Rail irregularities, in particular for urban rail- way infrastructures, are one of the main causes for the generation of noise and vibrations. In addition, repetitive loading may also lead to decay of the structural e...Rail irregularities, in particular for urban rail- way infrastructures, are one of the main causes for the generation of noise and vibrations. In addition, repetitive loading may also lead to decay of the structural elements of the rolling stock. This further causes an increase in main- tenance costs and reduction of service life. Monitoring these defects on a periodic basis enables the network rail managers to apply proactive measures to limit further damage. This paper discusses the measurement methods for rail corrugation with particular regard to the analysis tools for evaluating the thresholds of acceptability in re- lation to the tramway Italian transport system. Further- more, a method of analysis has been proposed： an application of the methodology used for treating road profiles has been also utilized for the data processing of rail profilometric data.展开更多
The feasibility of moni-toring the change of city settlementusing GPS surveying instead of level-ing is studied. A fiducial network anda monitoring network are establishedin Ningbo city. Two periods of GPSobservation ...The feasibility of moni-toring the change of city settlementusing GPS surveying instead of level-ing is studied. A fiducial network anda monitoring network are establishedin Ningbo city. Two periods of GPSobservation are completed. Somemeasures are taken during the obser-vation in order to ensure to obtain thehigh-precise height component. TheSaastamoinen model is adopted in thedata processing of the dry componentpart of the tropospheric delay. Thewet component change of the tropo-spheric delay is estimated by stochasticprocesses model. When Bernese soft-ware is used to process the data, themillimeter level precision of heightmeasuring is achieved.展开更多
文摘Rail irregularities, in particular for urban rail- way infrastructures, are one of the main causes for the generation of noise and vibrations. In addition, repetitive loading may also lead to decay of the structural elements of the rolling stock. This further causes an increase in main- tenance costs and reduction of service life. Monitoring these defects on a periodic basis enables the network rail managers to apply proactive measures to limit further damage. This paper discusses the measurement methods for rail corrugation with particular regard to the analysis tools for evaluating the thresholds of acceptability in re- lation to the tramway Italian transport system. Further- more, a method of analysis has been proposed： an application of the methodology used for treating road profiles has been also utilized for the data processing of rail profilometric data.
文摘The feasibility of moni-toring the change of city settlementusing GPS surveying instead of level-ing is studied. A fiducial network anda monitoring network are establishedin Ningbo city. Two periods of GPSobservation are completed. Somemeasures are taken during the obser-vation in order to ensure to obtain thehigh-precise height component. TheSaastamoinen model is adopted in thedata processing of the dry componentpart of the tropospheric delay. Thewet component change of the tropo-spheric delay is estimated by stochasticprocesses model. When Bernese soft-ware is used to process the data, themillimeter level precision of heightmeasuring is achieved.
