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D 33.85
<br /> Mariotte tubes. As soon as the fluid level becomes basically 9.1.2 For the annular space between rings calculate as
<br /> constant, determine the fluid depth in the inner ring and in the follows:
<br /> annular space to the nearest 2 mm(IA6 in.)using a ruler or tape VA=Av„I(Ap Ar) (2)
<br /> Ik measure. Record!these depths. If the depths between the inner
<br /> ring and annular space varies more than 5 mm(1/4in.),raise the where:
<br /> depth gage, constant-level float valve, or Mariotte tube having VA = annular space incremental infiltration velocity,
<br /> the shallowest depth. cm/h,
<br /> r' 8.6.7 Maintain the liquid level at the selected head in both AV, = volume of liquid used during time interval to
<br /> the inner ring and annular space between rings as near as maintain constant head in the annular space be-
<br /> possible throughout the test, to prevent flow of fluid from one tween the rings, cm , and
<br /> ring to the other.' AA = area of annular space between the rings, cm2.
<br /> Non 6---'Ibis most likely will require either a continuing adjustment of 10, Report
<br /> the flow control valve on the graduated cylinder, or the use of constant-
<br /> 4t•
<br /> level float valves.A;rapid change in temperature may eliminate use of the 10.1 Report the following information in the report or field
<br /> Mariotte tube. If records, or both:
<br /> 8.7 Measurements: 10.1.1 location of test site.
<br /> }: 10.1.2 Dates of test, start and.finish.
<br /> 8.7.1 Record the ground temperature at a depth of about 300
<br /> 10.1.3 Weather conditions, start to finish.
<br /> mm(12 in.), or at the mid-depth of the test zone.
<br /> 8.7.2 Determine and record the volume of liquid that is 10.1.4 Name(s) of techrtician(s).
<br /> added to maintain a constant head in the inner ring and annular 10.1.5 Description of test site, including boring profile, see
<br /> space during each timing interval by measuring the change in 10.1.11.
<br /> elevation of liquid level in the appropriate graduated cylinder 10.1.6 Type of liquid used in the test,along with the liquid's
<br /> or Mariotte tube, Also, record the temperature of the liquid PH. If available, a full analysis of the liquid also should be
<br /> within the inner ling. recorded.
<br /> ,f 10.1.7 Areas of rings and the annular space between rings.
<br /> 8.7.3 For average soils, record the volume of liquid used at 10.1.8 Volume constants for graduated cylinders or Mariotte
<br /> r intervals of 15 n for the first hour, 30 min for the second
<br /> hour,and 60 minmirduring the remainder of a period of at least 6 tubes.
<br /> h, or until after a relatively constant rate is obtained. 10.1.9 Depth of liquid in inner ring and annular space.
<br /> k 8.7.4 The appropriate schedule of readings may be deter- 10.1.10 Record of ground and liquid temperatures, incre-
<br /> mined only through experience. For high-permeability materi-
<br /> ir r mental volume measurements, and incremental infiltration
<br /> als,readings may,be more frequent,while for low-permeability velocities (inner ring and annular space) versus elapsed time. i
<br /> materials, the reading interval may be 24 h or more. In any The rate of the inner ring should be the value used if the rates f
<br /> event, the volurtie of liquid used in any one reading interval for inner ring and annular space differ. The difference in rates
<br /> 3 is due to divergent flow.
<br /> should not be less than approximately 25 cm .
<br /> 8.7.5 Place the driving cap or some other covering over the found between th10.1.11 If available, depth to the water table and a descrip-
<br /> tion of the soils ouneween e rings and thettable,water ae,or
<br /> rings during the intervals between liquid measurements to
<br /> minimize evaporation (see 8.2.1). to a depth of about 1 m {3 ft).
<br /> 8.7.6 Upon completion of the test, remove the rings from 10.1.12 A plot of the incremental infiltration rate versus ;
<br /> the soil,assisted by light hammering on the sides with a rubber
<br /> total elapsed time (see Fig. 4). ?
<br /> hammer. 10.2 An example field records form is given in Fig. 3.
<br /> 10.3 See Appendix X1 for information on the determination 4
<br /> 9. CalculationsL� of the moisture pattern.
<br /> 9.1 Convert the volume of liquid used during each measured
<br /> time inter-vat into an incremental infiltration velocity for both 11. Precision and Bias
<br /> the inner ting and annular space using the following equations: 11.1 No statement on precision and bias can be made due to
<br /> 9.1.1 For the,inner ring calculate as follows: the variability in soils tested and in the types of liquids that
<br /> V,R=AVfR!(AfR Ar) (l) might be used in this test method.Because of the many factors
<br /> related to the soils, as well as the liquids that may affect the
<br /> where: results,the recorded infiltration rate should be considered only
<br /> ViR = innerk ring incremental infiltration velocity, cm/h, as an index value.
<br /> AVrR = volume of liquid used during time interval to
<br /> maintain constant head in the inner ring, cm3, 12. Keywords
<br /> 1 AtR = internal area of inner Hing, cm-, and 12.1 coefficient of permeability; hydraulic conductivity;
<br /> At = time interval, h. infiltration rate; infiltrometer; in-situ testing; Mariotte tube
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