A new test for water permeability of concrete has been developed. To make a concrete specimen for test, the open end of a rubber-encased foam cylinder is adhered to the center of the inside bottom of a standard 6x12-inch cylinder mold. Fresh concrete is placed in the mold. After 24 hours the mold is stripped and the concrete sample is inverted to expose the open end of the rubber-encased foam cylinder. The operator pours gasoline into this opening. This dissolves the plastic foam so that its thin rubber encasement collapses. This is washed out with water, leaving a smooth symmetrical core. The concrete specimen is placed, open core up, on a layer of washed sand in a 5-gallon pail and leveled. Water is introduced into the pail. At the end of the immersion period, water which has permeated into the core is removed with a pipet and its volume measured.
It has been reported that the test is easy for quality control personnel to perform routinely. Commercially produced test kits are available that supply all of the necessary materials.