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Section 02776 <br />Geomembrane <br />amec <br />2. If the seam cannot be tested prior to final installation, the seaming operations shall be <br />observed by CQA Monitor for uniformity and completeness. <br />E. In the event that seam continuity cannot be demonstrated for a non - destructive test of a fusion <br />seam as outlined above, the CONTRACTOR shall perform the non - destructive testing over <br />smaller areas as a means of defining the questionable area. The identified questionable area shall <br />be capped. Flap welding is not an acceptable method of repairing a failed seam length. <br />3.09 DESTRUCTIVE TESTING <br />A. CONTRACTOR shall test a minimum of one destructive test sample per five hundred (500) feet <br />of seam length from a location specified by CERTIFYING ENGINEER. CONTRACTOR <br />shall not be informed in advance of the sample location. The samples shall be taken centered over <br />the seam and prioritized as follows: <br />1. A minimum of one sample per day; <br />2. All areas identified as suspect during seaming, non - destructive testing /monitoring, and in <br />unusual working conditions. <br />3. A minimum of one sample for each geomembrane seamer. <br />4. A minimum of one sample every five hundred (500) feet of seaming. <br />B. Samples shall be cut by CONTRACTOR as the seaming progresses. Sampling locations shall be <br />determined by CERTIFYING ENGINEER. CQA Monitor must witness the obtainment of all <br />destructive test samples by CONTRACTOR. CONTRACTOR shall mark all samples with their <br />seam number, date, welding machine number, welding technician identification, extruder and <br />nozzle /wedge temperature, and ambient air temperature. CONTRACTOR shall document the <br />date, time, roll and seam number, ambient temperature, and pass or fail description. All holes in <br />the geomembrane resulting from obtaining the seam samples shall be immediately repaired. All <br />patches shall be vacuum tested. <br />C. The samples shall be a minimum twelve (12) inches wide by twenty-four (24) inches long with the <br />seam centered lengthwise. The sample shall be cut into two equal length pieces, half to be given <br />to CC &V and the other half kept by CONTRACTOR. <br />D. CONTRACTOR shall cut and test ten (10) one (1) inch wide specimens from his sample. All <br />testing shall be conducted at room temperature (60° F - 80° F) CONTRACTOR shall test five <br />(5) specimens for seam shear strength and five (5) for peel strength. Both inside and outside <br />tracks of fusion seams will be tested for peel strength. To be acceptable, four (4) out of the five <br />(5) specimens must pass according to criteria established in Article 2.01. Any specimen that fails <br />through the weld or at the weld/sheet interface shall be considered a failure, unless the weld <br />strength exceeds the sheet strength, as discussed in Section 2776, Item 2.01. The tensiometer <br />shall have a grip separation of four (4) inches plus the width of the seam. The seam is to be <br />centered between the clamps. The grip separation rates for LLDPE are twenty (20) inches per <br />minute for shear and twenty (20) inches per minute for peel. These tests shall not fail according to <br />the criteria in Article 2.01. <br />E. CQA Monitor must witness the testing of all destructive samples. Destructive tests will be <br />performed within two (2) days of the samples being obtained. <br />Page 19 of 22 <br />June 19, 2012 <br />Revision 1 <br />