1、Designation: D7299 06 D7299 12Standard Practice forVerifying Performance of a Vertical Inclinometer Probe1This standard is issued under the fixed designation D7299; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This practice describes three function tests that together can be used to verify that a vertical inclinometer probe i
3、s workingproperly.1.2 This practice does not address calibration routines, electronic diagnostics, or repair of the probe, nor does it addressinspection of the probes mechanical parts.1.3 This practice is not intended to replace manufacturers recommendations for servicing and calibration of inclinom
4、eterequipment, nor is it intended to replace maintenance and calibration schedules established by users as part of their qualityprograms.1.4 UnitsThe values stated in SI units are to be regarded as standard. No other units of measurement are included in thisstandard.1.5 This practice offers a set of
5、 instructions for performing one or more specific operations. This document cannot replaceeducation or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may beapplicable in all circumstances. This ASTM standard is not intended to represent or r
6、eplace the standard of care by which theadequacy of a given professional service must be judged, nor should this document be applied without consideration of a projectsmany unique aspects. The word “standard” in the title of this document means only that the document has been approved throughthe AST
7、M consensus process.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to u
8、se.2. Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil, Rock, and Contained FluidsD3740 Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used inEngineering Design and Construction3. Terminology3.1 For definitions of term
9、s used in this practice, refer to Terminology D653.3.2 Definitions:Definitions of Terms Specific to This Standard:3.1.1 Terms not defined below may appear in Terminology D653.3.2.1 inclinometer casing, nA special-purpose pipe, typically installed in boreholes, with internal guide grooves that contro
10、lthe orientation of the inclinometer probe and that provide a flat surface for repeatable tilt measurements.3.2.2 survey, nA set of readings obtained with the inclinometer probe and readout.3.2.3 vertical inclinometer probe, nA wheeled device used to measure the tilt of inclinometer casing that is i
11、nstalled in avertical borehole. The wheels of the device track the grooves of the inclinometer casing and also keep the body of the probecentralized within the casing. Typically there are two sensors inside the device, each capable of reporting positive and negative1 This practice is under the juris
12、diction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.23 on Field Instrumentation.Current edition approved Nov. 1, 2006July 1, 2012. Published December 2006September 2012. Originally approved in 2006. Last previous edition approved in 2006 asD729906. DOI
13、: 10.1520/D7299-06.10.1520/D7299-12.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an
14、 ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. I
15、n all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1values
16、. One sensor measures tilt in the plane of the wheels and is commonly known as the A-axis sensor. The other sensor measurestilt in the plane normal to the wheels and is commonly known as the B-axis sensor.3.2.4 zero offset, nNon-zero values reported by the A-axis and B-axis sensors when the probe is
17、 held precisely vertical.4. Significance and Use4.1 Inclinometer monitoring programs often run several years or more. During this time, hundreds of surveys can be collected.Each new survey is processed by comparing it to a baseline survey.4.2 Over a period of years, normal wear and tear can graduall
18、y degrade the probes ability to produce new surveys that aredirectly comparable to the baseline survey. This may go unnoticed for some time, because the quality of readings may degrade invery small increments.4.3 When function tests are incorporated into an inclinometer monitoring program, the degra
19、dation of reading quality can beavoided. Probes that pass the tests can be used with confidence. Probes that fail the tests should be returned to the probemanufacturer for servicing. It should be noted that manufacturers calibrate inclinometer probes using high-precision,electronically-controlled eq
20、uipment in temperature-controlled environments. Ordinary users do not have access to such equipment,so the pass/fail criteria suggested for these tests accommodate typical results produced by less precise equipment in a lesscontrolled environment.4.4 The quality of the result produced by this standa
21、rd is dependent on the competence of the personnel performing it and thesuitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capableof competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned
22、 that compliance with PracticeD3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means ofevaluating some of those factors.NOTE 1The quality of the result produced by this standard is dependent on the competence of the personnel perfor
23、ming it and the suitability of theequipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objectivetesting/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself a
24、ssure reliable results. Reliableresults depend on many factors; Practice D3740 provides a means of evaluating some of those factors.5. Apparatus5.1 Two pieces of equipment are suggested: a rotary table test stand and a test casing. All the tests could be performed usingonly the rotary table test sta
25、nd, but operation of the rotary table requires a trained operator working slowly and deliberately. Thetest casing, on the other hand, provides a simple test that can be used frequently by any inclinometer user after a few minutes oftraining.5.2 Rotary Table Test Stand5.2.1 The rotary table test stan
26、d (Fig. 1) consists of a rotary table mounted on a pedestal. The rotary table is a device that iscommonly used in precision machining operations. In machine shops, rotary tables are usually mounted horizontally. In this case,the table is mounted vertically, so that it can move the probe through its
27、specified tilt range. A suitable rotary table will offer aFIG. 1 Rotary Table Test StandD7299 122placement accuracy of 30 seconds of arc or better throughout its range. It should provide an adjustable dial on the hand wheel thatreads directly to each minute of arc, and a vernier plate that permits d
28、irect reading to within 5 s. The vernier scale is used to makethe various test measurements.5.2.2 Make the pedestal from a steel I-beam or a 6-inch (150 mm) diameter steel pipe steel pipe approximately 150 mm diameterand cut to a convenient height. Steel is a commonly available material but other me
29、tals may be also be suitable. Make plates forthe top and bottom of the pedestal using 0.5-in. (12.5 mm) thick steel. Mill the top plate flat for proper mounting of the rotary table.Drill bolt holes in the base plate, as shown in Fig. 1. Weld the steel plates to the two ends of the beam or pipe. Choo
30、se a locationfor the stand and set bolts into stable flooring, such as a concrete floor slab. Ideally, the location will be free from vibration. Placethe test stand onto the bolts. Place steel shims under the bottom plate so that the top plate is completely horizontal, as indicatedby a machinists bu
31、bble level. Tighten nuts on the floor bolts.5.2.3 Mount the rotary table to the top plate as shown in Fig. 1Figure 1. . Place steel shims as necessary to make the plane ofthe table vertical. Make a probe holder from 2-in. (50 mm) square-section 6061 T6 aluminum tubing. aluminum tubingapproximately 5
32、0 mm square-section. The square section tubing holds the wheels tightly, in a fixed, repeatable position.Inclinometer casing is not a suitable substitute for the tubing, since casing grooves are purposely made wider to facilitate passageof the probe through deformed casing. Mount the probe holder to
33、 the rotary table using two V-blocks, fitting the holder so that itprovides two possible positions for the probe, one parallel to the rotary table, and the other perpendicular to the table.5.2.4 Devise a means of applying a constant torque to the table to compensate for backlash in the gears and imp
34、rove theprecision with which the table can be rotated. Fig. 1 shows a weight suspended from a wire rope that is attached to the table. Wrapthe wire rope over the top of the table so that the weight assists rotation toward positive angles (typically clockwise) as read fromthe scales on the rotary tab
35、le.5.3 Test Casing5.3.1 The test casing (Fig. 2) consists of a short length of inclinometer casing, a steel pipe of sufficient diameter to holdinclinometer casing, and a square steel base plate that can be secured to bolts set into a concrete floor slab.5.3.2 Drill bolt holes in the base plate. Weld
36、 the steel pipe to the base plate. Attach a bottom cap to the inclinometer casingand seal it so that grout will not enter. Place inclinometer casing inside the steel pipe. Align the casing so that its four guide groovespoint to the four sides of the base. Use cement grout to fix the casing within th
37、e pipe.5.3.3 Place the completed test casing onto the floor bolts, but do not tighten the nuts yet.5.3.4 Choose one of the four grooves in the casing to be the A+ groove. Mark it as the A+ groove. The B+ groove is located90 clockwise. Mark it as the B+ groove.5.3.5 Connect the probe to the readout,
38、and turn on the power. Orient the probe so that the upper wheels of both wheel sets arealigned with the A+ groove, and insert the probe into the casing. Allow the probe 10 minfor warm up.5.3.6 Calculate what value on the display is the equivalent of 1. Use the manufacturers instrument constant to co
39、nvert fromdisplay units to degrees. Tilt the test casing until the display shows the equivalent of 1 tilt in both the A+ and B+ directions. Placesteel shims under the base plate to maintain this tilt and then tighten the bolts. Installing the test casing with this small tilt ensuresthat test reading
40、s will maintain their expected signs regardless of any zero offset in the sensors.FIG. 2 Test CasingD7299 1236. Test of Repeatability6.1 This test verifies that the probe can provide repeatable readings at a selected test angle after it has been moved through itsentire tilt range, which is nominally
41、 630 for most probes.6.2 The test employs the rotary table test stand and requires an understanding of the rotary table and how its scales are read.To make positioning of the table as precise as possible, always approach the test angle from the direction opposite that of theapplied torque of the sus
42、pended weight. In other words, if the applied torque acts clockwise, approach the test angles via acounter-clockwise rotation. If a clockwise rotation is required to reach the test angle, then the table should be rotated through thetest angle, passing it by about 20 arc-min, and then returned to the
43、 test angle by a counter-clockwise rotation.6.3 Connect control cable to the probe and to the readout. Switch on the readout to provide power to the probe. Wait 10 min,with the probe powered, before continuing the procedure.6.4 Begin the A-axis test. Hold the probe so that its wheels are parallel wi
44、th the rotary table and the upper wheel of each wheelset is pointed toward the direction of positive angles. Insert the probe into the probe holder.6.5 Rotate the table to a starting point of -90. Now rotate the table through the zero to about +1 20. Then slowly return thetable to exactly +1. Do not
45、 overshoot the +1 mark. If this happens, start again from the -90 position.6.6 With the table at exactly +1, record the reading. This will be the target reading for the subsequent steps.6.7 Rotate the table to a new starting point of +90. Then rotate the table back toward +1. Watch the display and s
46、low therotation speed as the target reading is approached. Continue until the target reading is displayed. If the target reading is missed,start again from +90.6.8 With the target reading displayed, check the vernier scale. It should show no more than 6 30 arc-seconds away from +1.Repeat steps 3 thr
47、ough 5 to obtain a second set of readings. Again, the repeatability should be within 6 30 arc-seconds from +1on the vernier scale.6.9 Begin the B-axis test. Withdraw the probe from the holder, rotate it 90 counter clockwise, and reinsert it. Rotate the tableto the negative side of zero. The B-axis r
48、eading should a negative number. If it is not, withdraw the probe from its holder, rotateit 180 and reinsert.6.10 Repeat steps 3 through 6 for the B axis. Use the same pass/fail criterion of +/- 30 arc-seconds away from +1on the vernierscale.7. Test of Conformity7.1 This test verifies that the outpu
49、t of the probe at a given tilt is within acceptable tolerances.7.2 The rotary table test stand is used for this procedure. Good control of the rotary table is required. Readings are taken at sixtest angles: +30, + 20, +10, -10 -20 -30.7.3 Connect control cable to the probe and to the readout. Switch on the readout to provide power to the probe. Wait 10 min,with the probe powered, before continuing the procedure.7.4 Begin the A-axis test. Orient the probe so that its wheels are parallel with the rotary table and slide it into the probe holder.