Volume 25, Issue 2 (June 2002)
Sidewall Leakage in Hydraulic Conductivity Testing of Asphalt Concrete Specimens
Asphalt specimens with irregular sidewalls can require special testing considerations when measuring hydraulic conductivity in a flexible wall permeameter. The hydraulic conductivity of laboratory prepared, dense asphalt concrete with high asphalt cement content (6–8.5% asphalt cement) was measured in the laboratory. Hydraulic conductivities were found to be excessive and were shown to be caused by sidewall leakage. Applying a thin layer of silicone vacuum grease to the sides of the asphalt specimens arrested the sidewall leakage, thereby permitting more accurate measurement of the hydraulic conductivity of the asphalt concrete.