Recent material development has seen geosynthetics dominate many civil engineering works owing to the suitable attributes they possess, namely: ease of application, economical, low environmental impact and high efficiency. These polymeric materials are of utmost importance and of much interest when it comes to coastal developments such as dykes, jetties, groynes, artificial reefs and seawalls. Such torturous outdoor applications demand rigorous material testing. Durability testing of geosynthetics in in-situ conditions is normally time consuming and unsuitable when quick results are needed. Nonetheless, since the tests are carried out under real degradation conditions, they provide reliable and accurate information regarding the durability of geosynthetics. Unfortunately, despite the widespread utilization of geosynthetics in coastal engineering structures, very few papers have been published in relation to their degradation in marine environments.
To this note, University of Porto researchers (José Ricardo Carneiro, Miguel Morais and Maria de Lurdes Lopes) evaluated the resistance of three nonwoven polypropylene (PP) geotextiles with different stabilization packages against seawater, weathering and action of tides. They aimed at determining the effects of the various degrading agents in relation to the physical and mechanical properties of the geotextiles. In addition, they evaluated the effects of the stabilization package in the degradation suffered by the geotextiles. Their work is currently published in the research journal, Construction and Building Materials.
The research work as undertaken entailed the exposure of three nonwoven PP geotextiles with different stabilization packages to seawater, weathering and action of tides in inherent marine conditions. The exposures were carried out in Portugal for a period of 36 months.
The authors observed that weathering contributed to the highest damage in the geotextiles. Additionally, they noted that the weathering resistance of the geotextiles was highly enhanced by Chimassorb 944 and carbon black (two chemical additives). Moreover, it was also seen that the geotextiles had a good resistance against the action of seawater. Lastly, the research team recorded that algae and dirt that accumulated in the nonwoven structures during the exposure to the action of tides, guarded the geotextiles from UV-degradation.
In summary, their study presented an in-depth assessment of the behavior of PP geotextiles in marine environments. Generally, they observed that based on the outdoor degradation tests undertaken, some notable changes in the physical and mechanical properties of three nonwoven geotextiles were revealed. Furthermore, the deterioration of the physical and mechanical properties of the geotextiles during the exposure to weathering were mainly attributed to the damaging effects of UV radiation. Altogether, the PP geotextiles present a quite good resistance against the action of seawater.
José Ricardo Carneiro, Miguel Morais, Maria de Lurdes Lopes. Degradation of polypropylene geotextiles with different chemical stabilizations in marine environments. Construction and Building Materials, volume 165 (2018) page 877–886.Go To Construction and Building Materials