欧洲高铁对地表振动波引起的“轨道音爆”的研究

奥地利（奥匈帝国）物理学家斯扎博是世界上第一个精确描述出音爆的科学家。他对 音爆的解释是如果一个物体运动的速度和其自身发出的声波传播一样快时声波在其前方就会堆积然后产生巨大振动，既是音爆。
列车在行驶时会震动轨道地面，发出轻微的地震波，这种地震波中的瑞利波等表面波部分会沿着轨道下的地基土层向前后方的地表传播，传播速度和工程质量土质等等有关，一般是时速二、三百公里。如果列车的速度和这个自身发出的地震波一样快时，地震波就会在其前方堆积然后发生爆炸性剧烈振动，原理和音爆一样。
首先对欧洲TGV和EuroStar高铁轨道系统因列车引发的地表波类似音爆做出研究的是几个英国科学家，这里是他们的这篇著名的论文：

http://pif.sagepub.com/content/214/2/107.full.pdf+html

Rail movement and ground waves caused by high-speed trains approaching track-soil critical velocities
。。。
"Unfortunately the increased speeds of modern trains are normally accompanied with increased transient movements of the rail and ground which may cause noticeable vibrations and structure born noise in nearby buildings. For modern high-speed trains those transient movements are especially high when train speeds approach certain critical wave velocities in the track-ground system. There are two main critical wave velocities in the track-ground system: The velocity of the Rayleigh surface wave in the ground and the minimum phase velocity of bending waves propagating in the track supported by ballast, the latter velocity being referred t as the track critical velocity. Both these velocities can easily be exceeded by modern high speed trains, especially in the case of very soft soil where both critical velocities become very low.

As has been theoretically predicted by one of the authors (6,7) if a train speed V exceeds a the Rayleigh wave velocity Cr in supporting soil, then a ground vibration boom occurs which is associated with a very large increase in generated ground vibrations, as compared with the case of conventional trains. This phenomenon is similar to a sonic boom for aircraft crossing the sound barrier and its existence has recently be confirmed experimentally (8). The measurements have been carried out on behalf of the Swedish Railway Authorities when there West coast main line from Gothenburg to Malmo was opened for the X2000 high speed train. The speed achievable by the X2000 train (up to 200 km/hour can be larger than Rayleigh wave velocities in this part of south western Sweden, which is characterized by very soft ground (see also reference (9)). In particular, at a location near Ledsgard, the Rayleigh wave velocity in the ground was as low as 45 m/s, so that the increase in train speed from 140 to 180km/hr, lead to an increase by a factor of about 10 in the generated ground vibration level (8). The above mentioned first observations of a ground vibration boom indicate that it is now possible to speak about "supersonic" or (more precisely) "trans-Rayleigh" trains (10-12). The increased attention of local authorities and railway companies to ground vibrations associated with high speed trains has stimulated a growing number of theoretical and experimental investigations in this area (see, e.g., references (13) to (16)).

If train speeds increase further and approach the track critical velocity, then rail deflections due to applied axle loads become especially large. Possible very large rail deflections at this speed may even result in train derailment, thus representing a serious problem of train and passenger safety (9.17-19).


列车”音爆“后的那段轨道路基会松动移位，会严重影响后继列车的安全和危及旅客的生命，对附近的建筑结构也会造成损害。近年来世界各国为了和廉价民航竞争铁路的速度越来越快，这个问题也开始越来越突出。这里是欧洲高铁人提出的在轨道设计针对轨道音爆问题的一些建议：

http://gow.epsrc.ac.uk/NGBOViewGrant.aspx?GrantRef=EP/H027262/1

Development of Design Guidelines for High-speed Railway Track Including Critical Track Velocities and Track Mitigation Strategies








奥地利（奥匈帝国）物理学家斯扎博是世界上第一个精确描述出音爆的科学家。他对 音爆的解释是如果一个物体运动的速度和其自身发出的声波传播一样快时声波在其前方就会堆积然后产生巨大振动，既是音爆。
列车在行驶时会震动轨道地面，发出轻微的地震波，这种地震波中的瑞利波等表面波部分会沿着轨道下的地基土层向前后方的地表传播，传播速度和工程质量土质等等有关，一般是时速二、三百公里。如果列车的速度和这个自身发出的地震波一样快时，地震波就会在其前方堆积然后发生爆炸性剧烈振动，原理和音爆一样。
首先对欧洲TGV和EuroStar高铁轨道系统因列车引发的地表波类似音爆做出研究的是几个英国科学家，这里是他们的这篇著名的论文：

http://pif.sagepub.com/content/214/2/107.full.pdf+html

Rail movement and ground waves caused by high-speed trains approaching track-soil critical velocities
。。。
"Unfortunately the increased speeds of modern trains are normally accompanied with increased transient movements of the rail and ground which may cause noticeable vibrations and structure born noise in nearby buildings. For modern high-speed trains those transient movements are especially high when train speeds approach certain critical wave velocities in the track-ground system. There are two main critical wave velocities in the track-ground system: The velocity of the Rayleigh surface wave in the ground and the minimum phase velocity of bending waves propagating in the track supported by ballast, the latter velocity being referred t as the track critical velocity. Both these velocities can easily be exceeded by modern high speed trains, especially in the case of very soft soil where both critical velocities become very low.

As has been theoretically predicted by one of the authors (6,7) if a train speed V exceeds a the Rayleigh wave velocity Cr in supporting soil, then a ground vibration boom occurs which is associated with a very large increase in generated ground vibrations, as compared with the case of conventional trains. This phenomenon is similar to a sonic boom for aircraft crossing the sound barrier and its existence has recently be confirmed experimentally (8). The measurements have been carried out on behalf of the Swedish Railway Authorities when there West coast main line from Gothenburg to Malmo was opened for the X2000 high speed train. The speed achievable by the X2000 train (up to 200 km/hour can be larger than Rayleigh wave velocities in this part of south western Sweden, which is characterized by very soft ground (see also reference (9)). In particular, at a location near Ledsgard, the Rayleigh wave velocity in the ground was as low as 45 m/s, so that the increase in train speed from 140 to 180km/hr, lead to an increase by a factor of about 10 in the generated ground vibration level (8). The above mentioned first observations of a ground vibration boom indicate that it is now possible to speak about "supersonic" or (more precisely) "trans-Rayleigh" trains (10-12). The increased attention of local authorities and railway companies to ground vibrations associated with high speed trains has stimulated a growing number of theoretical and experimental investigations in this area (see, e.g., references (13) to (16)).

If train speeds increase further and approach the track critical velocity, then rail deflections due to applied axle loads become especially large. Possible very large rail deflections at this speed may even result in train derailment, thus representing a serious problem of train and passenger safety (9.17-19).


列车”音爆“后的那段轨道路基会松动移位，会严重影响后继列车的安全和危及旅客的生命，对附近的建筑结构也会造成损害。近年来世界各国为了和廉价民航竞争铁路的速度越来越快，这个问题也开始越来越突出。这里是欧洲高铁人提出的在轨道设计针对轨道音爆问题的一些建议：

http://gow.epsrc.ac.uk/NGBOViewGrant.aspx?GrantRef=EP/H027262/1

Development of Design Guidelines for High-speed Railway Track Including Critical Track Velocities and Track Mitigation Strategies