1、Designation: D 4437 99Standard Practice forDetermining the Integrity of Field Seams Used in JoiningFlexible Polymeric Sheet Geomembranes1This standard is issued under the fixed designation D 4437; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 of revision, the year of last 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 is intended for use as a summary ofdestructive and nondestructive quality con
3、trol test methods fordetermining the integrity of field seams used in the joining offlexible sheet materials in a geotechnical application. Thispractice outlines the test procedures available for determiningthe quality of bonded seams. Any one or combination of thetest methods outlined in this pract
4、ice can be incorporated intoa project specification for quality control. These test methodsare applicable to manufactured flexible polymeric membranelinings that are scrim reinforced or nonreinforced.1.2 The types of field seams covered by this practice includethe following:1.2.1 Thermally Bonded Se
5、ams:1.2.1.1 Hot AirA seam produced by applying high-temperature air or gas between two polymeric sheet surfaces,thus melting the surfaces, at which time pressure is applied toform a homogeneous bond between the two membrane sur-faces.1.2.1.2 Hot Wedge (or Knife)A seam produced by meltingthe two inti
6、mate surfaces by running a hot metal wedgebetween the surfaces followed immediately by pressure to forma homogeneous bond.1.2.1.3 ExtrusionA bonded seam produced by extrudingmolten parent material between or at the edge of two over-lapped polymer sheet materials to effect a homogeneous meltbetween t
7、he two sheets to be joined.1.2.2 Solvent Bonded SeamsA solvent is used to softenthe surfaces to be bonded, followed by pressure to form ahomogeneous bond.1.2.3 Bodied Solvent Bonded SeamsThe parent liningpolymer material is dissolved in a solvent that is then appliedin the same manner as a straight
8、solvent, thus effecting ahomogeneous bond.1.2.4 Adhesive Bonded or Cemented Seams An adhesivesystem is used to bond two polymeric surfaces together. Thissystem forms an adhesive bond between the sheet materials.1.2.5 Taped SeamsAn adhesive-based tape is placed be-tween two polymer sheet materials fo
9、rming a surface bond.1.2.6 Waterproofed Sewn SeamsSeam fabricated by me-chanical sewing of the overlapped sheet materials and sealedwith an appropriate sealant as recommended by the sheetmanufacturer.1.3 The values stated in inch-pound units are to be regardedas the standard.1.4 This standard may in
10、volve hazardous materials, opera-tions, and equipment. This standard does not purport toaddress all of the safety concerns, if any, associated with itsuse. It is the responsibility of the user of this standard toestablish appropriate safety and health practices and deter-mine the applicability of re
11、gulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 413 Test Methods for Rubber PropertyAdhesion toFlexible Substrate2D 618 Practice for Conditioning Plastics for Testing3D 816 Methods of Testing Rubber Cements23. Significance and Use3.1 The increased use of geomembranes as
12、 barrier materialsto restrict liquid migration from one location to another in soiland rock, and the large number of seam methods and typesused in joining these geomembrane sheets, has created a needfor standard tests by which the various seams can be comparedand the quality of the seam systems can
13、be evaluated. Thispractice is intended to meet such a need.4. Materials and Manufacture4.1 The geomembrane sheet material shall be formulatedfrom the appropriate polymers and compounding ingredients toform a plastic or elastomer sheet material that meets allspecified requirements for the end use of
14、the product. The sheetmaterial (reinforced or nonreinforced) shall be capable of beingbonded to itself by one of the methods described in 1.2 inaccordance with the sheet manufacturers recommendationsand instructions.1This practice is under the jurisdiction of ASTM Committee D35 on Geosyn-thetics and
15、 is the direct responsibility of Subcommittee D35.10 on Geomembranes.Current edition approved March 10, 1999. Published March 2001. Originallypublished as D 443784. Discontinued January 1998 and reinstated as D 443799.Last previous edition D 443784 (1988).2Annual Book of ASTM Standards, Vol 09.01.3A
16、nnual Book of ASTM Standards, Vol 08.01.1Copyright ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.5. Sampling for Destructive Test Methods5.1 Field Fabricated Startup Seam The installation con-tractor shall provide a representative seam fabricated from thesame sheet mat
17、erial and using the same seaming methods asthose recommended by the geomembrane sheet manufacturer.The startup seam shall be no less than 10 ft (3 m) in length andshall be provided at the start of each days or shifts seaming.Cut random samples for shear and peel testing from the startupseam. Allow t
18、he seam to cure or age properly before testing inaccordance with manufacturers directions.5.2 Field CutoutFor a minimum of one sample perseaming crew per day, cut a 2-ft (0.61-m) long section of thefabricated seam from the installed lining. The cutout sectionshall be wide enough to accommodate peel
19、and shear testing asin 6.2 and 6.3. Cut random specimens for peel and shear testingfrom the sample. The frequency of cutouts can be determinedby the size of the geomembrane installation and may requireonly one or two cutouts. Patch the resulting hole with anoval-shaped piece of sheet material and se
20、am in accordancewith the manufacturers instructions. Before testing, allow thecutout seam to cure or age properly in accordance withmanufacturers directions.6. Destructive Test Methods6.1 These test methods are applicable only at sites whereaccess to a testing laboratory is readily available, where
21、projectscheduling will allow offsite testing, or where a portable testlaboratory is available.6.2 Peel TestingFollow Test Methods D 413, Method A,or Methods D 816, Method C, using a minimum of five l-in.(25.4-mm) wide specimens, a gage length of 1 in. (25.4 mm)(grips positioned12 in. (13.0 mm) on ei
22、ther side of the start ofseam bond), and a constant machine crosshead speed of 2in./min (51 mm/min). The seam overlap length shall be asfabricated in the field. Fully support the test specimen withinthe grips across the width of the specimen.6.3 Shear TestingFollow Methods D 816, Method B,using a mi
23、nimum of five 1-in. (25.4-mm) wide specimens forunreinforced sheet materials. For reinforced sheet materials,the following procedure shall be used: Prepare a minimum offive 2-in. (51-mm) wide specimens for reinforced sheet mate-rials with the field seam at the center of the test specimen andperpendi
24、cular to the centerline. Grip separation shall be 2 in.(51 mm) plus the width of the seam with the seam centeredbetween the grips. Crosshead speed shall be 2 in./min (51mm/min). The seam overlap shall be as fabricated in the field.Fully support the test specimen within the grips across thewidth of t
25、he specimen.7. Nondestructive Test Methods7.1 For all test methods listed below, any and all flaws inseam construction that are detected under a given test proce-dure shall be repaired. All nondestructive test methods listedare not necessarily applicable to all polymeric geomembranematerials.7.2 Air
26、 Lance TestInspect all field seams for unbondedareas using an air nozzle directed on the upper seam edge andsurface to detect loose edges, riffles indicating unbonded areaswithin the seam, or other undesirable seam conditions. Checkall bonded seams using a minimum 50 psi (345 kPa) (gage) airsupply d
27、irected through a316 in. (4.8 mm) (typical) nozzle,held not more than 2 in. (51 mm) from the seam edge anddirected at the seam edge.7.3 Vacuum Box TestingInspect all field seams for un-bonded areas by applying a vacuum to a soaped section ofseam. The vacuum shall be applied by a vacuum box equippedw
28、ith a vacuum gage, a clear glass view panel in the top, and asoft rubber gasket on the periphery of the open bottom4.Thoroughly soap a section of the seam and place the inspectionbox over the soaped seam section and the gasket sealed to theliner. Apply a vacuum between 4 and 8 in. (122 and 244 mm)of
29、 mercury (Hg) to the box by use of a gasoline or electric-driven power vacuum pump apparatus. The applied vacuumwill show bubbles over unbonded areas; the unbonded areascan then be marked for repair.7.4 Ultrasonic (High Frequency) Pulse Echo TestingTestall nonreinforced field seams by passing a high
30、 frequencysound wave through the seam overlap to detect discontinuitiesin the bonded seam. A commercially available frequencygenerator capable of producing frequencies in the range of 5 to15 MHz shall be used. The contact send/receive transducerhead shall be the width of the bonded seam width and sh
31、all becapable of being moved at the rate of 5 to 7 ft/min (1.5 to 2.1m/min) along the surface length of the seam area. Thetransducer head shall be so designed as to give continuoussurface to surface thickness measurements once calibrated.Assure good contact of the test head with the lining surface b
32、yproviding a continuous contact medium (water) at the interfacebetween test head and lining. The ultrasonic signal shall becapable of being viewed on a monitor and capable of triggeringan audible alarm when a discontinuity is detected. Disconti-nuities shall be marked after detection.7.5 Mechanical
33、Point StressingThis test method shall beused as a qualitative measure of edge bonding. A bluntinstrument (for example, a screwdriver) shall be run along theedge of the field seam to find obvious unbonded areas. Theprocedure shall not puncture or otherwise damage the sheetmaterial. Perform point stre
34、ssing only after the seam has hadsufficient time to cure in accordance with manufacturersdirections. This test method is not applicable to all materials,especially those that are easily punctured.8. Report8.1 The report shall include the following:8.1.1 Complete identification of geomembrane system,
35、 in-cluding type of polymer, source, thickness, reinforced ornonreinforced sheeting,8.1.2 Complete identification of field seaming system used,including material, method, temperatures, seam width, curetime, and date of fabrication of field seams,8.1.3 Quality control test or tests used as outlined i
36、n thispractice,8.1.4 Complete description of field sampling procedure,number of test specimens, and size of test specimens,4A vacuum box similar to the Series A 100 Straight Seam Tester as supplied bythe American Parts and Service Company, 2201 West Commonwealth Avenue, P.O.Box 702, Alhambra, CA 918
37、02 has been found satisfactory.D 443728.1.5 Conditioning procedure prior to destructive seamtesting,8.1.6 Type of tensile machine used, grip separation, cross-head speed, grip surface texture, grip dimensions, and grippressure,8.1.7 Method of recording loading and determining averageload for destruc
38、tive test methods,8.1.8 Average, maximum, and minimum peel and shear loadvalues in pounds per inch (kilograms per millimetre) of widthfor individual specimens,8.1.9 Type of failure in the peel and shear tests, that is,within the adhesive system, within the sheet material, clampedge, or seam edge, fo
39、r each individual specimen, and8.1.10 For nondestructive testing, the type of nondestructivetest and number of apparent failures and repairs per 100 ft(30.5 m) of seam.9. Precision and Bias9.1 No statement is made about either the precision or biasof this practice since it merely refers to available
40、 destructiveand nondestructive methods which could be used in determin-ing the quality of bonded seams.The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connectionwith any item mentioned in this standard. Users of this standard
41、are expressly advised that determination of the validity of any suchpatent rights, and the risk of infringement 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 no
42、t revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Headquarters. Your comments will receive careful consideration at a meeting of the responsibletechnical committee, which you may attend
43、. If you feel that your comments have not received a fair hearing you should make yourviews known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM, 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 above address or at610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website (www.astm.org).D 44373
