Study On The Risk Evaluation And Treatment Decision-Making Methods Of Landslide Hazard

Landslide hazard is a serious natural hazard next only to earthquake and floodwater. It has brought about great losses to the economic and societal development worldwide. Each year it causes a loss up to billions of dollars in the whole world. A striking amount of money has been spent on the prevention and redress of the landslide hazard and much more losses have been incurred indirectly therefore. In China, 70% of the area is covered by mountains where landslide hazard happens frequently and densely. China is among those countries stricken most by this hazard. This hazard gives rise to loss with a total value of hundreds of millions yuan and great damages to the country and people's lives and properties. In order to measure the influence of hazard on life and property, a risk evaluation theory needs to be applied to. And a decision theory is necessary to design an economical and effective treatment scheme. At present, only few scholars have studied on the landslide hazard risk evaluation and treatment decision theory. The relevant theory is far from perfect. In this article, the author makes research on risk evaluation and optimal decision-making of treatment schemes of landslide hazard to reduce loss and expenditure in dealing with this hazard. The research result is of both theoretical and practical significance.Based on system engineering theory, principles of economics, risk evaluation theory, reliability theory, and decision-making theory, this article studies the risk evaluation and treatment decision-making of landslide hazard. The main research findings are as follows:(1) Based on study of the relevant literature at home and abroad, the author analyzes the research development, results, problems, and trends in this field and set his own research direction and scope accordingly.(2) From the viewpoint of systems engineering theory, the concept of large complex system of landslide hazards is put forward, on which is based to investigate the characteristics and fundamental contents about the risk analysis for landslide hazards. The hazard analysis of landslides and the vulnerability analysis of landslide hazards affected body as well as the loss evaluation of landslide hazards taken as the key contents are systematically described.(3) On the basis of reliability theory, a Bishop-based computational method for appraisal of hazard potentiality is adopted. The author analyzes the vulnerability composition, evaluation index and method, type and value of hazards-affected body, way and scale of damage on the body and ratio of value loss. After systematic study of composition of hazard damage and direct loss evaluation method, an input-output method of the indirect loss evaluation is generally proposed. Based on conclusion of available literature, an acceptable risk level is analyzed and acceptable unstable risk standard in one single hazard is set down. An average yearly casualty number in some countries and areas and yearly probability of casualty are gathered, which serve as good references for confirmation of the hazard risk level. One analysis method for expenditure efficiency of a treatment scheme is also put forward.(4) Since till now the damage and loss evaluation of secondary disaster has not been touched upon, the author proposes an evaluation model by making use of causaldiagram combining the FTA and ETA method to make reliability analysis of the secondary disaster system and forecasting of the losses thus arising from.(5) The system analysis method is adopted and an index system of comprehensive evaluation of the damage is established. Then a multi-level comprehensive evaluation model based on fuzzy mathematics theory is set up. What's more, the application of this model is further expounded with example.(6) The treatment engineering of landslide hazard is a complex systems engineering. The selection of its treatment schemes depends on such factors as technology, economics, environment, and risk. After systematic analysis an evaluation in...