5.1 Due to hydraulic pressure that may be present on some applications, engineers need to understand the capability of these products to resist this pressure. This test allows engineers to compare products and verify pullout strength.

5.2 Hydraulic pullout resistance is a function of locking extension dimensions, locking extension geometry, locking extensions per area, locking extension polymer composition, and the properties of the concrete in which the locking extensions are embedded.

5.3 The data from this test method provides comparative information for rating hydraulic pullout resistance of different geomembranes with locking extensions embedded in concrete. Hydraulic pullout resistance, while partly dependent on locking extension dimensions, has no simple correlation to locking extension dimensions and geometry. Hence, hydraulic pullout resistance cannot be determined with a small sample without potentially producing misleading data to the actual hydraulic pullout resistance of the material. Therefore, the hydraulic pullout resistance is expressed in kPa (lbs/ft²).

5.4 The apparatus can be circular or square in nature must have a test area of 0.36 m² (558 in.²).

5.5 Fig. 1 shows an example of a circular test apparatus that can be used in the performance of this test. The apparatus requires a pressure vessel rated to a minimum 690 kPa (14 410 lbs/ft²). The vessel test diameter should be a minimum of 677.04 mm (26.655 in.) as shown in Fig. 1.

FIG. 1 Picture of Circular test apparatusNote 1-Larger vessels may be used but it is up to user to establish correlation to the standard size vessel. The use of a smaller diameter vessel than denoted in standard may contribute to higher pullout resistance due to thickness or stiffness of some products.

5.6 Test Pedestal-the base of the testing apparatus which holds the test specimen.

5.7 Upper Flange-is the flange that is bolted down on top of specimen to create a seal.

5.8 Form-is an aluminum ring used to form test specimen as shown in Fig. 2.

FIG. 2 Bottom of Form with Studs facing up and cylinder spacer

5.9 Specimen Ring-the solid ring that is placed around test specimen to contain leakage through the concrete.

5.10 The vessel will have a system to measure pressure.

5.10.1 The system for measuring pressure shall be capable of being read to an accuracy of 3.5 kPa (0.5 psi).

5.11 Concrete shall be a ready-mixed concrete per Specification C94 with a minimum cured compressive strength of 34 473.8 kPa (5 000 psi).

Note 2-Alternate concrete or grout mixtures may be used for project specific applications with the approval of the owner or engineer.

5.12 All tests shall be conducted at standard laboratory temperatures of 23 ± 2°C (73.4 ± 3.6°F).