Research of hydrodynamic effect of the water flow on the geosynthetic protective blanket

• Main Authors: Kozlov Konstantin Dmitrievich, Khanov Nartmir Vladimirovich, Fartukov Vasiliy Aleksandrovich, ozlov Dmitriy Vyacheslavovich
• Format: Article
• Language: English
• Published: Moscow State University of Civil Engineering (MGSU) 2018-03-01
• Series: Stroitel’stvo: Nauka i Obrazovanie
• Subjects: Enkamat A20 geomat; hydraulic flume; channel; underwater gradient; rate of slope; section of channel; working section of channel; flow rates; hydrodynamic pressure
• Online Access: http://www.nso-journal.ru/public/journals/1/issues/2018/01/09_01_2018.pdf

Subject of research: In recent domestic practice of hydrotechnical, transport and environment-oriented construction, a semi-synthetic material — Enkamat A20 geomat (Enkamat) — has been widely used in recent years. The carpet from the geomat, filled with crushed stone with bituminous binding material, is used in the constructions of drainage structures and culverts to protect various types of soils (sandy, loamy and clay), as well as to prevent the destructive erosivity of the flowing water on the protected surfaces. The studying of the influence of the hydrodynamic effect of the water flow and the estimation of presence and absence of tearaway loads caused by a shift of flow pressure phases on the upper and lower geomat surfaces became the subject of the researches that were carried out. Objectives: the research program was focused on the quantitative and qualitative assessment of the hydrodynamic effect of the flow passing through the experimental stretch of the conveying channel for the condition and stability of the protective blanket of Enkamat А20 geosynthetic material. Materials and techniques: a series of physical experiments was performed, which made it possible to estimate the effect of the water flow on geosynthetic material. The results of the experimental measurements were processed and analyzed with the use of modern software. Results: in the process of the performed researches, the values of the flow pressure pulsations on the slope and the bottom of the conveying channel were determined at several values of the passing water flow rate, as well as the values water flow pressure pulsations under the protective geosynthetic blanket were determined. Findings: on the basis of the physical experiment, the differences in flow pressures on the surface of the geomat blanket — the upper surface that is in contact with the water flow, and on the lower surface that is in contact with the soil were obtained. The absence of tearaway loads on the lower surface of the blanket, which is in contact with the soil, was identified. Possible demonstrations of tearaway loads associated with the shift of water flow pressure phases on the upper and lower geomat surfaces are shown.