Researches Concerning the Configuration of Geotextiles in the Execution of Regulatory Works in the Riverbeds
Abstract
The paper deals with the behaviour at hydrodynamic action of the geotextiles used in carrying out the regularization and shore defence works located in riverbed. The geotextiles have lately presented applications for the execution of bottom thresholds, of the management dams in riverbed. Also, geotextiles have become an important component in the structure of river defence works on riverbeds. The research was carried out on the lower course of the Moldova River in the area of Pildesti, Neamţ County. The dynamic action of the floods, through the liquid and solid flows, influences the stability and the resistance over time of the constructions made from geotextiles. The researchers analysed the behaviour of the geo-bags made of polyester bags filled with local materials (sand and gravel stabilized with cement), used in the structure of the bottom thresholds, steering dams and in the shore defence works. The research results indicate a differentiated behaviour of the geo-bags depending on the location (in the water, or on the shore) and the mode of action of the water (dynamic or static). The action of the water, through the liquid and solid flow, degraded the structure of the geo-bags by breaking and emptying the filling material. The geo-bags showed a reduced resistance to the action of the alluvial material, especially when the dosage of cement indicated by the design was not achieved. The research highlighted the good behaviour of the geo-bags in the erosion phenomenon of the riverbed, when they were mulched on the erosion zones and ensured the continuity of the constructions in the riverbed (bottom thresholds and shore defences).
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References
[2]. Bica I., Elements of environmental impact, Matrixrom Publishing House, Bucharest, 2000.
[3]. Găzdaru A., Manea S., Feodorov V., Batali L., Geosynthetics in construction, Edit. Romanian Academy, 1999.
[4]. Luca M., Update on rehabilitation technical expertise in the area of under-crossing the river Moldova, Timişeşti water adduction pipes, Soci area, Iasi county, Polias-Instal Iasi Company, 2012.
[5]. Luca M., Tamaşanu F., Luca Al., L., Ilie G., Research on the stability of the defence works to eroded river beds, Ovidius University Annals, Series: Civil Engineering, Issue18, Ovidius University Press, p. 33-41, 2016.
[6]. Luca M., Avram Mihaela, Luca Al. L., Chirica Ştefania, Studies and researches on natural and antropic risk the Moldova’s lower course, PESD, vol. 12, no. 2, “Al. I. Cuza University of Iasi”, p. 183-193, 2018.
[7]. Manoliu I. A., Regulations of rivers and waterways, Ed. Did. and Pedag., Bucharest, 1973.
[8]. Neuhold C., Stanzel P., Nachtnebel H. P., Incorporating river morphological changes to flood risk assessment: uncertainties, methodology and application, Natural Hazards and Earth System Sciences, no. 9, p. 789-799, 2009.
[9]. Romanescu G., Stoleriu C., Causes and Effects of the Catastrophic Flooding on the Siret River (Romania) in July-August 2008, Natural Hazards, 69, p. 1351-1367, 2013.
[10]. Sion P. V., Documentary study on the design, execution and exploitation of the works of river regularization in the concept of "green regularization", Research Report 1, Doctoral School of the Technical University “Gheorghe Asachi” in Iaşi, 2019.
[11]. Ujvari I., The geography of Romania's waters, Edit. Scientific, Bucharest, 1972.
[12]. Vamanu E., Olariu P., Hydroclimatic hazards in the Siret hydrographic area in the context of geographic changes, Collection of papers, Annual Scientific Session INMH Bucharest, 2002.
[13]. ***, Atlas of Water Cadastre in Romania, Ministry of Environment, Bucharest, 1992.
[14]. ***, The geographical Atlas of Romania, Didactic and Pedagogical Publishing House, Bucharest, 1985.
