长沙中低速磁浮低置结构提速动力响应试验研究

Experimental Study on Speed-up Dynamic Response of Changsha Medium and Low Speed Maglev Line

随着我国交通的发展及城市客运量的不断增加,提速成为中低速磁浮发展和推广的核心竞争力。为研究长沙中低速磁浮低置结构段最高运营速度,在长沙磁浮低置结构段开展动力响应现场试验,实测不同时速、载荷等工况下低置结构振动加速度、动位移与动应变以及车辆振动等,分析承轨梁、路基、车辆的动力响应特征,得出长沙磁浮低置结构动力响应变化规律与建议运营速度。结果表明:当试验速度为100~125 km/h时,承轨梁、路基及车辆的各动力指标均满足规范要求;当试验速度达到130 km/h时,超载工况下车辆垂向加速度最大为1.14 m/s^(2),超过规范限值且列车运行过程中存在磁浮掉点砸轨现象;建议长沙磁浮低置结构段最高运营速度不高于125 km/h;行车平顺性和舒适性是影响磁浮提速的主要因素。长沙磁浮正式提速运营至今已达半年,运行平稳,相关研究成果可供磁浮提速工程参考。

With the development of China􀆳s transportation and the continuous increase of urban passenger traffic,speed-up has become the core competitiveness of the development and promotion of medium and low speed maglev.In order to study the maximum operating speed of the low at-ground structure of Changsha medium and low-speed maglev,the dynamic response field test is carried out,and the low at-ground structure􀆳s dynamic acceleration,dynamic displacement,dynamic strain and vehicle vibration are measured under different speed and load conditions.Further,the dynamic response characteristics of beam supporting track,subgrade and vehicle body are analyzed,and the changing rule of the dynamic response and the recommended operating speed of the Changsha maglev􀆳s low at-ground structure are obtained.Relevant results indicate that when the speed is 100~125 km/h,all the dynamic indexes of the beam supporting track,subgrade and vehicle meet the specification requirements;when the test speed reaches 130 km/h,the maximum vertical acceleration of the vehicle under the overload conditions is 1.14 m/s^(2),which exceeds the specification limit;and magnetic levitation point-dropping and rail-hitting occur during operation.It is recommended that the maximum operating speed of the Changsha maglev low at-ground structural section should not exceed 125 km/h.Smooth running and riding comfort are the main factors affecting the maglev􀆳s speed-up.Changsha maglev has been in stable operation for about half a year.Relevant results can provide some reference for the maglev􀆳s speed-up transformation.