ARCHIVED REPORTS_2012_1 - Laserfiche WebLink

Home Browse Search

The installer must remove specimens identified by the CQA monitor and then test the specimens for peel and shear. During sampling the CQA monitor must: e Observe sample cutting. e Mark each specimen with an identifying number and record the seam number, welder, weld date and weld time relative to the specimen number. e Record specimen locations on the panel layout drawing and panel-seam logs. e Record the specimen locations,weather conditions,and reason specimens were taken(e.g., random specimen,visual appearance,result of a previous failure, etc.). The Installer must test seam specimens at the project site using a tensiometer capable of quantitatively measuring shear and peel strengths in accordance with ASTM D4437. For double wedge welding both sides of the air channel must be tested for peel strength. The CQA monitor must observe the tests. A specimen passes when the break is a ductile FTB. An FTB means the test specimen breaks at the edge or the outside of the seam, but not in the seam. In addition, the seam strength must meet specified values. If any of the specimens fail to meet specified seam quality, the Installer can, at his discretion, reconstruct the entire seam, or take another test sample ten feet towards the other end of the seam from the point of the failed specimen. At that point the installer can repeat the field peel and shear tests. If subsequent specimens fail to meet specified seam quality, this procedure must be repeated until the length of poor quality seam is established. Repeated failures indicate that the seaming equipment or operator is not performing properly, and appropriate corrective action must be taken immediately. In the case of butt seams, if the peel tests fail,the entire butt seam must be capped. ' All seams must be bounded by specimens from which passing peel and shear tests have been documented. In the case of butt seams, one passing peel test is required in either the original weld or the cap seam. 5.2.11 Repairs Repairs are required where geomembrane panels and or seems contain a flaw where a destructive test sample has been taken and where a "T" intersection exists at corners of welded panels. All of these repairs must be made in accordance with the technical specifications. The CQA monitor must locate required repairs and record completion of repair work on a repair log. Acceptable repair techniques include the following: ' e Patching — used to repair large holes, tears, large panel defects, undispersed raw materials, welds, contamination by foreign matter, destructive sample locations, and "T" locations in panel welds. e Extrusion — used to repair small defects in the panels and seams. In general, this procedure should be used for defects less than'/2-inch in the largest dimension. CH CQA Plan 041712 Rev2a.doc5-1 O Construction Quality Assurance Plan