A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices.The double-rod oscillation cylinder drives the tamping arm to realize vibrati...A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices.The double-rod oscillation cylinder drives the tamping arm to realize vibration.A new spin valve was designed in order to fulfill dynamic state requirements of the oscillation cylinder.Parametric analysis was carried out by establishing mathematic model.Then,the relationships among the structure of valve port and the frequency,amplitude,output shock force of the cylinder were researched.An experimental device of the electrohydraulic exciter was established to validate the theoretical results.The signals were acquired by AVANT dynamic signal analyser of vibration.The results show that new tamping device can satisfy all kinds of complex working conditions with the flexible adjustment of frequency and amplitude.展开更多
Heavy tamping is one of the important methods for ground treatment. But the vibration is often a problem that restricts the application during heavy tamping. On the other hand, as an instant impact load with controlla...Heavy tamping is one of the important methods for ground treatment. But the vibration is often a problem that restricts the application during heavy tamping. On the other hand, as an instant impact load with controllable energy, heavy tamping is a good test in situ for the study of soil dynamics. With the analysis in the field of frequency, deductive method for medium effecting function and excitation function of heavy tamping is put forward in this paper.展开更多
In the novel approach to the diagnostic tests of continuous welded rail （CWR） track by the use of the tamping machine, the fundamental statement related to the recording of the curvature with a definite value of the...In the novel approach to the diagnostic tests of continuous welded rail （CWR） track by the use of the tamping machine, the fundamental statement related to the recording of the curvature with a definite value of the lateral displacement being subjected to verification, can provide a basis for the determination of the longitudinal axial force in the rail. An attempt has also been made to define an alternative factor which by means of the measured signals, could be used for the determination of the axial forces in the rail sections. A power engineering approach has been adopted to this concept. Within the framework of the experimental investigations, measurements were carried out in the track test section. The investigations were based on stretching the rail sections by stretchers and on lateral displacements of the track by the tamping machine. The operation of the measuring apparatus was also tested in the experimental railway track section while carrying out the geometrical adjustments by the tamping machine. As a result of next series of the investigation carried out in 2006-2007, the authors worked out a procedure of estimating the longitudinal forces in rails of CWR track.展开更多
基金Projects(50975252,51275499)supported by the National Natural Science Foundation of ChinaProject(2013CB035404)supported by the National Basic Research Program of ChinaProject(GZKF-201312)supported by Open Foundation of the State Key Laboratory of Fluid Power Transmission and Control,China
文摘A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices.The double-rod oscillation cylinder drives the tamping arm to realize vibration.A new spin valve was designed in order to fulfill dynamic state requirements of the oscillation cylinder.Parametric analysis was carried out by establishing mathematic model.Then,the relationships among the structure of valve port and the frequency,amplitude,output shock force of the cylinder were researched.An experimental device of the electrohydraulic exciter was established to validate the theoretical results.The signals were acquired by AVANT dynamic signal analyser of vibration.The results show that new tamping device can satisfy all kinds of complex working conditions with the flexible adjustment of frequency and amplitude.
文摘Heavy tamping is one of the important methods for ground treatment. But the vibration is often a problem that restricts the application during heavy tamping. On the other hand, as an instant impact load with controllable energy, heavy tamping is a good test in situ for the study of soil dynamics. With the analysis in the field of frequency, deductive method for medium effecting function and excitation function of heavy tamping is put forward in this paper.
文摘In the novel approach to the diagnostic tests of continuous welded rail （CWR） track by the use of the tamping machine, the fundamental statement related to the recording of the curvature with a definite value of the lateral displacement being subjected to verification, can provide a basis for the determination of the longitudinal axial force in the rail. An attempt has also been made to define an alternative factor which by means of the measured signals, could be used for the determination of the axial forces in the rail sections. A power engineering approach has been adopted to this concept. Within the framework of the experimental investigations, measurements were carried out in the track test section. The investigations were based on stretching the rail sections by stretchers and on lateral displacements of the track by the tamping machine. The operation of the measuring apparatus was also tested in the experimental railway track section while carrying out the geometrical adjustments by the tamping machine. As a result of next series of the investigation carried out in 2006-2007, the authors worked out a procedure of estimating the longitudinal forces in rails of CWR track.
