Research On Risk Dynamic Evaluation And Integrated Treatment Technology Of Floor Heavy In Railway Tunnel

With the increasing number of railway projects,there are more and more problems in the tunnel which is an important structure of the line, this article start with survey the reason of floor heave and corrective measures, based on the research and theoretical analysis of tunnel floor heavy for railway in China, with the result Simulation software numerical simulation,the formula for the quantity of the floor heavy is approved on the basis of summary, which is for form of floor heavy,formation mechanism and influencing factors,then the railway tunnel base structure floor heavy risk quantitative assessment system will be established.Finally, based on actual situation of railway tunnel floor heave disease expounds a variety of railway tunnel floor heave disease treatment technology. The article main research content and results are as follows:(1) Based on the site investigation and theoretical analysis, the cause of the floor heavy phenomena were obtained, and the three forms of the floor heavy were summarized: linear,pleated, arc-shaped, and the influence factors of floor heavy deformation were expounded from the aspects of rock mass, crustal stress , and engineering factors.(2) The floor heavy deformation is simulated through the FLAC3D software for different ground stress condition, different surrounding rock dilatability, different degradation degree of surrounding rock and different tunnel base structure state,analyzed the influence of different factors on the deformation of tunnel floor heave , meanwhile, the formulas for calculating the deformation of floor heave of soft rock mass under the different condition the will be raised.(3)The details of the geological radar, ultrasonic rebound method, borehole elastic modulus method and mobile rail loading car, which has been widely applied at present, will be introduced in this article, meanwhile, the deformation mechanism of floor heave of the thorough analysis and numerical simulation is put forward on the basis of a set of practical tunnel basal evaluating methods,and expounds the method of evaluation index and evaluation process.(4) The article introduces about four types of improvement methods with selectivity including "light well point precipitation"+ "grouting" and "dense dark tube precipitation"+"grouting", which are compound reinforcement technology , three-root pile and the disease area of the monolithic track-bed ,these technologies supported by floor heave phenomenon research and combined with practical engineering, and provide the theoretical foundation and engineering experience for floor heave control in the future.