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'1998 GeoSyntcc Consultants TEST PROCED A CONDITIONS TEST SERIES NUMBER: 1 Test Specimen Configuration (from top to bottom) and Placement Conditions: • upper shear box: vegetative soil initially placed at a dry unit weight of 101.6 to 102.2 pcf and a moisture content of 15.5 to 16.5 % for the test series. Final moisture content ranged from 30.3 to 30.7 % for the test series; • Tensar DC4205 geocomposite; and • lower shear box: bedding layer of compacted concrete sand. Test Interfaces: upper soil against geocomposite Test Procedures for Each Normal Stress Condition: • A fresh specimen of concrete sand was compacted into the lower shear box by hand tamping to a relatively dense state under dry conditions forming a 3 in. thick bedding layer. • A fresh specimen of geocomposite was trimmed from the bulk sample and attached to the lower shear box with mechanical compression clamps. • A fresh .specimen of the upper soil was compacted directly on top of the geocomposite specimen. The initial get comMo on conditions (i.e., dry unit weight and moisture content) corresponded to 8umunitweghtand 3 percentage points wet of optim oistent based on the results of a modified Proctor compaction test conduc by GeoSyntec and reported elsewhere. • Soaking Conditions: the entire test specimen was soaked together in tap water for 24 hours under a normal stress of 125 psf. The soaking normal stress was applied prior to immersion. • Test normal stresses: 125, 250, and 350 psf. 4 • Test normal stress was applied within ten minutes of removal of the soaking normal stress and shear commenced immediately after the application of the test normal stress. • Constant shear displacement rate: 0.04 in/min. • The direction of shear for each interface direct shear test was in the direction of manufacture (machine direction) of the Tensar geocomposite sample. • Each test was sheared until a minimum total shear displacement of 2 in. was achieved. WL014U2/SGI98080 1 08.21.98 0