Scope:

Under an imposed hydraulic gradient, the ASTM D7760 test method is used to evaluate one-dimensional vertical water flow through initially saturated TDAs (tire derived aggregates). TDAs are used in a variety of civil engineering applications that require hydraulic conductivity. TDAs are evaluated at a unit weight and in a controlled environment. Overburden pressure is a measure of the overburden pressure in the field.

Procedure:

In ASTM D7760, the porous end pieces are soaked in the permeant (water) filled in a container. The permeameter is connected to the pressure application system and the hydraulic system is connected to the incoming and outgoing water. Under a partial vacuum applied to the top of the specimen, the specimen is inundated with the permeant (water). At least three hydraulic gradients are used to penetrate the specimen. The required overburden pressure to the specimen is applied. The constant-head hydraulic system is set up. The influent valves are opened. The time at which each permeation trial began and ended is measured.

video 01: Hydraulic conductivity

Result:
The results obtained in ASTM D7760 testing are computed as hydraulic conductivity in cm/s or other units to two or more significant digits.

Conclusion:

Under an imposed hydraulic gradient, the ASTM D7760 test method is used to evaluate one-dimensional vertical water flow through initially saturated TDAs (tire derived aggregates).