Investigation of the influence of extreme floods on the stability of protective dams (using the example of Hanoi city)

2019 ◽  
Vol 12 (11-12) ◽  
pp. 26-34 ◽  
Author(s):  
T. H. Dinh ◽  
I. K. Fomenko ◽  
O. E. Vazkova ◽  
O. N. Sirotkina

According to the territorial development plans of the city of Hanoi, there is a need to build a new dam system to ensure the normal functioning of the riverside areas. Therefore, the solution of the problem of analyzing the causes of the loss of stability of the of dam slopes protecting the city from floods is of particular relevance. When assessing the possibility of dam failure as a result of a landslide process, the most important indicator is the appearance of cracks in the body of the dam. The possible mechanisms of loss of stability of the dam slopes as a result of changes in the hydrological situation are considered, their rationale based on the results of mathematical modeling is given. The studies used a “geotechnical” approach to estimating pore pressure values, which is new in Russian practice. This approach, without excluding the need to perform hydrogeological modeling, makes it possible to assess the stability of the dam slopes when the level of flood waters changes. The generalized engineering-geological model of the lithotechnical system (LTS) of the dam can be represented as the following scheme: at the base of the LTS lies an aquifer, represented by sands of various grain sizes and flowing sandy loams, which is overlapped by low-permeable loamy and clayey soils. Two scenarios for the violation of the stability of the dam slope are considered: when the groundwater level rises during the period of extreme flood; due to the rapid drawdown of the level of flood waters. By the methods of mathematical modeling it is proved that the decrease in the stability coefficient occurs in both cases. Thus, it is shown that the collapse of the dam slopes is possible both when the groundwater level rises during the flood period and during a sharp decrease after the end of the flood. At the same time, in the first case there will be a slide of the slopes falling in the direction “from the river”, and in the second — “to the river”. This fact must be taken into account when developing measures to strengthen the slopes of existing dams, as well as when designing a new dam system in Hanoicity.

2021 ◽  
Vol 3 (4) ◽  
pp. 15-23
Author(s):  
Silta Yulan Nifen ◽  
Afif Dzaky Almy

Batang Kuranji is a river located in Kota Padang. The high rainfall and human factors that cause changes in characteristics, especially in the upstream area make the water from the flow of kuranji stems in the rainy season often overflows, and cause flash floods, therefore built Check Dam at the head of the river batang kuranji to prevent the shallowing of the riverbed. Thisresearch aims toreview the structure of the Check Dam 3 building on Batang Kuranji in the city of Padang. This study refers to SNI 2851:2015 with rainfall data for 15 years used from 2005 to 2019, with batu busuk observation station and rice fields obtained from PSDA. Luas DAS is obtained from ArcGIS Applications. Dari hydroligi analysis obtained rainfall plan (R100th) 153,152 m3/dt with Gumbel method, Discharge flood plan for the 100 year anniversary period used Haspers method obtained (Q100th) 165.19 m3/dt. The type of Check Dam that is planned is the type of pelimpah (head work) with a height of Check Dam 8.5 m. Tilt of the body at the upstream 0.6, the distance between the main dam and sub dam 25.2 m, the thickness of the apron floor 1.6 m, with an estimated volume of sediment flow that can be accommodated by 14797.6 m3. The stability of the Check Dam construction was obtained at a value of 3.43 >1.5 and a sliding of 1.53 > 1.5 with a safety coefficient of 1.5, so that the construction of the Check Dam was stable.


1999 ◽  
Vol 386 ◽  
pp. 43-75 ◽  
Author(s):  
V. A. VLADIMIROV ◽  
K. I. ILIN

In this paper we study a dynamical system consisting of a rigid body and an inviscid incompressible fluid. Two general configurations of the system are considered: (a) a rigid body with a cavity completely filled with a fluid and (b) a rigid body surrounded by a fluid. In the first case the fluid is confined to an interior (for the body) domain and in the second case it occupies an exterior domain, which may, in turn, be bounded by some fixed rigid boundary or may extend to infinity. The aim of the paper is twofold: (i) to develop Arnold's technique for the system ‘body + fluid’ and (ii) to obtain sufficient conditions for the stability of steady states of the system. We first establish an energy-type variational principle for an arbitrary steady state of the system. Then we generalize this principle for states that are steady either in translationally moving in some fixed direction or rotating around some fixed axis coordinate system. The second variations of the corresponding functionals are calculated. The general results are applied to a number of particular stability problems. The first is the stability of a steady translational motion of a two-dimensional body in an irrotational flow. Here we have found that (for a quite wide class of bodies) the presence of non-zero circulation about the body does not affect its stability – a result that seems to be new. The second problem concerns the stability of a steady rotation of a force-free rigid body with a cavity containing an ideal fluid. Here we rediscover the stability criterion of Rumyantsev (see Moiseev & Rumyantsev 1965). The complementary problem – when a body is surrounded by a fluid and both body and fluid rotate with constant angular velocity around a fixed axis passing through the centre of mass of the body – is also considered and the corresponding sufficient conditions for stability are obtained.


2019 ◽  
Vol 6 (4) ◽  
Author(s):  
Aleksey Kamenchukov ◽  
Andrey Lopashuk ◽  
Victor Lopashuk ◽  
Victor Svetenok ◽  
Ilya Ukrainskiy

The article considers the issues of assessing and improving the quality and reliability of culverts and the road drainage system on roads with unpaved and transitional types of pavement. The authors performed a number of field studies aimed at assessing the operational condition of culverts and pavement above them on roads of territorial significance in the Khabarovsk Territory. The issues of the influence of the quality of culverts on the condition of the road surface are examined in detail. Systematized and analyzed data on the influence of the presence (absence) of defects in the body of culverts on the quality of the road surface. The data are ranked by the diameter of the pipe hole and the size of the protective layer, and the degree of influence of the quality of the culvert on the quality of the road surface depending on the thickness of the protective layer is determined. The relationship between defects in culverts and the quality of the road surface is established. Based on the result of mathematical modeling, a nomogram of the dependence of the state of the coating over the culvert on the thickness of the backfill over the pipe and the condition of the culvert is constructed. In a specialized software package, by the finite element method, an assessment of the stress-strain state and structural stability of the subgrade with a culvert under the influence of the normative static load on the structure is carried out. The results of mathematical modeling showed that there is a significant decrease in the stability of the structure, especially with low embankments. To increase the stability and reduce the deformation of the structure, the authors proposed a method of strengthening the embankment of the subgrade in places of the device, which on the basis of mathematical modeling showed its high efficiency.


2020 ◽  
Vol 2 (1) ◽  
pp. 32-55
Author(s):  
Natalia Christofoletti Barrenha
Keyword(s):  
The Face ◽  

This text seeks to explore the Argentine films Castro (Alejo Moguillansky, 2009) and El asaltante (Pablo Fendrik, 2007) from within the displacement of their characters through the city. This transit configures the organising element of the plots, determining the direction and rhythm of events. The escape motto will structure the film analyses, which are also twinned by the sensory apprehension that comes from the spaces they travel through. The notion of escape, as explored by Esteban Dipaola in Argentine cinema of the 1990s, continues to throb in mid-to-late 2000s production, and in these films represents the means by which the protagonists deploy critical attitudes—sometimes radical and explosive, sometimes silent—in the face of fixed notions, suggesting some scepticism about the “stability” and “order” that they (dis)encounter in normality. RESUMEN Este texto busca explorar los largometrajes argentinos Castro (Alejo Moguillansky, 2009) y El asaltante (Pablo Fendrik, 2007) a partir del desplazamiento de sus personajes por la ciudad. El transitar se configura como elemento organizador de las tramas, determinando la dirección y el ritmo de los acontecimientos. El tema de la fuga irá estructurando los análisis de las películas, las cuales también están relacionadas por la aprehensión sensorial que hacen de los espacios que recorren. La noción de fuga, tal y como fue explorada por Esteban Dipaola en el cine argentino de los años 90, continúa vigente en la producción de mediados/fines de la primera década del siglo XXI, y en estas películas es el recurso por medio del cual los protagonistas despliegan actitudes críticas – a veces radicales y explosivas, y a veces silenciosas – frente a nociones convencionales, lo cual hace pensar que existe un cierto escepticismo con relación a la “estabilidad” y al “orden” que ellos (des)encuentran en la normalidad. RESUMO Este texto busca explorar os longas-metragens argentinos Castro (Alejo Moguillansky, 2009) e El asaltante (Pablo Fendrik, 2007) a partir do deslocamento de seus personagens pela cidade. O transitar configura-se como elemento organizador das tramas, determinando a direção e o ritmo dos acontecimentos. O mote da fuga estruturará as análises dos filmes, os quais também se irmanam pela apreensão sensorial que fazem dos espaços que percorrem. A noção de fuga, conforme explorada por Esteban Dipaola no cinema argentino da década de 1990, continua a pulsar na produção de meados/fins dos anos 2000, e é, nestes filmes, o recurso através do qual os protagonistas desdobram atitudes críticas – às vezes radicais e explosivas, às vezes silenciosas – diante de noções fixas, sugerindo certo ceticismo em relação à “estabilidade” e à “ordem” que eles (des)encontram na normalidade.


Author(s):  
Valery А. Gruzdev ◽  
◽  
Georgy V. Mosolov ◽  
Ekaterina A. Sabayda ◽  
◽  
...  

In order to determine the possibility of using the method of mathematical modeling for making long-term forecasts of channel deformations of trunk line underwater crossing (TLUC) through water obstacles, a methodology for performing and analyzing the results of mathematical modeling of channel deformations in the TLUC zone across the Kuban River is considered. Within the framework of the work, the following tasks were solved: 1) the format and composition of the initial data necessary for mathematical modeling were determined; 2) the procedure for assigning the boundaries of the computational domain of the model was considered, the computational domain was broken down into the computational grid, the zoning of the computational domain was performed by the value of the roughness coefficient; 3) the analysis of the results of modeling the water flow was carried out without taking the bottom deformations into account, as well as modeling the bottom deformations, the specifics of the verification and calibration calculations were determined to build a reliable mathematical model; 4) considered the possibility of using the method of mathematical modeling to check the stability of the bottom in the area of TLUC in the presence of man-made dumping or protective structure. It has been established that modeling the flow hydraulics and structure of currents, making short-term forecasts of local high-altitude reshaping of the bottom, determining the tendencies of erosion and accumulation of sediments upstream and downstream of protective structures are applicable for predicting channel deformations in the zone of the TLUC. In all these cases, it is mandatory to have materials from engineering-hydro-meteorological and engineering-geological surveys in an amount sufficient to compile a reliable mathematical model.


Author(s):  
Natalia Prodiana Setiawati ◽  
Joko Santoso ◽  
Sri Purwaningsih

The utilization of local food commodities such as corn and cassava with seaweed addition as a dietary fiber source for producing artificial rice through extrusion technology is an  alternative for food diversification. The research was carried out to find out the best composition (rice, corn, cassava, and seaweed) and temperature of extrusion process on making artificial rice and the influence of dietary fibre on sensory properties and physicochemical. The composition of rice, corn, and cassava in proportion  of 1:3:1 with 20% seaweed, Eucheuma cottonii, addition and temperature extruder of 90 °C were selected as the best product for artificial rice. The  sensory evaluation was 8.02±0.21 (people’s preference). In physicochemical properties, dietary fiber significantly affected on low bulk density and starch digestibility. This condition is very good for health especially in maintaining the stability of blood glucose in the body. Keywords: artificial rice, composition, extrusion, seaweed, dietary fibre, temperature


Author(s):  
Fesenko, H.

Purpose. Increasing the uniformity of distribution of mineral fertilizers and other bulk materials due to the stability of their feed from the body to the spreading working bodies using the top feeder. Methods. The following methods are used to achieve this aim: the method of comparing the differences between individual groups of fertilizers, the method of analyzing the properties of a new technical system, the method of functional inventiveness, and the methods of theoretical and analytical mechanics. Results. The traction body of the conveyor of the upper feed of the body fat body machine for mineral fertilizers and other bulk materials was substantiated and the relationship between the height of its scrapers and the distance between them was established, as well as the nature of the mineral fertilizer pressure on the curvilinear wall of the body. In addition, the design of the advanced body fertilizer spreader is justified, which ensures a stable flow of fertilizers from the body due to the improvement of the top feeder. Conclusions. Because of the conducted researches, the advantages of machines equipped with top feeder are found. They create the conditions for the forced feeding mineral fertilizers and other loose materials from the container to the distribution bodies, which is a prerequisite for their evenness on the surface. With this, the imperfection of known machines with the top feeder constrains their introduction into agricultural production. On this account, a more thoroughly constructed solution of the body feeder of the top feed is substantiated, in which the conveyor provides a stable supply of fertilizers from the body with reduced energy consumption during operation. Keywords: analysis, feed, upper device, conveyor, stability, fertilizers, flow ability, body.


2020 ◽  
Vol 14 (2) ◽  
pp. 108-125
Author(s):  
Apoorva Singh ◽  
Nimisha

: Skin cancer, among the various kinds of cancers, is a type that emerges from skin due to the growth of abnormal cells. These cells are capable of spreading and invading the other parts of the body. The occurrence of non-melanoma and melanoma, which are the major types of skin cancers, has increased over the past decades. Exposure to ultraviolet radiations (UV) is the main associative cause of skin cancer. UV exposure can inactivate tumor suppressor genes while activating various oncogenes. The conventional techniques like surgical removal, chemotherapy and radiation therapy lack the potential for targeting cancer cells and harm the normal cells. However, the novel therapeutics show promising improvements in the effectiveness of treatment, survival rates and better quality of life for patients. Different methodologies are involved in the skin cancer therapeutics for delivering the active ingredients to the target sites. Nano carriers are very efficient as they have the ability to improve the stability of drugs and further enhance their penetration into the tumor cells. The recent developments and research in nanotechnology have entitled several targeting and therapeutic agents to be incorporated into nanoparticles for an enhancive treatment of skin cancer. To protect the research works in the field of nanolipoidal systems various patents have been introduced. Some of the patents acknowledge responsive liposomes for specific targeting, nanocarriers for the delivery or co-delivery of chemotherapeutics, nucleic acids as well as photosensitizers. Further recent patents on the novel delivery systems have also been included here.


Author(s):  
A.C.C. Coolen ◽  
A. Annibale ◽  
E.S. Roberts

This chapter reviews graph generation techniques in the context of applications. The first case study is power grids, where proposed strategies to prevent blackouts have been tested on tailored random graphs. The second case study is in social networks. Applications of random graphs to social networks are extremely wide ranging – the particular aspect looked at here is modelling the spread of disease on a social network – and how a particular construction based on projecting from a bipartite graph successfully captures some of the clustering observed in real social networks. The third case study is on null models of food webs, discussing the specific constraints relevant to this application, and the topological features which may contribute to the stability of an ecosystem. The final case study is taken from molecular biology, discussing the importance of unbiased graph sampling when considering if motifs are over-represented in a protein–protein interaction network.


2009 ◽  
Vol 12 (7) ◽  
pp. 953-956 ◽  
Author(s):  
Lynne M Boddy ◽  
Allan F Hackett ◽  
Gareth Stratton

AbstractObjectiveTo estimate the prevalence of underweight between 1998 and 2006 in Liverpool schoolchildren aged 9–10 years using recently published underweight cut-off points.Design and settingStature and body mass data collected at the LiverpoolSportsLinx project’s fitness testing sessions were used to calculate BMI.SubjectsData were available on 26 782 (n13 637 boys, 13 145 girls) participants.ResultsOverall underweight declined in boys from 10·3 % in 1998–1999 to 6·9 % in 2005–2006, and all sub-classifications of underweight declined, in particular grade 3 underweight, with the most recent prevalence being 0·1 %. In girls, the prevalence of underweight declined from 10·8 % in 1998–1999 to 7·5 % in 2005–2006. The prevalence of all grades of underweight was higher in girls than in boys. Underweight showed a fluctuating pattern across all grades over time for boys and girls, and overall prevalence in 2005–2006 represents over 200 children across the city.ConclusionsUnderweight may have reduced slightly from baseline, but remains a substantial problem in Liverpool, with the prevalence of overall underweight being relatively similar to the prevalence of obesity. The present study highlights the requirement for policy makers and funders to consider both ends of the body mass spectrum when fixing priorities in child health.


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