Study On Theory And Computation Technique Of Structural System Failure Evaluation And Dam-break Flood Based On Numerical Simulation

As China’s reform and opening get up significant achievements, there are better socio-economic development, national economic and social life has been enhanced, government departments at all levels is becoming more and more attention to public emergencies warning and processing, the emergency plan has become an important basis for rescue, reducing loss of life and property, maintaining social stability and embody the social harmony are extremely important. In "the national medium-and long-term science and technology development planning framework (2006-2020) ", the" public safeties "are become as the national scientific research in the areas of focus. In order to enhance water emergencies risk awareness and prevention awareness, accelerate reservoir for flood emergency preparation work pace, the project of "Research on Dam Break Problems and Risk Zone" is supported by Hubei Water Resources Bureau in 2009, and is become as the Hubei provincial water key scientific research projects for research. This dissertation is important results of the project.In this dissertation, the main content and features are:(1) the dam-break location, scope and geometric dimensions, etc are first quantified by failure probability of cross-dam structure system. (2) The unit group method of throughout dam-body’s cells is first introduced and used, it is evaluated the dam-break may happen. (3) By dam instance inverse analysis, in the present situation with safety factor when determining the dam safety, dam-break first occurred in compression and shear safety factor is less than 1 M-C dam across the site, the final collapse of scope cover safety coefficient 2.0 M-C. (4) The RCC arch dam of dam-break issues is first used numerical simulation method. (5) In focus of RCC materials reliability, the random variables of partial coefficients and probability distribution functions are first used together, in order to reduce feature function more random variables. (6) Based on the Weir and wave flow equal, first established the instantaneous dam-break maximum discharge and Weir discharge relations: ;the flow calculation formula of the instantaneous dam-break flood peak computing, gradually dam-break flow and weirs flow are unified. (7) Their parameters are first unified Weir, it ensure that the parameters of reliability. (8) The instantaneous dam-break flood hydrograph calculation formula is first given:(9) The research results are first system brought, in order to establish and improve the flood control and the early warning system.The full dissertation is divided into nine chapters. The first chapter is introduction; to elucidation bring upping of the topic, to present research condition important meaning in domestic and international, to include research contents and innovation points. The second chapter is dam-break events for statistical analysis and dam structure failure probability analysis, experience points out:concrete dam design life although long, but the dam probability in average, arch dam is also slightly higher than average. The third chapter is Inverse analysis the XiaoZhaizi River arch dam fact-finding preliminary study on the use, now commonly used quantitative safety factor determines the break mouth parts, scope and geometrical dimensions, found:break mouth first occurred in compression and shear safety factor is less than 1 M-C dam across the site, the final collapse of covering regional safety coefficient 2.0 M-C. The 4th chapter is one of most important chapters in this dissertation. It numerical simulates three-dimensional roller-compacted-concrete (RCC) high arch dam structure system failure, first of all, a more detailed analysis of the Zhao-Lai-He RCC arch dam material parameters, withstand loads of random characters and (probabilistic parameters) standard values; in theory analysis of the factor of safety and reliability of the relationship that works with safety factor characterization:safety deficiencies; and then, from the arch dam characteristics and probability theory research structure dam risk theory, first proposed structure dam failure calculation method of the cell through the dam-body; grouping method for the first time application failure probability quantification dam-break scope; focused on the reliability of the RCC material, the first load of partial coefficients and material parameters of probability distribution functions use a combination of organic, avoid multiple random failure probability. The 5 th chapter analyzes lack for now dam-break flow calculation formula. The 6th chapter is another of most important chapters in this dissertation of dam-break flood (process) the calculation formula and the recommendation. It analyses through dam water flow, flow analysis of convergence on downstream to, identifying dam-break weir is a of three weirs forms of thin-walled Weir, line Weir and broad-crested, flow cross section is trapezoidal most natural reality; deduction of trapezoidal cross dam flow calculation formula, lists the relevant parameter, and use Matlab to flow coefficient, drowning, and lateral contraction coefficient data parameters formulaic fitting; and domestic and international dam flow comparative analysis of the reasonableness of its formula; based on the Weir and wave flow equal, first established the instantaneous dam-break maximum flow and Weir relationship: . Thus the maximum instantaneous dam flood peak computing, gradually dam flood and diffuse dam flood process calculation formula and the arguments to the Weir flow calculation up; provides instantaneous dam flood hydrograph calculation formula. The 7th chapter verifies overtop dam flow calculation formula of the Maanguan reservoir overtopping flood process instance inverse analysis. The 8th chapter simulates the Zhaolaihe hub encounter emergencies overtopping and instantaneous dam flow process. The 9th chapter gives the summary, innovation point and bring upped the outlook.To sum up, this dissertation-"Study on theory and computation technique of structural system failure evaluation and dam-break flood based on numerical simulation":Research interests focus on the subject in front of reliability theory and Weir wave flow theory of extension development, on the structure system of evaluation of pass-cross failure and dam-break flood computing theory, methods are clearly innovative and advanced nature, make creative results. Research results meet the production project of "Research on Dam Break Problems and Risk Zone", to develop the reservoir flood emergency plan, the first research results provided by the system. On social development and the national economic construction have important practical significance and far-reaching political significance; there is a huge social and economic benefit, storage with theoretical and academic high energy value.