TY - CONF A1 - Müller, Werner A1 - Wöhlecke, Andreas ED - Hsuan, Y. G. ED - Bhatia, S. K. ED - Soong, T. Y. T1 - A study on high oxygen pressure autoclave testing for the oxidative resistance of polyolefin-based geosynthetics T2 - Proceedings of Geo-Chicago 2016 N2 - Testing of the oxidative resistance of polyolefin based geosynthetics in autoclaves at high oxygen pressure has been suggested as an alternative method to conventional forced-air oven aging. The intention is to shorten considerably the testing time and to ensure that aging is performed under the condition of rate-controlled and not diffusion-limited oxidation. We compare data from high pressure autoclave tests (HPAT) with data from oven aging and water immersion tests at 80 °C. For this, the stabilization of the samples has to be taken into account. Polyolefin based geosynthetics are usually stabilized by two types of “packages” of antioxidants (AO), designated here as P1 and P2. P1 consists of phenols and phosphites, P2 of hindered amine stabilizers (HAS) in addition to a marginal stabilization P1 of the resin for the manufacturing process. Phenolic and phosphite AO are quickly consumed in the HPAT. Failure time is tremendously reduced compared to forced-air oven aging or water immersion. The results are discussed within the framework of a basic autoxidation scheme (Wise et al., 1997). The reduction is much greater than expected from theoretical considerations. Therefore, a direct and degrading reaction of oxygen with the AO has to be assumed. In case of HAS, the time dependence of the degradation of tensile properties in the HPAT is significantly different from the dependence observed in conventional forced-air oven aging and their effectiveness is likewise strongly reduced. A conclusive interpretation of HPAT results needs a better understanding of what happens to the AO at high oxygen pressure. T2 - Geo-Chicago 2016 CY - Chicago, IL, USA DA - 14.08.2016 KW - Oxidative resistance KW - Geosynthetics KW - Autocalve testing PY - 2016 UR - http://ascelibrary.org/doi/book/10.1061/geochicago2016 DO - https://doi.org/10.1061/9780784480182.030 VL - Geosynthetics, Forging a Path to Bona Fide Engineering Materials, GSP 275 SP - 332 EP - 341 PB - ASCE CY - Reston, USA AN - OPUS4-37412 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -