Comparative life cycle assessment of geosynthetics versus conventional filter layer

Paper in proceeding, 2013

Geosynthetics made from plastics can replace filter layers made of gravel. In this article goal and scope, basic data and the results of a comparative life cycle assessment of gravel and geosynthetics based filter layers are described. The filter layers of a road made of 30 cm gravel and a filter geosynthetic, respectively, form the basis for the comparison. The filter layers have the same technical performance and the same life time of 30 years. The product system includes the supply of the raw materials, the manufacture of the geotextiles and the extraction of mineral resources, the construction of the road filter, its use and its end of life phase. The life cycle assessment reveals that the geosynthetics based filter layer causes lower environmental impacts per square metre. The cumulative greenhouse gas emissions amount to 7.8 kg CO2-eq (mineral filter) and to 0.81 kg CO2-eq (geosynthetic filter). The variation of the thickness of the gravel based filter layer confirms the lower environmental impacts of a geosynthetics based filter layer. Environmental impacts of the geosynthetic production are dominated by the raw material provision (plastic granulate) and electricity consumption during manufacturing.