Laserfiche WebLink
between 400 and 1040 Fahrenheit. <br /> • Verify that ends of extrusion welds that are more than 5 minutes old, are ground to <br /> expose new material before restarting a weld. <br /> • Verify that contact surfaces of the panels are clean, and free of dust,grease,dirt, debris <br /> and moisture before welding. <br /> • Verify that welds are free of dust, rocks and other debris. <br /> • Verify that cross seams are ground to a smooth incline before welding(fusion welding <br /> only). <br /> • Verify that all seams are overlapped a minimum of 3 inches or in accordance with <br /> manufacturer's recommendations, whichever is more stringent. <br /> • Verify that solvents or adhesives are not present in the seam area. <br /> • Verify that procedures used to temporarily hold the panels together do not damage the <br /> panels and do not preclude CQA testing. <br /> • Verify that strips of geomembrane, wide enough and long enough to protect the hot <br /> wedge welder from running on the subgrade is placed below the geomembrane. These <br /> strips may be as long as the seam itself or shorter and moved with the seaming <br /> equipment. If necessary,a firm material such as a flat board or similar hard surface may <br /> be placed directly under the weld overlap to achieve firm support. <br /> • Verify that panels are being welded in accordance with the Construction Drawings and <br /> Specifications. <br /> • Verify that there is no free moisture in the weld area. <br /> • Measure surface temperature of the panels every 2 hours. <br /> 4.2.4 Seam Testing <br /> Nondestructive Seam Testing. The purpose of nondestructive geomembrane testing is to detect <br /> discontinuities or holes in the seams. Nondestructive geomembrane tests include vacuum and air <br /> pressure testing. Nondestructive testing must be performed over the entire length of the seam. <br /> It is the Geosynthetic Contractor's responsibility to perform all nondestructive testing as part of his <br /> quality control(QC)program. The QA/QC Inspector's responsibility is to observe and document that <br /> the Geosynthetic Contractors QC testing is in compliance with the Specifications and to document <br /> Page 25 <br />