ASTM D5885 Standard Test Method for Low Strain Impact Integrity Testing of Deep Foundations

Get Certified ASTM D5885 Testing for Reliable Geosynthetic Stabilization Performance 

Certification verifies the conformance of a polyolefin geosynthetic to the ASTM D5885 specification, including OIT at set oxygen pressure and temperature. Before accepting a geomembrane or geosynthetic product for use in a landfill liner or containment system, or any other geosynthetic application, it undergoes an antioxidant stabilization test according to ASTM D5885 specifications. Testing and certification ensure compliance with ASTM D5885 criteria and reduce the risk of an early breakdown caused by oxidative degradation. 

The scope of ASTM D5885  includes:

• Material type: Polyolefin geosynthetics such as geomembranes, geogrids, geonets, and geotextiles. 
• Purpose: The purpose is to quantify for the evaluation of oxidative induction time and antioxidant stabilization. 
• Properties evaluated: Oxidative induction time (OIT). 
• Testing Method: Testing involves pressurizing a specimen disk in an oxygen-filled D.S.C. cell and heating to the isothermal test condition. 
• Result: The oxidative induction time is reported in minutes at the specified test temperature and pressure. 
• Test Limitations: he test standard is applicable to materials with an OIT > 30 minutes when tested at 3.4 MPa of oxygen at 150°C, and the results do not directly reflect the service life of a geomembrane. 
• Use conditions: Oxygen pressure and isothermal test temperature significantly affect the measured oxidative induction time. 
• Applications: Landfill liner and containment system quality control, geomembrane formulation comparison, geosynthetic supplier verification, antioxidant stabilization monitoring. 

What are the Uses of ASTM D5885 Testing?

ASTM D5885 testing is used to evaluate the antioxidant stabilization of polyolefin geosynthetic materials when exposed to accelerated oxidative conditions. Engineers use the results to compare formulations and to understand the oxidative resistance of a geosynthetic. This standard-

• Assesses the oxidative induction time of polyolefin geosynthetics.
• Enhances oxidative degradation artificially by increasing the pressure of oxygen.
• Assesses antioxidant stabilization as received from a supplier.
• Helps to compare the various geomembrane formulations at a given test temperature.
• Aids in quality control monitoring of geosynthetic stabilization.
• Assists in product development and formulation verification.
• Helps in the selection of antioxidant packages for geosynthetic products.

What Materials Can Be Tested Under ASTM D5885? 

ASTM D5885 is used for polyolefin geosynthetics such as geomembranes, geogrids, geonets, and geotextiles, and is most commonly used for geomembranes. Common materials are geomembranes for landfill liners and polymembranes for containment applications, e.g., polyethylene, polypropylene. Analysts select a small specimen disc cut from the geosynthetic sample for testing. 

Why is ASTM D5885 Important? 

ASTM D5885 is a standard, accelerated method to determine the antioxidant stabilization added to a geosynthetic made from a polyolefin. Manufacturers and/or specifiers use this measured oxidative induction time as a quality control measurement, but the standard clarifies that the OIT value should not be used to predict the geomembrane’s actual service life. 

ASTM D5885 Testing Process and Data Collection

Testing starts once the technician cuts and weighs a specimen disc from the polyolefin geosynthetic sample and puts it in an open aluminum pan. The technician then places the pan inside the differential scanning calorimetry cell and pressurizes the cell with oxygen to the desired test pressure. The instrument heats the specimen to the isothermal test temperature and maintains it at that temperature, measuring the heat flow continuously. The instrument senses the onset of an exothermic oxidation reaction and records the duration of the reaction. Finally, the analyst records this elapsed time as the oxidative induction time of the specimen under the given pressure and temperature conditions. 

Common Challenges and Troubleshooting

The pressure inside the cell varies from time to time, which results in inconsistent oxygen pressure readings of the OIT, as the pressure directly affects the rate of oxidative acceleration. The measured induction time may also vary from one disk to another due to mass or thickness variation of the specimen unless these parameters are kept constant across the comparison. The isothermal hold period could cause a distortion of the onset detection of the exothermic reaction. Laboratories solve these problems by using a pressure calibration verification for the oxygen pressure, by preparing samples with uniform mass, and by maintaining uniform isothermal temperature control. 

• The laboratory measures the oxidative induction time in minutes under the specified oxygen pressure and isothermal temperature.
• The technician will identify the type(s) of geosynthetic(s) being tested, whether that be geomembrane, geogrid, geonet, or geotextile.
• The analyst notes the induction time obtained under the aforementioned pressure and temperature conditions and correlates the value with the antioxidant formulation of the tested material.
• The engineer takes into account the test temperature, the oxygen pressure, and the type of resin when analyzing the results of oxidative induction time.
• Engineers use the measured oxidative induction time values to support quality control and formulation comparison for polyolefin geosynthetics. 

Link to ASTM D5885