The Study Of Vibration Of High Speed Maglev Guideway Interacting With Vehicle

Maglev guideway is the main part of high speed maglev transportation system. The design of the guideway in Shanghai Line is carried out according to the empirical formula suggested by the German company. This formula demands too high on rigidity of the guideway and causes great problems in design and construction. With the development of maglev transportation system it is demanded to increase the guideway span to cross rivers and main roads in city and it will be harder to adopt the German formula as the basis in design. In order to optimize the current guideway and develop new style of the guideway it is necessary to study the problems associated with maglev vehicle/guideway interaction and to understand the dynamical characteristics of maglev guideway.According to the structure of the German maglev vehicle, a detailed interaction model which consists of ten-degree-of-freedom vehicle model, magnet model, vertically flexible guideway model, and control system model is developed. With this model the vibration of the guideway used in Shanghai Line is studied. The theoretical results are compared with the test results and optimization advices are suggested; New style of guideways which are suit for medium span are developed. Based upon numerical simulations on current guideway and new style of guideways the relations between the vibration of the guideway and the parameters of the system are studied. The conclusions are described as follows:1. The vibration of the guideway used in Shanghai Line is studied with the model and corresponding program proposed above. The results show that vehicle speeds, guideway span, primary frequency and damping ratio of the guideway have an important influence on the response of the guideway. The German formula is proved to be conservative and the definite way is to control impact coefficient and acceleration of the guideway.2. The plans of new type of guideways, which are three-span continuous guideway and three-span rigid frame bridge, are developed. The relations between the deformation, primary frequency of the guideways and the span ratio, the rigidity of the pier have been discussed. It can be concluded that the adoption of span ratio between 0.5 and 0.7 and 2.4 for the linear rigidity ratio of pier to beam is reasonable. These plans have been examined by the committee of 863 Project and became technical reserve for subsequent maglev project.3. The vibration of medium span guideways has been studied. It is shown that the dynamic response of guideway increases with the increasing of the vehicle speed and decreases with the increasing of the guideway rigidity. It is beneficial to adopt smaller span ratio in design.4. The relation between the impact coefficient and the guideway rigidity can be used to determine the section of the guideway. It is suggested that in design it is suitable to determine the lower limit and upper limit of the rigidity first, find out the scope where the dynamic response of guideway is non-sensitive to the increase of the rigidity, and finally select the proper cross section of the guideway.5. Based on the test results of the Shanghai Line the comparison between the simulation results and the test results is carried out. It is proved that the analytical method, the models and the programs proposed above are credible and can serve the dynamical design of maglev guideway.