Safety Of Hydraulic Structures Research Articles

Monitoring assessment of the low-pressure earthen dam of the Varnavinsky reservoir under conditions of an increasing risk of natural and man-made disasters

The need for increased attention to the reliability and safety of hydraulic structures in the water management complex of southern Russia is determined by the scale of the socio-economic consequences of their accidents. During the long-term operation of the low-pressure earthen dam of the Varnavinsky reservoir, various hidden defects and damages were formed. Which in the future can lead to a man-made disaster. The threat of catastrophic floods with the formation of hidden defects and damage will lead to natural disasters, namely the destruction of the dam body. The identification of these hidden defects and damages is a priority task in assessing the technical condition of the body of an earthen dam. The article considers only two methods of non-destructive testing for the detection of hidden defects and damage. Methods of electrocontact dynamic sounding and seismic exploration. They make it possible to obtain the electrical resistivity of soils when subdividing a section according to a lithological feature. As a result of data processing and interpretation, the geoelectric section of the electrical resistivity of soils was obtained. Applied hardware and methodological complex allowed to solve the tasks. The advantage of the complex is its methodological mobility. After a short experimental and methodological work and express processing, it is possible to clearly orient and combine the capabilities of the instrumentation complex and the engineering-geological situation in order to obtain the maximum quality and at the lowest cost of time and money. Studies of low-pressure earth dams should be carried out in the monitoring mode at various water levels in the reservoir. As can be seen from the results of processing, the geophysical complex of non-destructive testing makes it possible to study earth dams with the determination of soil parameters. To determine the physical and mechanical properties of soils, a greater amount of work should be carried out using reference drilling wells and identifying correlation dependencies of parameters.

ГИДРОТЕХНИК ИНШООТЛАР ХАВФИНИ ТАҲЛИЛ ҚИЛИШ

This article provides information and recommendations on the safety of hydraulic structures and the prevention of emergency situations.Constant monitoring of the technical condition of the structures and improving the necessary skills of the actors allowed us to anticipate possible emergencies. A great danger is the destruction of dams or dams of large reservoirs located within the borders of these settlements, in which there is a rapid flooding of nearby territories with great material and human losses. Therefore, preventive measures to prevent catastrophic events are of paramount importance.Keywords:hydraulic structures, hydrological safety, accident hazard analysis, flow wave, dam, boundary, drainage, head, reservoir

ГИДРОТЕХНИК ИНШООТЛАР ХАВФСИЗЛИГИНИ СТРАТЕГИК ТАРТИБГА СОЛИШНИНГ АСОСИЙ ЭЛЕМЕНТЛАРИ

As a result of the theoretical and experimental experiments carried out in this research work, research was carried out to prevent possible expected violations in hydraulic structures, as well as to prevent the occurrence of possible hazards that can lead to adverse events. The safety of hydraulic structures requires a lot of attention. In the process of analyzing the risks and factors associated with adverse events, as well as the management of hydraulic engineering facilities, it will be necessary to conduct practical work.Keywords:technogen, hydraulic engineering, construction, project, safety, object, event, risk, analysis, design, construction

Comparison of different methodologies for rainfall–runoff modeling: machine learning vs conceptual approach

Accurate short-term rainfall–runoff prediction is essential for flood mitigation and safety of hydraulic structures and infrastructures. This study investigates the capability of four machine learning methods (MLM), optimal pruning extreme learning machine (OPELM), multivariate adaptive regression spline (MARS), M5 model tree (M5Tree, and hybridized MARS and Kmeans algorithm (MARS-Kmeans), in hourly rainfall–runoff modeling (considering 1-, 6- and 12-h horizons). Their results are compared with a conceptual method, Event-Based Approach for Small and Ungauged Basins (EBA4SUB) and multi-linear regression (MLR). Hourly rainfall and runoff data gathered from Ilme River watershed, Germany, were divided into two equal parts, and MLM were validated considering each part by swapping training and testing datasets. MLM were compared with EBA4SUB using four events and with respect to three statistics, root-mean-square errors (RMSE), mean absolute error (MAE) and Nash–Sutcliffe efficiency (NSE). Comparison results revealed that the newly developed hybridized MARS-Kmeans method performed superior to the OPELM, MARS, M5Tree and MLR methods in prediction of 1-, 6- and 12-h ahead runoff. Comparison with conceptual method showed that all the machine learning models outperformed the EBA4SUB and OPELM provided slightly better performance than the other three alternatives in event-based rainfall–runoff modeling.

СОВЕРШЕНСТВОВАНИЕ ИНФОРМАЦИОННО-ДИАГНОСТИЧЕСКОЙ СИСТЕМЫ ПРОГРАММНО-АППАРАТНОГО КОМПЛЕКСА ДЛЯ ОБЕСПЕЧЕНИЯ БЕЗОПАСНОСТИ ГТС

The need to create a single unified information and diagnostic system to ensure the safe operation of hydraulic structures is caused by the requirements of the Federal Law ”On the safety of hydraulic structures“ (No. 117-FZ). At the current moment, the systems used are heterogeneous and are being developed according to the requirements of operation and expert organizations, while the uniformity of terminology and approach to assessing the state of objects is not ensured. The purpose of this work is to define approaches and to develop architecture for a unified information and diagnostic system. At the same time, it is necessary to ensure the performance of the minimum set of functions necessary for a comprehensive analysis of the state of hydraulic structures. There is given a description of the architecture and basic set of functions of the information system which make it possible to monitor the state of hydraulic structures. The systematization of the functionality of the existing information systems has been carried out, on the basis of the analysis the optimal composition of the minimum number of functions which provide control over the safe operation of hydraulic structures has been developed.

Dependence of the wetting rate of the loess base on the moisture conditions

The increasing demand for improved irrigation systems in the world requires a more comprehensive and widespread study of the reliability and safety of hydraulic structures. In this regard, increasing the reliability during the operation of hydraulic structures of irrigation systems, especially on collapsible soils, is very important because loess subsidence soils are widespread globally, a significant part of loess rocks are also found in Central Asia, including the Republic of Uzbekistan. This article discusses the study of the features of the joint work of full-scale irrigation structures with their loess subsidence bases and the intense - deformative state of subsidence foundations during their joint work with hydraulic structures on irrigation canals of the Kashkadarya region.

Safety of hydraulic structures in mining in the North

Safety of hydraulic structures in mining in the North

The software part, the fundamental and organizational structure of the software and hardware complex to ensure the safety of hydraulic and hydropower structures under the construction

Relevance. To ensure the safety of hydraulic and hydropower facilities, to organize constant monitoring of their condition, including the installation of additional control and measuring equipment is required. It is also necessary to introduce modern information and diagnostic systems that allow in real time to assess the state of both individual elements of the structure, as well as mutually influencing structures and complexes of structures. At the same time, the results presented in the article are aimed for describing the fundamental structure a new generation of information and diagnostic system building, developed within the framework of a software and hardware complex. The aims of the work. The main purpose of the proposed system is to increase the level of monitoring to ensure the safety of hydraulic structures, which have a possible impact on each other during operation and construction. The tasks of creating a unified platform for assessing the safe state of hydraulic structures during the construction and operation of hydraulic structures (hydroelectric and pumped-storage power plants) are being solved, the foundations of a unified information-diagnostic system on a modular basis are laid, which allows comparing monitoring and measuring equipment readings, statistical samples and calculated values obtained within the mathematical modeling objects. Methods. The paper presents the structure of the interaction of individual blocks included in the information-diagnostic system, the interaction of the information-diagnostic system with the user for decision-making during the operation of the hydraulic structures. Results. A modular shell has been implemented, consisting of a combined information-diagnostic system, expert and calculation modules, which allows a comprehensive approach to the issue of safety of mutually affecting hydraulic structures. Software links have been developed to assess the change in parameters that can lead to deviations/irregularities in the operation of the hydraulic structures.

Inverse Analysis of the Partitioning Deformation Modulusof High-Arch Dams Based on Quantum Genetic Algorithm

The physical and mechanical parameters of hydraulic structures in complicated operating conditions often change over time. Updating these parameters in a timely manner is important to comprehend the operating behaviors and monitor the safety of hydraulic structures. Conventional inverse analysis methods can only generate inversions on the comprehensive deformation modulus of concrete dam structures, which contradict practical conditions. Based on the researches on conventional reversion methods of the deformation modulus of the dam body, foundation, and reservoir basin, the objective fitness function is established in this paper according to engineering-measured data and finite element simulation results. The quantum genetic algorithm has high global search efficiency and population diversity. A mechanical parameter inversion of high-arch dams is built from the intelligent optimization of an established algorithm by applying the quantum genetic algorithm. The proposed algorithm is tested to be feasible and valid for practical engineering projects and therefore shows scientific and practical application values.

Hydraulic research results for cantilever spillway at Hydroelectric power station 2 of Chirchik – Bossuv waterway

To date, in the water sector, such urgent problems of our time as the observed decrease in the reliability and safety of hydraulic structures and their individual elements are highlighted. The level of effectiveness of water distribution management and the timely supply of electricity to consumers depends on the stable operation of the entire hydraulic complex. Water management construction is very material-intensive and requires constant expenditures of material and energy resources to maintain the level of stable operation. However, in the event of an emergency at hydroelectric power station facilities, it is extremely difficult to provide the necessary resources for carrying out restoration work on time. In the practice of hydraulic engineering, various designs of cantilevered spillways have been widely used. Reliability and trouble-free operation of such spillway structures with the conjugation of downstream divers by a jet largely depend on perfection. This article discusses the problems of local erosion in the downstream of hydraulic structures, sets out the results of experimental studies to determine the depth of local erosion behind a cantilever spillway in the outlet channel with recommendations on its end structure.

Diagnosis of concentrated leakage channel embedded in dam base by means of hydraulic tomography

Concentrated leakage channels formed in dam foundations have severe impacts on the safety of hydraulic structures. Appropriate and effective measures of prevention and remediation rely on detecting the potential spatial location and direction of concentrated leakages. In this paper, a recently developed hydraulic tomography (HT) technique is introduced to detect and locate the channels. An HT process is composed of several sequential pumping tests, data collection, and hydraulic parameter inversion. Numerical experiments designed under different conditions are carried out to test the feasibility and accuracy of HT for investigating dam-concentrated leakages. Simulation results show that even with a few pumping wells, observation ports and known hydraulic conductivities (K), the preset leakage channel, which is represented by high-K zones, can be identified. By increasing the number of pumping wells and observation ports involved in the HT test, the channel becomes legible, and the heterogeneity in the estimated K field approaches that of the true K field.

Задача планирования и управления водными ресурсами в интересах водопользователей АПК

The article presents the main areas of scientific research that are carried out by the Department of Land Reclamation and Water Management. The studies are dedicated to solving reclamation, environmental, technical and operational aspects of water supply and water use on irrigation and drainage systems, the safety of hydraulic structures, effective planning and management of water resources. Research is conducted on the basis of digital technologies, simulation of surface and groundwater movement and the spread of pollutants in the aquatic environment, geographic information technologies and aerospace sensing, optimization methods for finding compromise solutions.

Development of the design module of the software and hardware complex to ensure the safety of mutually influencing HPS

Relevance. As part of the implementation of the Federal Law No. 117-FZ “On the Safety of Hydraulic Structures”, it is necessary to continuously monitor the state of hydraulic structures and related facilities by equipping with control and measuring instruments. The development of modern computer complexes allows us to carry out and predict the state of objects by combining computational research and field observations. The work is aimed at organizing a comprehensive assessment of the state of the HPS and ensuring the safety of existing and projected mutually influential complexes. Aims of research. Improving the safety of the operated (under construction) complex of interfering hydraulic structures. Assessment of sufficient and highquality engineering and repair work carried out on the HPS. Development of recommendations for improving the efficiency of construction of new and modernization of operated hydropower facilities. HPS on the example of the Zagorsk HPS. Methods. Representation of the interaction ideology of various software systems of mathematical modeling, using control and measuring instruments data for calibration and verification of mathematical models. Results. The structure of the HSC calculation module was updated, systematization of the calculation models was carried out, interaction and transfer of the initial data to the calculation module of the software and hardware complex was revealed. The implementation of scientific research is aimed at improving the safety of the complex hydraulic structures.

Correlation between Compressive Strengths and Water Absorption of Fly Ash Cement Mortar Immersed in Water

AbstractThe compressive strength and water absorption of cement mortars with different water-binder ratio (0.35, 0.45 and 0.55) and fly ash content (0, 10%, 20% and 30%) under water immersion were investigated, and the correlation between them was further analyzed. The internal microstructure and phase composition of mortar was studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The results show that the inside of mortar mixed with fly ash displayed the loose and porous microstructure. Therefore, the incorporation of fly ash reduced the compressive strength of mortar, especially the early strength, and the strength decreased with the increase of fly ash content, and the water absorption of mortar also increased. There was a linear correlation between the compressive strength and water absorption of mortar with the equation: fc = −3.838β + 62.332, where fc and β represented the compressive strength and water absorption, respectively. Therefore, when the water absorption of mortar immersed in water was measured, its corresponding compressive strength could be preliminarily inferred through this equation, which was of great significance for detecting and identifying the stability and safety of hydraulic structures.

Analysis of the Data of Monitoring the Safety of Hydraulic Structures in the Cryolithozone

Data of long-term monitoring of the accident rate and safety of hydraulic structures in the cryolithozone from 1776 to 2015 are analyzed. A refined classification of failures and safety criteria of dams on frozen ground is given and recommendations are proposed for improving the existing building codes with respect to designing earth dams in the cryolithozone with provision of their safety during operation.

НАДІЙНІСТЬ ТА БЕЗПЕКА ГІДРОТЕХНІЧНИХ СПОРУД В УМОВАХ ТРИВАЛОЇ ЕКСПЛУАТАЦІЇ

У статті розглянуто питання забезпечення надійності та безпеки гідротехнічних споруд, що знаходяться в тривалій експлуатації. Наведено загальну характеристику гідроенергетичних об'єктів України, у тому числі Дніпровського каскаду ГЕС. Показано, що важливою проблемою гідроенергетики України слід вважати розробку спеціальних заходів щодо забезпечення безпеки гідротехнічних споруд Дніпровського каскаду ГЕС, що знаходяться в тривалій експлуатації. Дано аналіз діючих в Україні нормативних документів, що регламентують вимоги та забезпечують безпеку гідротехнічних споруд. Показано, що в даний час в Україні діє низка застарілих нормативних документів щодо надійності і безпеки гідротехнічних споруд при їх проектуванні, будівництві та експлуатації. Тому необхідно невідкладно організувати роботу зі створення сучасної нормативної бази щодо проектування, будівництва та експлуатації гідротехнічних споруд. Для правового регулювання діяльності із забезпечення безпеки гідротехнічних споруд необхідно якнайшвидше завершити розробку проекту та прийняття Закону України «Про безпеку гідротехнічних споруд». Наведено підходищодо забезпечення безпеки гідротехнічних споруд, тривалість експлуатації яких не перевищує проектного терміну служби. Критерії безпеки і технічні стани, що застосовуються в даний час до гідротехнічних споруд, що експлуатуються, є застарілими. Тому, на основі проведення спеціальних досліджень, необхідно розробити новий сучасний нормативний акт, що регламентує підходи до визначення критеріїв безпеки та відповідних цим критеріям технічних станів гідротехнічних споруд, що експлуатуються. Дано обґрунтування підходів, що дозволяють забезпечити безпеку гідротехнічних споруд, що експлуатуються, після закінчення призначеного терміну служби.

To the issue of civil liability insurance of navigable hydraulic structures

The conditions of insurance of civil liability for causing damage as a result of an accident of a hydraulic structure, stipulated by the legislation of the Russian Federation on compulsory insurance of civil liability of the owner of a hazardous object, do not fully comply with the requirements of the legislation of the Russian Federation on the safety of hydraulic structures. For example, the size of insurance sums is established regardless of the amount of financial security of civil liability, which the owner of a hydraulic structure or operating organization must have (the construction is in state ownership). Some insurance companies are taking steps to develop their own rules for assessing the risk of accidents and the size of the harm caused. It does not take into account the fact that such industry-specific methods for determining the amount of probable harm to hydraulic structures for various purposes exist and are used for a long time. This article discusses the implementation of the compulsory insurance procedure in relation to navigable hydraulic structures, which refer to the objects of state ownership. The results of the author’s comparative analysis of certain provisions of the legislation of the Russian Federation on the safety of hydraulic structures and compulsory insurance of civil liability of the owner of a hazardous object, as well as the data of operating organizations indicate the presence of a number of inconsistencies and the need for their settlement.

Some provisions of calculations of hydraulic structures according to Russian norms and American standards

Ensuring the safety of hydraulic structures should be carried out, including calculations of the stress-strain state of the system “structure–base” by the method of limit States. A summary system of reliability coefficients, a combination of loads and operating conditions for different design cases is presented. Considered the stability condition of the concrete dam on the shift on the substrate. A comparison of the values of the generalized dam stability coefficients (reserve) according to Russian norms and American standards is performed. It is shown that when comparing the numerical values of the strength and stability coefficients regulated in the Russian norms and American standards, it is necessary to take into account the methods of determining the strength characteristics of materials, the practice of taking into account loads and effects, as well as the methods of computational studies of the stress-strain state of structures and their bases.

Preliminary estimate of floods discharge in Brazil using Creager envelope curves

ABSTRACT Hydrologic studies are essential for the design and safety of hydraulic structures. In the past, a number of empirical equations were developed to represent relationships between drainage areas and observed peak discharges. Although these empirical equations have not been used frequently to study peak discharges due to the use of more detailed and sophisticated analysis, they can be used to estimate reference values, especially in ungaged sites. The objective of this paper is to assess peak discharges observed in many regions in Brazil, estimate the 10,000-year discharges according the Guia para Cálculo de Cheia de Projeto de Vertedores from Eletrobrás and compare them to the Creager envelope curves. In this study we used the records of naturalized discharges for the period of 1931 to 2012, for 131 hydroelectric projects selected in the main river basins in Brazil, using the official data published by the Operador Nacional do Sistema Elétrico (ONS) for the Sistema Interligado Nacional (SIN). The results presented in this paper show that it is possible to use the Creager envelope curves as a preliminary estimate of the design floods in Brazil. Generally, values of the Greager C coefficient between 60 and 100 are recommended for a preliminary estimate of a range of maximum discharges within drainage areas bigger than 10,000 km2. The results can be used in the preliminary estimate of maximum discharges and 10,000-year discharges for sites with no data using C values obtained from areas with enough data in the same river basin and with similar physical characteristics.

Influence of microcrack self-healing behavior on the permeability of Engineered Cementitious Composites

Engineered Cementitious Composite (ECC) is a family of high performance fiber reinforced cementitious composites featuring strain-hardening behavior and high tensile ductility (with tensile strain capacity of 3–5%). ECC achieves high ductility by forming multiple microcracks with crack width less than 60 μm under tension. The tight crack width of ECC naturally lends itself to low permeability even in the cracked stage. Such properties are of particular interest to hydraulic structure applications. In addition to the tight crack width, self-healing of microcracks further lowers the permeability of cracked ECC, enhancing the durability and safety of hydraulic structures. In this paper, the permeability of ECC composites under the influence of self-healing was experimentally studied. Single crack permeability tests were also conducted to directly correlate the permeability and self-healing behavior of a single crack with a given initial crack width. Additionally, an analytical model capable of predicting the permeability of ECC composites that undergo self-healing process is proposed and verified with experimental data. The research findings in the present paper can be used to accurately estimate the permeability of ECC and are expected to provide support for future design and application of ECC for hydraulic structures.