scholarly journals Environmental Impact of Geosynthetics in Coastal Protection

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 634
Author(s):  
Philipp Scholz ◽  
Ieva Putna-Nimane ◽  
Ieva Barda ◽  
Ineta Liepina-Leimane ◽  
Evita Strode ◽  
...  

Geosynthetic materials are applied in measures for coastal protection. Weathering or any damage of constructions, as shown by a field study in Kaliningrad Oblast (Russia), could lead to the littering of the beach or the sea (marine littering) and the discharge of possibly harmful additives into the marine environment. The ageing behavior of a widely used geotextile made of polypropylene was studied by artificial accelerated ageing in water-filled autoclaves at temperatures of 30 to 80 °C and pressures of 10 to 50 bar. Tensile strength tests were used to evaluate the progress of ageing, concluding that temperature rather than pressure was the main factor influencing the ageing of geotextiles. Using a modified Arrhenius equation, it was possible to calculate the half-life for the loss of 50% of the strain, which corresponds to approximately 330 years. Dynamic surface leaching and ecotoxicological tests were performed to determine the possible release of contaminants. No harmful effects on the test organisms were observed.

2020 ◽  
Author(s):  
Julia Gorbunova ◽  
Boris Chubarenko

<p>Beach wrack (BW) – biological marine materials as algae, sea grasses and other, which are thrown from the sea to the seashore, becoming a polluter and cause of inconvenience. Problem of BW is present in the Kaliningrad Oblast of Russia, South-Eastern Baltic. From time to time, large amounts of BW appear in various places along its seashore. However, BW can be used as an organic resource, so nuisance could be converted into resource and asset. The study on BW spatial and quantitative distribution and its potential use in the South-Eastern Baltic is carry out within the Project #R090 CONTRA of the Interreg Baltic Sea Region Programme and accompanied by researches of algae species composition basing on partly support of the State assignment of IO RAS (Theme No. 0149-2019-0013).</p><p>An observations of the Baltic seashore within the Kaliningrad Oblast was carried out in March-December 2019 with the aim of quantity and quality characteristic of BW emissions. The BW emissions were recorded (measured, described and geo-referenced using GPS navigation) and sampled on two model sites monthly and the alongshore survey was carried out seasonally. Monitoring of the time of residence of the BW emissions was carried out three times per day at the selected model site using a web camera. It was found that the distribution of BW was characterized by significant spatial and temporal variability. In general, large amounts of BW emissions were observed on the northern coast of the Sambian Peninsula, in contrast to the western coast and Curonian and Vistula spits. The largest accumulations of BW were local and mainly near the coastline protrusions as capes (natural) and breakwaters, slipways, bunes (man-made). The time of residence of BW storage varied greatly and was often limited to a few days. Their further transformation could be carried out in several ways - by flushing back to the sea, covering under the thickness of sand or small pebbles, and a wind-wave dispersal along the beach. BW mainly contains Radophyta algae in the early spring and autumn-winter periods, in contrast to summer, when there are also Chlorophyta and Phaeophyta.</p><p>The preliminary estimations show that the industrial use of BW is limited by the spatial and temporal irregularity of their emissions in the Kaliningrad Oblast. However, the problem of BW collection and utilization exists. A possible solution could be use of BW for coastal protection greenery as nutrients that is similar to a natural process. These experiments were initiated in the Curonian Spit National Park in 2019. In this way BW could be involved in soft engineering techniques to manage the coastline.</p>


1985 ◽  
Vol 107 (2) ◽  
pp. 167-172 ◽  
Author(s):  
W. F. Weeks

A recent series of tests on the uniaxial compressive strength of ice samples taken from multiyear pressure ridges allows the testing of several hypotheses concerning the variation in strength within and between ridges. The data set consists of 218 strength tests performed at two temperatures (−5° and −20°C) and two strain rates (10−3 and 10−5 s−1). There was no significant difference between the strength of the ice from the ridge sails and the ice from the ridge keels when tested under identical conditions. As the total porosity of the ice from the sails is higher by 40 percent than the ice from the keels, the lack of a significant difference is believed to result from the large variations in the structure of the ice which occur randomly throughout the cores. A three-level analysis of variance model was used to study the variations in strength between 10 different ridges, between cores located side by side in a given ridge, and between samples from the same core. In all cases the main factor contributing to the observed variance was the differences within cores. This is not surprising considering the rather extreme local variability in the structure of ice in such ridges. There was no reason at the 5 percent level of significance to doubt the hypothesis that the different cores at the same site and the different ridges have equal strength means.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Cintya Ap. Christofoletti ◽  
Annelise Francisco ◽  
Carmem S. Fontanetti

A large volume of generated sewage sludge makes its disposal a problem. The usage of sludge in agriculture is highlighted by a number of advantages. However, heavy metals and other toxic compounds may exercise harmful effects to soil organisms. This study evaluated the possible toxic effects of a biosolid sample, under laboratory conditions, for 30 days, using diplopodsRhinocricus padbergiand plantsAllium cepa(onion) as test organisms. The data obtained demonstrated that the biosolid raw sample had genotoxic potential forAllium ceparoot tip cells. In the diplopods exposed to biosolid sample, epithelium disorganization in the midgut and a reduction of the volume of the hepatic cells were observed after 7 days of exposure. After 30 days, the animals still showed a reduction of the volume of the hepatic cells, but in minor intensity.Allium cepaanalysis showed genotoxicity, but this effect was reduced after 30 days of bioprocessing by diplopods. This study was important to know the effects as well as to determine how this waste could be applied concerning the soil living organisms and plants.


2015 ◽  
Vol 1100 ◽  
pp. 211-217
Author(s):  
Bozena Dohnalkova ◽  
Rostislav Drochytka ◽  
Jakub Hodul ◽  
Tomáš Ťažký

The objective of this paper is to examine the solidification possibilities of selected waste in form of industrial waste sludge, within the paper solidification formulas are designed which are subsequently laboratory tested by compressive strength tests after 28 and 60 days, leachability tests and other tests considering environmental impacts – ecotoxicological tests.


2013 ◽  
Vol 743-744 ◽  
pp. 870-877 ◽  
Author(s):  
Jin Ping Wang ◽  
Bo Yuan ◽  
Jian Wang ◽  
Yi Luo

Activation energy is an important parameter which determines thermal stability of solar selective absorbing coating. In this investigation, a new performance criterion (PC) was defined for solar selective coating according to our modified equation of photo-thermal conversion. Then the activation energy of Cu/stainless steel (SS)-AlN/SiAlOxsolar selective absorbing coating was measured. Cu/SS-AlN/SiAlOxtandem films were deposited by magnetron sputtering. Accelerated ageing tests were performed on the coating at 500°C and 550°C, under the atmosphere, calculatingPCfrom the reflectance spectrum and measuring the failure time. According to Arrhenius equation, the activation energy and the equivalent life span of Cu/SS-AlN/SiAlOxtandem film at 400°C were determined to be about 187.4kJ/moland more than 16260 hours, respectively.


1983 ◽  
Vol 28 (1) ◽  
pp. 79-79
Author(s):  
Claire B. Ernhart

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