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Designation D 11 94 – 94 Standard Test Method for Bearing Capacity of Soil for Static Load and Spread Footings1 This standard is issued under the fixed designation D 1194; the number immediately follo[.]

NOTICE: This standard has either been superceded and replaced by a new version or discontinued Contact ASTM International (www.astm.org) for the latest information Designation: D 1 94 – 94 Standard Test Method for Bearing Capacity of Soil for Static Load and Spread Footings This standard is issued under the fixed designation D 1194; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision A number in parentheses indicates the year of last reapproval A superscript epsilon (e) indicates an editorial change since the last revision or reapproval Th is s ta n da rd has been a p p ro ve d f or use by a g e n cie s o f th e D e p a rtm e n t suring the force exerted by the jack The force-measuring devices should be capable of recording the load with an error not exceeding % of the load increment used 3.3 —Three circular steel bearing plates, not less than in (25 mm) in thickness and varying in diameter from 12 to 30 in (305 to 762 mm), including the minimum and maximum diameter specified or square steel bearing plates of equivalent area As an alternative, three small concrete footings of the size mentioned or larger can be cast Such footings must have a depth of not less than two thirds of their width 3.4 , such as dial gages, capable of measuring settlement of the test plates to an accuracy of at least 0.01 in (0.25 mm) 3.5 , including loading columns, steel shims, and other construction tools and equipment required for preparation of the test pits and loading apparatus Scope 1.1 This test method covers estimation of the bearing capacity of soil in place by means of field loading tests This test method can be used as part of a procedure for soil investigation for foundation design It gives information on the soil only to a depth equal to about two diameters of the bearing plate, and takes into account only part of the effect of time 1.2 The values stated in inch-pound units are to be regarded as the standard The SI units given in parentheses are for information only 1.3 Th is saf e ty s ta n da rd c o n c e rn s , re s p o n s ib ility p ria te b ility saf e ty if o f th e and e s a n y, use r h e a lth o f re g u la to ry not p u rp o rt a s s o c ia te d o f th is s ta n da rd p c tic e s lim ita tio n s to and p rio r a ddre s s w ith its to It e s ta b lis h de te rm in e to a ll use th e of th e is th e B e a rin g Se ttle m e n t- R e co rdin g a p p ro - a p p lic a - Mis c e lla n e o u s use 2.1 This test method is used to estimate the bearing capacity of a soil under field loading conditions for a specific loading plate and depth of embedment The bearing capacity of a soil is not simply a soil strength parameter, but it also depends on the magnitude and distribution of the load, dimension, and geometry of the loading plate and depth of embedment (or elevation of testing) This bearing capacity can be used in soil investigations and for the design of foundations 4.1 —Base the selection of representative test areas for bearing tests on the results of exploratory borings and on the design requirements of the structure Unless otherwise specified, make the load test at the elevation of the proposed footings and under the same conditions to which the proposed footings will be subjected At the selected elevation place the bearing plates at the same relative depths (depths expressed in plate diameters) as the actual footing 3.1 of sufficient size and strength to supply the estimated total load required or equivalent means of supplying the total load reaction anticipated 3.2 of sufficient capacity to provide and maintain the maximum estimated load for the specific soil conditions involved, but not less than 50 tons (440 kN) in any case, and at least one device, such as a pressure gage, electronic load cell, or proving ring, for meaP la tfo rm s Hy dra u lic or or B in s Me c h a n ic a l Ja c k A s s e m b ly AS TM Int' l 0 B arr H arbo r D ri ve, ( all rig hts res erved) ; PO Box C700 , Wed Jul 15 Wes t C o n s h o h o cke n , 23 : : ED T 201 PA 42 8- 59 , U n i te d S tate s D o w nlo aded/p rinted b y Alderman Lib rary ( Alderman Lib rary) p urs uant to Lic ens e Ag reement No of T e s t A re a s NOTE 2—For footings placed under permanently excavated basements the depth of the actual footing is construed as the depth from the basement level or depth over which the surcharge is permanently acting, rather than the depth from the ground surface NOTE 3—If the mentioned condition of equal relative depth cannot be met for practical reasons, the test results must be interpreted by using an This test method is under the jurisdiction ofASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.08 on Special and Construction Control Tests Current edition approved March 15, 1994 Published May 1994 Originally published as D 1194 – 52 T Last previous edition D 1194 – 72 (1987) e1 I n tern ati o n al , A p p a tu s Procedure Se le c tio n Lo a di n g D e v ic e s NOTE 1—Testing assemblies may vary widely, depending on job conditions, testing requirements, and equipment available The testing assembly and program should be planned in advance and approved by the supervising engineer, and in general can permit considerable latitude in details within the specific requirements noted above and outlined in the following test procedure A typical assembly for conducting load tests is illustrated in Fig Apparatus C o p yrig ht b y Pla te s in - s itu Significance and Use C o pyri g h t © AS TM of De f e n se further rep ro duc tio ns autho riz ed NOTICE: This standard has either been superceded and replaced by a new version or discontinued Contact ASTM International (www.astm.org) for the latest information D 1 94 – FI G Typi cal Setu p fo r Con d u cti n g Stati c Lo ad Tests appropriate theory of bearing capacity Also make corrections for the effects of the shape and size of the footing and the effects of the water table as appropriate load until the settlement has ceased or the rate of settlement becomes uniform However, maintain any type of time interval so selected for each load increment in all tests of any series 4.2 Test Pits—At least three test locations are required, and the distance between test locations shall not be less than five times the diameter of the largest plate used in the tests Carefully level and clean the areas to be loaded by the test plates or footings so that the loads are transmitted over the entire contact areas on undisturbed soil Prior to loading, protect test pits and areas against moisture changes in the soil unless it is expected that wetting of the soil will occur at some future time, as in the case of hydraulic structures In this case, prewet the soil in the area to the desired extent to a depth not less than twice the diameter of the largest bearing plate 4.3 Loading Platforms—Support the loading platforms or bins by cribbing or other suitable means, at points as far removed from the test area as practicable, and preferably not less than ft (2.4 m) The total load required for the test shall be available at the site before the test is started 4.4 Dead Load—Weigh and record as dead weight all equipment used, such as steel plates, loading column and jack, etc., that are to be placed on the test area prior to the application of the load increments 4.5 Reference Beam—Independently support the beam supporting dial gages or other settlement-recording devices as far as practicable, but not less than ft (2.4 m) from the center of the loaded area 4.6 Load Increments—Apply the load to the soil in cumulative equal increments of not more than 1.0 ton/ft2 (95 kPa), or of not more than one tenth of the estimated bearing capacity of the area being tested Accurately measure each load, and apply it in such a manner that all of the load reaches the soil as a static load, without impact, fluctuation, or eccentricity 4.7 Time Interval of Loading—After the application of each load increment, maintain the cumulative load for a selected time interval of not less than 15 4.8 Measurement of Settlement—Keep a continuous record of all settlements Make settlement measurements as soon as possible before and after the application of each load increment, and at such equal time intervals, while the load is being held constant, as will provide not less than six settlement measurements between load applications 4.9 Termination of Tests—Continue each test until a peak load is reached or until the ratio of load increment to settlement increment reaches a minimum, steady magnitude If sufficient load is available, continue the test until the total settlement reaches at least 10 % of the plate diameter, unless a welldefined failure load is observed After completion of observations for the last load increment, release this applied load in three approximately equal decrements Continue recording rebound deflections until the deformation ceases or for a period not smaller than the time interval of loading NOTE 5—The following alternative loading procedure is also permissible: Apply the load to the soil in increments corresponding to settlement increments of approximately 0.5 % of the plate diameter After the application of each settlement increment, measure the load at some fixed time intervals, for example, 30 s, min, min, min, min, and 15 min, after load application, until the variation of the load ceases or until the rate of variation of the load, on a load versus logarithm-of-time scale becomes linear Continue loading in selected settlement increments Termination of tests and unloading are made in the same manner as in 4.9 Report 5.1 In addition to the continuous listing of all time, load, and settlement data for each test, as prescribed in Section 3, report all associated conditions and observations pertaining to the test, including the following: 5.1.1 Date, 5.1.2 List of personnel, 5.1.3 Weather conditions, 5.1.4 Air temperature at time of load increments, and NOTE 4—Longer time intervals may be determined by maintaining the C o p yrig ht b y AS TM Int' l ( all rig hts res erved) ; Wed Jul 15 23 : : ED T 201 D o w nlo aded/p rinted b y Alderman Lib rary ( Alderman Lib rary) p urs uant to Lic ens e Ag reement No further rep ro duc tio ns autho riz ed NOTICE: This standard has either been superceded and replaced by a new version or discontinued Contact ASTM International (www.astm.org) for the latest information D 1 94 – 94 Irregularity in routine procedure loading plate not allow for the repetitive duplication of test results required to obtain a meaningful statistical evaluation Precision and B ias The subcommittee is seeking pertinent data from users of this The precision and bias of this test method for determin- method which may be used to develop meaningful statements ing the bearing capacity of soil in place by means of a field of precision and bias loading test has not been determined No available methods provide absolute values for the bearing capacity of soil in place Keywords against which this method can be compared The variability of the soil and the resulting disturbance of the soil under the bearing capacity; bearing plate; deflection; settlement ASTM I n tern ati on al takes n o posi ti on respecti n g th e val i d i ty of an y paten t ri g h ts asserted i n n ecti on wi th an y i tem m en ti on ed i n th i s stan d ard U sers of th i s stan d ard are expressl y ad vi sed th at d eterm i n ati on of th e val i d i ty of an y su ch paten t ri g h ts, an d th e ri sk of i n fri n g em en t of su ch ri g h ts, are en ti rel y th ei r own respon si bi l i ty Th i s stan dard i s su bj ect to revi si on at an y ti m e by th e respon si bl e tech n i cal com m i ttee an d m u st be revi ewed every fi ve years an d i f n ot revi sed , ei th er reapproved or wi th d rawn You r com m en ts are i n vi ted ei th er for revi si on of th i s stan d ard or for 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