturbed soil.Prior to loading,and Rock and is the direct responsibility of Subcommittee D18.10 on BearingTests of Soils in Place.protect test pits and areas against moisture changes in the soilCurrent edition approved March 15,1994.Published May 1994.Originallyunless it is expected that wetting of the soil will occur at somepublished as D 1194-52 T.Last previous edition D 1194-72(1987).future time,as in the case of hydraulic structures.In thisD1194Load P时Timbec Crobing01Anchor PilesPlc1aAnchor Rods-CompressionPostoll and Socket JoinBeordStraightedge月eferent老e0FIG.1 Typical Setup for Conducting Static Load Testscase,prewet the soil in the area to the desired extent to atude.If sufficient load is available,continue the test until thedepth not less than twice the diameter of the largest bearingtotal settlement reaches at least 10%of the plate diameter,plate.unless a well-defined failure load is observed.After comple-4.3 Loading Plalforms-Support the loading platforms ortion of observations for the last load increment,release thisbins by cribbing or other suitable means,at points as farapplied load in three approximately equal decrements.removed from the test area as practicable,and preferably notContinue recording rebound deflections until the deforma-less than 8 ft(2.4 m).The total load required for the test shalltion ceases or for a period not smaller than the time intervalbe available at the site before the test is started.of loading.4.4 Dead Load-Weigh and record as dead weight allequipment used,such as steel plates,loading column andNoTE 5-The following alternative loading procedure is also permis-sible:Apply the load to the soil in increments corresponding tojack,etc.,that are to be placed on the test area prior to thesettlement increments of approximately 0.5%of the plate diameter.application of the load increments.After the application of each settlement increment,measure the load at4.5 Reference Beam-Independently support the beamsome fixed time intervals,for example,30s,1 min,2 min,4 min,8 min,supporting dial gages or other settlement-recording devices asand 15 min,after load application,until the variation of the load ceasesfar as practicable,but not less than 8 ft(2.4 m)from theor until the rate of variation of the load,on a load versus logarithm-center of the loaded area.of-time scale becomes linear.Continue loading in selected settlementincrements.Termination of tests and unloading are made in the same4.6 Load Increments-Apply the load to the soil inmanner as in 4.9.cumulative equal increments of not more than 1.0 ton/ft2(95 kPa),or of not more than one tenth of the estimated5.Reportbearing capacity of the area being tested.Accurately measureeach load,and apply it in such a manner that all of the load5.1 In addition to the continuous listing of all time,load,reaches the soil as a static load,without impact,fluctuation,and settlement data for each test,as prescribed in Section 3.or eccentricity.report all associated conditions and observations pertaining4.7 Time Interval of Loading-After the application ofto the test,including the following:each load increment,maintain the cumulative load for a5.1.1 Date,selected time interval of not less than 15 min.5.1.2 List of personnel,5.1.3 Weather conditionsNoTE 4-Longer time intervals may be determined by maintainingthe load until the settlement has ceased or the rate of settlement becomes5.1.4 Air temperature at time of load increments,anduniform.However,maintain any type of time interval so selected for5.1.5 Irregularity in routine procedure.each load increment in all tests of any series.4.8 Measurement of Settlement-Keep a continuous6.Precision and Biasrecord of all settlements.Make settlement measurements as6.1 The precision and bias of this test method for deter-soon as possible before and after the application of each loadmining the bearing capacity of soil in place by means of aincrement,and at such equal time intervals,while the load isfield loading test has not been determined.No availablebeing held constant,as will provide not less than sixmethods provide absolute values for the bearing capacity ofsettlement measurements between load applications.soil in place against which this method can be compared.4.9 Termination of Tests-Continue each test until a peakThe variability of the soil and the resulting disturbance of theload is reached or until the ratio of load increment tosoil under the loading plate do not allow for the repetitivesettlement increment reaches a minimum,steady magni-duplication of test results required to obtain a meaningful2