Study On The Method For Levee Safety Assessment

It is important and meaningful to research methods of assessing the safety of levee works for which is related with the national economy and the people's livelihood. The river-way levee is regarded as main researching object in this thesis. The theory and method, such as analytic hierarchy process, grey system and so on, together with the knowledge of embankment engineering, are introduced into the thesis, which performs relatively detailed study on method of comprehensive safety assessment, synthesis assessment structure system, method of measuring assessment index and the precautionary mode of safety evaluation of the levee engineering. The main contents are as follows.1. Six rules of studying out the assessment index and the method of founding the comprehensive safety assessment structure system of the levee engineering are discussed. Also, the design of safety evaluation aggregation of the system is lucubrated and the fourth-class divisional method of safety grade is ascertained.2. The methods of standardizing original data for quantitative and qualitative safety assessment index are studied. By using these methods, the comparing difficulties between different assessment indexes at the same layer brought by the difference in expressive method, the scale of value, measuring method and units of assessment indexes of the comprehensive safety assessment structure system of the levee engineering is solved.3. Based on analyzing and comparing the existing methods of determining weight, multiplication scale method, extension AHP method and ANN method are used to the safety assessment of the levee engineering. And the model of calculating syncretic weight of safety assessment index is founded by using optimization guideline.4. According the characteristic of comprehensive safety assessment of the levee engineering, model of comprehensive safety assessment of the levee engineering is founded by using fuzzy comprehensive appraisal method and ANN theory. With the modern computer technique of software and hardware, the system of safety assessment on the levee engineering is developed.5. Based on the multi-level recursive analysis and the grey system theory, the forecast models on the safety assessment of the levee engineering are founded. And with the modern computer technique of software and hardware, the precautionary mode of the safety assessment of the levee engineering is designed.