Study On The Identification System For Geological Hazard Of Highway Subgrade

With high-speed development of road construction and it's increasingly significant effect for economy, the safety and patency of road were very important. However, due to various reasons, highway facilities were often threatened by geological hazard of subgrade, which caused highway traffic and social economy influence. In order to decrease loss in geological hazard of subgrade, farther measures must be taken in road design, construction and maintain management to keep a lower level of the risk. The thesis has studied the techniques and methods of geological hazard of subgrade, Based on the analyses of types of hazard, influence factors and the mechanism of the development, the thesis put forward the principles, methods of identification and index, and then the methods and function of geological hazard identification system has been constructed which choosed identification indexes, for subgrade of geological disaster prevention management, and providing technical references.On the basis of extensive literature collection, this paper summarises the main types and features of geological disasters in roadbed, and then analyses external influencing factors such as topography and geomorphology, stratigraphic lithology, geological structure, hydrogeology and so on according to collapse, landslides, roadbed subsidence. On this basis, the paper put forward common principles and methods of subgrade geological hazard identification.Based on disaster chain theory, the paper discussed the regularity of disaster chain mechanism, divided subgrade geological hazard into three stages, that early embryonic stage, metaphase imply the stage and outbreaks of late stage, then, analysised characteristics of each stage. Through the research on the subgrade engineering geological structure theory, the paper researched the relationship between the subgrade external morphology, internal structural plane and engineering properties of rock and soil mass and the subgrade geological disasters. The paper put forward new ideas that the study of subgrade geological disasters were leaded by internal subgrade engineering geological structure, natural environment was external factors and they present periodic chain reaction in combination.Finally, this paper studied screening, classification and quantification of parameter from the development stages of disaster chain based on the above and put forward overall thinking, structure, work principle and main function for subgrade geological hazard identification system. Then the paper discussed how to found the identification system of database then, researched the method of identification on three steps that hazard conditions and types, disaster stages and risk in detail.The dissertation expressed new ideas and methods of identification in subgrade geological hazard, put forward the basic function of disaster identification system frame. The author expects that it can be a help in highway disaster management and protection on early stage.