MEASURES TO ENSURE THE SAFETY AND OPERATIONAL RELIABILITY OF THE FUNCTIONING OF IRRIGATION AND DRAINAGE SYSTEMS WITH A LONG SERVICE LIFE

2021 ◽  
pp. 79-88
Author(s):  
V. B. ZHEZMER ◽  
◽  
A. O. SHCHERBAKOV
Keyword(s):  
Service Life ◽  
Operational Reliability ◽  
Throughput Capacity ◽  
Hydraulic Structures ◽  
Drainage Systems ◽  
Depression Curve ◽  
Average Wear ◽  
Design Values ◽  
High Degree ◽  
Upper Slope

The issues of ensuring the safety and operational reliability of the functioning of irrigation and drainage systems with a long service life are considered. It has been established that the service life of irrigation and drainage systems in the south of Russia is about 40-50 years, the average wear is 72%. In the Krasnodar territory the rate of wear of reservoirs, ponds and canals is about 80-100% which indicates to a signifi cant siltation and loss of throughput capacity. Depreciation of dams and dikes is 35-40%. The main damages of the HTS are erosion of the upper slope, malfunction of the spillway and silting of the reservoir bowl (pond) which leads to increased filtration through the dam body, an increase in the level of the depression curve and complication of the passage of fl ood water. Changes in the rules for the operation of hydraulic structures, in particular, a decrease in the normal retaining level in comparison with the design level is not a rare occurrence. At the same time, the HTS operation in the sparing mode can be considered a temporary measure used until repair or reconstruction is carried out. The operational efficiency of hydraulic structures with a high degree of wear at the level of ultimate loads and impacts below the design values is noticeably getting reduced. The use of constant monitoring, as well as forecasting the reliability of hydraulic structures, can reduce the severity of the problem. Safe and effi cient operation of hydraulic structures with a high degree of wear during the period preceding repair or reconstruction can be ensured by introducing a system for automated monitoring of hydraulic structures in combination with a decision support system (DSS).

LEGAL REGULATION IN THE IMPLEMENTATION OF A SET OF MEASURES AIMED AT ENSURING THE OPERATIONAL RELIABILITY AND SAFETY OF OWNERLESS HYDRAULIC STRUCTURES

2020 ◽  
Vol 3 (82) ◽  
pp. 81-88
Author(s):  
Z.M. Kadiev ◽  
◽  
A.N. Kochetov ◽  
Keyword(s):  
Legal Regulation ◽  
Operational Reliability ◽  
Hydraulic Structures

На территориях, поднадзорных Федеральной службе по экологическому, технологическому и атомному надзору, территориальными Управлениями в рамках возложенных полномочий, проводятся регулярные работы, направленные на выявление и сокращение количества бесхозяйных гидротехнических сооружений. Статус гидротехнического сооружения в качестве бесхозяйного, являющегося объектом, создающими повышенную опасность для населения, требует принятия незамедлительных мер по постановке их на учет и передаче в собственность и/или оперативное управление эксплуатирующей организации для обеспечения безопасности с целью предотвращения чрезвычайных ситуаций и стихийных бедствий. Законодатель уделил особое внимание вопросу соблюдения обязательных требований безопасности бесхозяйных ГТС. И отнес их к наиболее вероятно опасным объектам хозяйственного права. Отсутствие собственника и/или эксплуатирующей организации, подготовленного и аттестованного штата обслуживающих сооружения специалистов, не может не отразиться на потенциальной опасности самого сооружения и, как следствие, территории его расположения. Эти события могут послужить причиной возникновения ситуаций, влекущих за собой негативные последствия, ввиду наличия опасности для жизни и здоровья людей, проживающих на данной территории.

MPACT OF SHOCK WAVES IN INERT MEDIA ON THE OPERATIONAL RELIABILITY OF LOW-PRESSURE EARTH DAMS

2021 ◽  
pp. 52-57
Author(s):  
E. V. ANDREEV ◽  
Keyword(s):  
Gas Dynamics ◽  
Degrees Of Freedom ◽  
Room Temperature ◽  
Hydraulic Structure ◽  
Operational Reliability ◽  
The Body ◽  
Hydraulic Structures ◽  
Safety And Reliability ◽  
Gas Molecules ◽  
Internal Degrees Of Freedom

During the operation of pressure hydraulic structures, there is an objective need to ensure their safety and reliability. In the case of non-stationary loads on hydraulic structures, they can be either seriously damaged or destroyed. One of the non-stationary effects can be considered a directed explosion on the body of a hydraulic structure or in the immediate vicinity of it. At significant Mach numbers, the processes of excitation of the internal degrees of freedom of molecules, ionization and dissociation of gas molecules, and their recombination occur behind the shock wave front. The course of these processes is due to the almost tenfold compression of the gas at the time of the explosion and it’s heating relative to the room temperature of the order of 104 K. The use of approximate and numerical methods is a consequence of the difficulties associated with the need to solve nonlinear equations of gas dynamics, with the simultaneous use of relaxation equations and equations of chemical kinetics at the same time.

scholarly journals Coordinating influence of multilayer graphene and spherical SnAgCu for improving tribological properties of a 20CrMnTi material

RSC Advances ◽  
2018 ◽  
Vol 8 (25) ◽  
pp. 14129-14137 ◽  
Author(s):  
Xiaoxue Li ◽  
Jingli Xu
Keyword(s):  
Service Life ◽  
Tribological Properties ◽  
Friction And Wear ◽  
Wear Behavior ◽  
Operational Reliability ◽  
Multilayer Graphene ◽  
Friction And Wear Behavior

In order to increase the service life and operational reliability of a 20CrMnTi-steel-based gearing system, the friction and wear behavior of 20CrMnTi needs to be further improved.

scholarly journals Sedimentation monitoring including uncertainty analysis in complex floodplains: a case study in the Mekong Delta

2013 ◽  
Vol 17 (8) ◽  
pp. 3039-3057 ◽  
Author(s):  
N. V. Manh ◽  
B. Merz ◽  
H. Apel
Keyword(s):  
Measurement Errors ◽  
Large Scale ◽  
Mekong Delta ◽  
Sediment Traps ◽  
Sediment Deposition ◽  
Hydraulic Structures ◽  
Suspended Sediment Transport ◽  
Monitoring Point ◽  
Sampling Procedures ◽  
High Degree

Abstract. Quantity and quality of sediment deposition in complex floodplains are affected by many processes that are typically highly spatially and temporally variable and hard to quantify exactly. The main processes in this context are suspended sediment transport dynamics in rivers, floodplain channel interactions, and internal floodplain processes. In consequence, any point measurement of sedimentation in floodplains contains a high degree of uncertainty, both stemming from measurement errors and from the lack of representativeness for a larger area. However, up to now, uncertainty analyses have not been performed as part of publications on floodplain sedimentation data. Therefore the present work illustrates a field sampling strategy aiming at the monitoring of floodplain deposition and spatial variability on a large scale and at the quantification of uncertainties associated to sediment deposition data. The study was performed in the Mekong Delta, being an example for a large and complex floodplain with a high degree of anthropogenic disturbances. We present a procedure for the quantification of the uncertainty associated to the data, based on the design of the monitoring campaign, sampling procedures, and floodplain characteristics. Sediment traps were distributed strategically over the floodplain in clusters of three mat traps representing one monitoring point. The uncertainty originating from collection of the traps from still ponding water is quantified by lab experiments. The overall uncertainty of the deposition samples and the associated nutrient content is quantified in a Monte Carlo simulation and illustrated by uncertainty bounds. For the study area the results show a very high variability of the annual floodplain deposition (2.2–60 kg m−2) with uncertainty bounds ranging from −61 to +129% relative to overall mean deposition of 11.4 kg m−2. No correlations in the spatial distribution of sedimentation in the floodplains could be found. This is caused by the highly complex channel and dike system and the high number of hydraulic structures. Also, no differences in deposition between floodplain compartments protected with high and low dikes could be detected. However, it can be shown that within single floodplain compartments the spatial deposition variability depends on the dike levels and operation and location of hydraulic structures.

Ways to increase the service life of metal members of hydraulic structures

1990 ◽  
Vol 24 (1) ◽  
pp. 41-43
Author(s):  
B. Yu. Aivazov ◽  
M. S. Trifel' ◽  
G. M. Akhmedov
Keyword(s):  
Service Life ◽  
Hydraulic Structures

scholarly journals And probabilistic model to calculate on-the-dejnosti nodes and interfaces of the manipulator

2017 ◽  
Author(s):  
Н.А. Сидоренков ◽  
Б.Г. Мартынов
Keyword(s):  
Service Life ◽  
Operational Reliability ◽  
Technical Condition ◽  
Optimal Frequency ◽  
Maintenance And Repair ◽  
Reliability Models ◽  
Warranty Period ◽  
Hydraulic Manipulators ◽  
Statistical Studies ◽  
Proactive Maintenance

Во время эксплуатации гидроманипуляторов (ГМ) возникает задача продления жизненного цикла ГМ. В настоящее время он составляет при полной нагрузке ГМ от 3 до 5 лет или 6000 моточасов до капитального ремонта. В зависимости от условий работы и обслуживания этот ресурс, по данным ПО «Подъемные машины», может быть израсходован за 8 мес. Руководством по эксплуатации ГМ определены пять видов ТО: ЕТО и четыре номерных. Причем в гарантийных обязательствах определен период работы ГМ до первого отказа. Он соответствует примерно 120 моточасам. Для продления срока службы ГМ до капитального ремонта необходимо перейти от обычной планово-предупредительной системы ТО и ремонта к проактивной системе. Основу проактивной системы ТО и Р составляет правильное управление техническим состоянием механизма с целью повышения его эксплуатационной надежности, определения оптимальной периодичности ТО и Р, что в свою очередь требует полной информации о техническом состоянии механизма и надежности его узлов и сопряжений. Цель проактивной системы ТО и Р – предупреждать отказ узлов и сопряжений механизма. Для реализации этой цели необходима разработка модели надежности ГМ и проведение статистических исследований отказов элементов механизма. Поэтому данная задача является актуальной. В настоящей статье приводится выражение, которое позволит формировать стратегию обслуживания данного типа манипуляторов для продления их срока службы. Цель исследования – разработка вероятностной модели надежности узлов и сопряжений ГМ для решения одной из задач управления техническим состоянием механизма с целью обоснования проактивной системы ТО и Р. During operation of hydraulic manipulators (GM), there arises the problem of extending the life cycle of the GM. Currently, it is under full load UM from 3 to 5 years or 6000 hours before overhaul. Depending on the conditions of operation and maintenance of this resource, according to «Lifting machines», can be used for 8 months. The user manual for the GM identifies five kinds: UTB and four plates. And in a warranty period defined by the work of the GM until the first failure. It corresponds to about 120 hours. To extend the service life of the GM overhaul need to move from conventional preventive system of maintenance and repair to a proactive system. The basis for proactive maintenance and R is the correct management of the technical condition of the mechanism with the purpose of increasing its ex-operational reliability, determining the optimal frequency and R, which in turn requires full information about the technical condition of the mechanism and reliability of its components and interfaces. The purpose of proactive maintenance and repair – to prevent failure of the nodes and interfaces of the mechanism. To achieve this goal it is necessary to develop reliability models of the GM and carrying out statistical studies of failures of elements of the mechanism. Therefore, this task is urgent. In this paper, we provide an expression that will form the servicing strategy for this type of manipulators to extend their service life. The purpose of the study: the development of probabilistic reliability models of the nodes and interfaces of GM to address one of the problems of control of technical condition of the mechanism in order to justify the proactive maintenance and R.

scholarly journals IMPROVING THE OPERATIONAL RELIABILITY OF HYDRAULIC FACILITIES WHEN USING POLYMER AND POLYMER-CEMENT COMPOSITES

2019 ◽  
pp. 217-230
Author(s):  
O. V. Kovalenko
Keyword(s):  
Composite Materials ◽  
Environmental Factors ◽  
Concrete Structures ◽  
High Strength ◽  
Cement Composite ◽  
Operational Reliability ◽  
Operating Conditions ◽  
Hydraulic Structures ◽  
Water Reclamation ◽  
Technical Solutions

Actualuty of the problem. The effective functioning of water-reclamation systems depends to a large extent on the operational reliability and durability of hydraulic structures. The structural elements of hydraulic structures of water management and reclamation complex from the moment of commissioning are subject to aggressive environmental influences. Aggressive factors (hydrostatic water pressure, alternating freezing and thawing, wetting and drying, corrosive action of salts dissolved in water, dynamic action of ice, etc.) constantly affect concrete structures, gradually destroying them. Therefore, the development of measures aimed at ensuring high resistance of structures to the aggressive environmental factors is relevant. Effective operation of structures with long-term aggressive environmental factors is only possible if they are protected (reinforced) with effective insulating, anticorrosive, high-strength, wear-resistant and cavitation-resistant composite materials. Specific characteristics of polymer and polymer-cement composite materials (high strength, corrosion resistance, frost resistance, adhesion to different coatings) enable to create effective technologies for restoring the functional capacity of hydraulic structures and increasing their stability. The need of reinforcing concrete structures of hydraulic facilities by combining or partially replacing them with modern composite materials and structures made of polymers and polymer cement is determined in view of increasing coolness, reliability and durability of the structures. These materials should be standardized at the stage of design, construction, repair and reconstruction of structures that will ensure their operational reliability and durability in aggressive environment. The development and implementation of technical solutions increasing the operational reliability and durability of hydraulic facilities for water-reclamation purposes while reducing their material and metal intensity are ones of the main areas of scientific research in the field of construction, repair and reconstruction of water-reclamation systems. Achieving high technical and economic performance of hydraulic facilities, taking into account the significant effect of aggressive environmental factors on them is possible using a scientifically sound combination of concrete and reinforced concrete structures with polymer and polymer cement composite materials. The highest level of reliability will be ensured by the structures providing the protection against damage, corrosion and filtration using the latest high performance composite materials. Optimization of technical solutions to increase the operational reliability and durability of hydraulic facilities is only possible provided that modern composite materials properties are comprehensively studied, their compliance with the requirements of water and reclamation construction, taking into account extreme operating conditions, is determined and new efficient technologies for future performance of the facilities are created. Along with expanding the use of polyme and polymer-cement composite materials, finding new varieties of polymer additives and obtaining reliable data on the durability of these materials in different operating conditions will be extended. Results. The Institute of Water Problems and Land Reclamation of NAAS has developed the main technological areas of polymer and polymer-cement composite materials application for increasing the operational reliability of hydraulic structures of water management and reclamation complex: polymeric film screens and geomembranes for increasing the anti-filtration properties; polymer and bitumen-polymer sealants for the arrangement and restoration of deformation joints; polymer and polymer-cement mixtures for structural repairs, restoration of bearing capacity, waterproofing protection, protection against filtration, accidental damage, corrosion, cavitation and actuation of hydraulic structures; concrete polymers, polymer concrete and polymer cement with high physical and mechanical properties for construction, repair and reconstruction of hydraulic structures.

scholarly journals Influence of Oil-Filled Transformers Overload Capacity on the Throughput Capacity of the Electrical Network

2018 ◽  
Vol 61 (4) ◽  
pp. 310-320
Author(s):  
V. A. Anishchenko ◽  
I. V. Gorokhovik
Keyword(s):  
Service Life ◽  
Power System ◽  
Electric Power ◽  
Power Supply ◽  
Electric Power System ◽  
Throughput Capacity ◽  
Electrical Network ◽  
Economic Losses ◽  
Insulation Material ◽  
Overload Capacity

During the operation of the electric power system, there is often a need to overload its individual elements (generators, power transformers, overhead and cable power lines, switching electric devices) for a period lasting from several dozens of minutes to a day. The overloads can be caused by intentional disconnection of parallel elements of the system because of scheduled preventive repairs, post-accident disconnections, as well as an unexpected increase in electricity consumption due to the impact of various factors. The overload capacity of the system elements makes it possible to increase operational reliability of power supply to consumers without additional expenditures while maintaining, in most cases, the almost normal service life of electrical equipment. Oil-filled transformers have the greatest potential overload capacity power, which makes it possible to consider them as a significant source of increasing the capacity of the transmission and distribution networks of the electric power system. Excessive over-current of power oil-filled transformers significantly reduces reliability and reduces their normal service life. This is due to the accelerated process of wear of the insulation material of the transfer windings as a result of overheating of the transformer oil, that causes structural changes and, as a consequence, to mechanical damage to the insulation of the windings; the latter can cause an electrical puncture. On the other hand, underestimation of the permissible overload of transformers might result in economic losses due to under-produced products when the functioning of the part of the transformers connected in parallel are ceased for scheduled preventive maintenance or as a result of forced emergency shutdowns. Therefore, there is a need to assess the potential of reasonable increase in the throughput capacity of the electrical network and, accordingly, the reliability of the power supply system, taking into account the requirements for the permissible loads of transformers when the electrical network and various operating modes are being designed.

scholarly journals Forecast of the development of an emergency at hydraulic structures of the Republic of Tatarstan

2021 ◽  
Vol 937 (3) ◽  
pp. 032020
Author(s):  
A I Shakirova ◽  
A V Kochergin ◽  
O R Sitnikov ◽  
L N Gorina
Keyword(s):  
Water Level ◽  
Degree Of Approximation ◽  
Economic Losses ◽  
Hydraulic Structures ◽  
Emergency Situations ◽  
Relevant Today ◽  
Structure Changes ◽  
Increased Risk ◽  
The Republic ◽  
High Degree

Abstract At present, a large number of hydraulic structures have been erected on the territory of the Republic of Tatarstan, which are classified as hydrodynamic hazardous facilities. Accidents at these facilities are sources of man-made emergencies. A number of hydraulic structures on the territory have been in operation without reconstruction for more than 70 years. The problem of ensuring the safety of hydraulic structures remains not fully understood and relevant today. Basically all hydraulic structures are located within or above settlements and are objects of increased risk. The consequences of a catastrophic flood can be aggravated by accidents at potentially dangerous facilities falling into its zone. The damage caused by such floods can amount to tens of millions of rubles. Incomplete destruction of the dam, when the safe operation of the structure is no longer possible, can lead to serious economic losses as a result of the cessation of energy production, hydraulic regulation and water collection in the reservoir. Careful monitoring is required in order to identify any possible emergencies. One of the solutions in this situation is the use of various methods for predicting emergency situations at hydraulic structures. In this regard, in the work, the authors have adapted a mathematical model based on Markov chains, which is distinguished by the efficiency of calculations and a high degree of approximation to statistical data. This model makes it possible to predict the state of hydraulic structures when the data on the water level and the volume of infiltration in the hydraulic structure changes. Based on the adapted model, the results of forecasting the water level for real hydraulic structures were obtained.

Wooden Trusses With Nodal Joints On Glued Flat Rods

2020 ◽  
pp. 9-15
Keyword(s):  
Bearing Capacity ◽  
Test Procedure ◽  
Experimental Studies ◽  
Operational Reliability ◽  
Design Solution ◽  
Short Term ◽  
High Degree ◽  
Wooden Structures ◽  
Node Type

Wooden trusses are widely used in construction and differ in a variety of structural forms. In general, their bearing capacity and stiffness are determined by the design solution of the node joints. In order to accept significant loads and reduce the overall deformation of trusses, it is necessary to develop new types of nodes that would also be characterized by low labor intensity of manufacturing and a high degree of operational reliability. Proposed by the authors nodes of wooden trusses based on steel glued flat rods are met the above requirements. The article describes the results of experimental studies of a wooden truss with nodal joints on glued flat rods under the short-term loads. The layout principles of the proposed node type are given; test procedure of experimental structures and results of experimental studies are presented: features of operation of steel connecting plates glued into wood in the nodes are revealed. It is shown that the adopted design solution of nodes refers to the joints of wooden structures of a rigid type and provides sufficient load-bearing capacity of the trusses and their increased rigidity. The nature of the destruction and the value of the destructive load confirmed the operational reliability of the proposed type of wooden trusses, including under the action of long-term loads. The analysis of the results revealed the directions of further improvement of wooden trusses nodes with steel glued flat rods.

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