1、Designation: D 5641 94 (Reapproved 2006)Standard Practice forGeomembrane Seam Evaluation by Vacuum Chamber1This standard is issued under the fixed designation D 5641; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers procedures to perform nondestruc-tive quality control testing described in Practice D 4437 andD 4545
3、 for evaluating the continuity of all types of geomem-brane seams using the bubble emission or vacuum chambermethod.1.2 The technique described in this practice is intended foruse on geomembrane seams, patches, and defects.1.3 The values stated in SI units are to be regarded as thestandard. The valu
4、es given in parentheses are for informationonly.1.4 This standard 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 reg
5、ulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 4437 Practice for Determining the Integrity of FieldSeams Used in Joining Flexible Polymeric SheetGeomembranesD 4439 Terminology for GeosyntheticsD 4545 Practice for Determining the Integrity of FactorySeams Used in Joinin
6、g Manufactured Flexible SheetGeomembranesE 515 Test Method for Leaks Using Bubble Emission Tech-niques2.2 E.P.A. Documents:EPA/530/SW-91/051 Inspection Techniques for the Fabrica-tion of Geomembrane Field Seams33. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 geomembrane, nan e
7、ssentially impermeable geo-synthetic composed of one or more synthetic sheets. (SeeTerminology D 4439).3.1.2 seam, nthe connection of two or more pieces ofmaterial by mechanical, chemical, or fusion methods to pro-vide the integrity of a single piece of the material.3.1.3 vacuum chamber, na device t
8、hat allows a vacuum tobe applied to a surface.3.1.3.1 DiscussionIn geomembranes, typical seamswould include adhesive bonded, bodied chemical fusion welds;chemical fusion welds; dielectric; dual hot wedge; fillet extru-sion; flat extrusion; hot air; single hot wedge; and ultrasonic.(See EPA/530/SW-91
9、/051.)NOTE 1For definition of other terms used in this practice, refer toTerminology D 4439.4. Summary of Practice4.1 The basic principle of this practice consists of creating apressure differential across a seam and observing for bubbles ina film of foaming solution over the low pressure side, with
10、inthe vacuum chamber. The vacuum chamber has a viewing portthat allows observation of the seam area being tested. Thefoaming solution is applied to the surface to be tested and thevacuum chamber is placed over the test area. As the chamberis held firmly in place, vacuum is applied. Air leakage throu
11、ghflaws in the test area cause bubbles in the foaming solution thatmay be observed.1This practice is under the jurisdiction of ASTM Committee D35 on Geosyn-thetics and is the direct responsibility of Subcommittee D35.10 on Geomembranes.Current edition approved June 1, 2006. Published June 2006. Orig
12、inallyapproved in 1994. Last previous edition approved in 2001 as D 5641 94 (2001)e1.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary
13、page onthe ASTM website.3Available from the Superintendent of Documents, U.S. Government PrintingOffice, Washington, DC 20402.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Significance and Use5.1 This practice is a nondestructiv
14、e evaluation intended tobe used for quality control purposes during factory or fieldseaming of geomembranes.5.2 This practice may also be used to evaluate geomem-brane panels for holes that penetrate the entire thickness ofmaterial. Limitations on the test practice are that it may not besuitable for
15、 uneven or curved surfaces, thick seams, seams incorners, and thin extensible geomembranes.6. Apparatus6.1 Vacuum PumpThe vacuum pump shall be fuel orelectric powered and capable of sustaining the requiredvacuum for the duration of the test.6.2 Vacuum GaugeThe vacuum gauge shall be capable ofregiste
16、ring, as a minimum, to 70 kPa (10 psi) in increments of5 kpa (34 psi).6.3 Calibration and AdjustmentThe calibration of thevacuum gauge shall be checked and adjusted periodically, androutinely at a minimum of once every twelve months.6.4 Foaming SolutionThe foaming solution shall be pre-mixed with wa
17、ter at a ratio conducive to the formation ofbubbles. It shall be dispensed by spray, brush, or any otherconvenient means. The foaming solution shall be compatiblewith the geomembrane.NOTE 2If the component to be tested has parts made of polyethyleneor structural plastics, the test fluid must not pro
18、mote environmental stresscracking (E.S.C.). (See Test Method E 515.)6.5 Vacuum ChamberThe vacuum chamber shall have anopen bottom and a clear viewing panel on top. It shall be anappropriate and convenient size and shape, made of rigidmaterials and equipped with a vacuum gauge, valve, and softpliable
19、 gasket around the periphery of the open bottom (seeFig. 1).NOTE 3Vacuum chamber equipment may be obtained from thesuppliers given in Footnote 5.4These suppliers are cited only forconvenience and no commercial endorsement is expressed or implied byincorporation into this practice.7. Procedure7.1 The
20、 area of the seam to be evaluated should be clean andfree of soil or foreign objects that might prohibit a good sealfrom being formed between the vacuum chamber and thegeomembrane.7.2 Energize the vacuum pump.7.3 Wet an area immediately adjacent to and including thegeomembrane seam or test area meas
21、uring approximatelytwice the width and length of the vacuum chamber with afoaming solution.7.4 Place the vacuum chamber over the wet area of thegeomembrane such that the gasket is in complete contact withthe geomembrane surface, and the test area is centered underthe viewing port.7.5 Apply a normal
22、force to the top of the vacuum chamberto effect a seal and open the vacuum valve.7.6 Ensure that a leak tight seal is created between thevacuum chamber gasket and the geomembrane material. Formost cases, a minimum vacuum of 28 to 55 kPa (4 to 8 psi) asregistered on the vacuum gauge should be appropr
23、iate.7.7 With the vacuum applied, maintain the normal force andobserve the geomembrane seam or test area through theviewing port for bubbles resulting from the flow of air throughdefects in the seam. The vacuum should be held over the testsite for a duration of not less than 10 s. If the vacuum cann
24、otbe held for the minimum 10 s, the test area shall be marked asuntested. It is essential that the viewing port remain clean at alltimes to facilitate unobstructed viewing.7.8 If bubbles appear on the geomembrane seam, turn thethree-way vacuum valve to vent the chamber and remove thevacuum chamber f
25、rom the seam. The defective area shouldthen be marked for repair.7.9 If bubbles do not appear through the geomembraneseam within the specified dwell time, turn the vacuum valve tovent the chamber and remove the chamber from the seam.7.10 Move the vacuum chamber to the adjoining portion ofthe seam or
26、 test area overlapping the previously tested area bya distance no less than 10 % of the minimum chamber lengthor at least 50 mm (2 in.), whichever is the greater and repeat theprocedure until the entire seam has been tested.8. Report8.1 Report the following information:8.1.1 Identification of the ge
27、omembrane material, includingtype of polymer, source, thickness, reinforced or nonreinforcedsheeting, seaming system used, ambient temperature, seamtested, seam width, date of seam fabrication, and date of seamevaluation, and results of seam evaluation,4Series A100 Straight Seam Tester supplied by t
28、he American Parts and ServiceCompany, 2201 West Commonwealth Avenue, P.O. Box 702, Alhambra, CA 91802.Vacuum Chamber Test System as supplied by Sinclair Equipment Company, 6686A Merchandise Way, Diamond Springs, CA 95619. Columbine International, Ltd.,5441 Merchant Circle, Placerville, CA 95667.FIG.
29、 1 Vacuum ChamberD 5641 94 (2006)2NOTE 4The intent of the form is not to imply that each VCT is to berecorded on said form.8.1.2 Documentation of the typical vacuum pressure andhold duration and latest pressure gauge calibrations,8.1.3 Identification of the location and approximate size ofall defect
30、ive areas, and8.1.4 Identification of foaming solution used for the test andif different types were used, the location of use for each type.9. Keywords9.1 bubble emission testing; geomembrane; nondestructivetesting; seam; testing; vacuum; vacuum chamberAPPENDIX(Nonmandatory Information)X1. Evaluatio
31、n FormD 5641 94 (2006)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringem
32、ent of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or
33、 for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views kn
34、own 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, 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).FIG. X1.1 Evaluation FormD 5641 94 (2006)4
