Test Equipment: Tests & Capabilities

The TRI Transmissivity Apparatus is equipped with a swing-arm fixture that supports a 50,000 lbf (200 kN) capacity load cell so that it can be moved out of the way between tests. The head loss is measured with both a differential pressure sensor as well as an open manometer. The apparatus is capable of setting hydraulic gradients as high as 1.5 and as low as 0.02.

The TRI Permittivity Apparatus has a touch-screen, digital controller for both constant and falling head tests. The head loss is measured with a high accuracy differential pressure sensor. An electric ball valve is actuated automatically in the Constant Head mode, which causes the collection section to fill with water, resulting in automatic flow rate measurements. The apparatus has a 228-mm (9-inch) diameter upper standpipe device for testing most geotextiles, as well as a 75-mm (3-inch) diameter upper standpipe device for very low flow materials such as slit tape woven geotextiles.

The TRI Capillary Porometer is specially designed for testing geotextiles. The color touch-screen PLC is very technician friendly, making it easy to keep track of which test specimens are complete, and which ones are still in progress. The data is saved in Excel format, suitable to be dropped into the customized Excel report spreadsheets.

The Porometer generates the pore size distribution of woven geotextiles, and can be confidently used for Apparent Opening Size (ASTM D 4751 Method B) and water Permittivity (ASTM D 4491 Method C). The unique specimen “clamshell” type holders prevent the loss of pressure laterally thru the test specimens, and makes the testing process easy to accomplish.

The Porometer is equipped with two separate test cylinders, one dedicated to dry testing only, where the differential pressure across the test specimen facilitates accurate air flow measurements that can be converted to water flow results using R. Lacey’s Characteristic Flow Equation technology. The other test cylinder is used for “wet” tests and for dry air flow testing of geotextiles with low permittivity, where the downstream velocity head is negligible. In the “wet” tests, the test specimens are soaked in the mineral oil wetting fluid and tested to generate the opening size data.

TRI also manufactures stainless steel pneumatically operated ring clamps for both D4833 Puncture and D6241 CBR Puncture tests. Specially designed inserts are available for the CBR Ring Clamp for testing high strength woven geotextiles.