Laserfiche WebLink
INTERFACE DIRECT SHEAR TESTING <br />TEST PROCEDURES AND CONDITIONS <br />TEST SERIES NUMBER: 2 and 3 <br />Test Specimen Configuration (from top to bottom) and Placement Conditions: <br />Test Interface: upper soil against geomembrane against lower soil <br />Test Procedures for Each Normal Stress Condition: <br />• Test normal stress 500 psi. <br />• Constant shear displacement rate: 0.04 in/min. <br />• Shear box size: 6 in. by 6 in. <br />• Each test was sheared until a minimum total shear displacement oft in. was achieved. <br />''2000 GtxtSynlec Consultants <br />• upper shear box: drain cover fill initially placed at a dry unit weight of 112.6 pcf (Test No. 2) and 1 1 2.4 pcf (Test No 3) <br />and a moisture content of 5.0 % (Test No 2) and 5.1 % (Test No. 3). Final moisture content was 12.2% (Test No 2) and <br />11.9 %(Test No. 3), <br />• 80-mil GSE single -sided textured LLDPE geomembrane. with textured side against clay borrow scil liner (SLC-4 ). and <br />• lower shear box: clay borrow soil liner (SLC -4) initially placed at a dry unit weight of 105 4 pcf (Test No. 2) and 105.6 pcf <br />(Test No. 3) and a moisture content of 15.3% (Test No. 2) and 15.1 % (Test No. 3) Final moisture content was 16.1 % <br />(Test No. 2) and 15.8 % (Test No. 3) <br />• A fresh specimen of the clay borrow soil liner (SLC - 4) was compacted into the lower box by hand tamping. The Initial <br />target compaction conditions (i.e., dry unit weight and motsntre content) correspond to 95% of maximum dry unit weight <br />and the optimum moisture based on a standard Proctor compaction test as provided by CC&V. <br />• A fresh specimen of the geomembrane was trimmed from the bulk :ample and was placed such that the textured surface was <br />against the lower soil. The geomembrane was not attached to either the lower or upper shear boxes. With this method of <br />test specimen preparation, shear failure would occur at the w taken interface within the test cross- section. <br />• A fresh specimen of the drain cover fill at its as- recei%ed moisture content was compacted directly on top cf the <br />geomembrane specimen. There was no initial target compaction condition of dry unit weight specified by CC& <br />• Wetting: the drain coy er fill, the geomembrane and the clay borrow soil liner were wetted with tap water prior to shearing. <br />Tap water was poured through the drain cover fill and allowed to drain at the interface between the drain cover 511 and the <br />top of the geomembrane. A fine mist of tap water was also sprayed between the bottom of the geomembrane and the clay <br />borrow soil liner material, on the order of 1.0 to 2.0 oz/yd', prior to the placement of the geomembrane. <br />• Consolidation: For Test No. 3, the entire test cross - section was consolidated for 24 hours under the test normal stress prior <br />to being sheared. <br />GL11126 /SGI00011.DOC 2 00.02.25 <br />