Results of in-situ vibration measurement carried out at Tianjin West Elevated Railway Station which has the trains running on the station structure were reported. The main excitation source is the train passing throug...Results of in-situ vibration measurement carried out at Tianjin West Elevated Railway Station which has the trains running on the station structure were reported. The main excitation source is the train passing through the station. Vibration measurements were recorded in the vertical direction of the supporting track beam, the platform and the steel truss beam of the waiting hall, as well as in the vertical, longitudinal and transverse directions of the roof arch base of the station. Acceleration time responses were obtained. The maximum value, vibration level and one-third octave band RMS spectra of the measured accelerations were studied. The propagation of vibration in different structural floors was discussed. The influence of train speed, distance to the vibration source and the type of train on the structural vibration were analyzed. Results show that the vibration level increases with the train speed, while it attenuates with the distance to the track. Furthermore, the vibration responses of different structural floors were compared, and it is noted that the vertical vibration of the bottom slab of the platform is most severe and the transverse vibration of the roof arch base is the smallest. The results provide reference on the vibration characteristics and vibration energy distribution of this type of "Train on building frame" system used as an elevated railway station.展开更多
Different cities have different climate conditions and outdoor temperature and humidity, so the scheme of an environment control in subway should be analyzed by considering objective conditions, project cost and opera...Different cities have different climate conditions and outdoor temperature and humidity, so the scheme of an environment control in subway should be analyzed by considering objective conditions, project cost and operating status. In this paper, a physical and mathematical model is built according to the design of Shenyang subway (line 1), the boundary conditions of the model are defined by the design and experiments, the numerical analysis of ventilating scheme and air conditioning scheme is introduced individually, and the temperature field and air flow field of the two schemes are compared, so that the feasibility of using a ventilating scheme in subway of northeast cities is discussed. Considering comfort and economy, it can be concluded that mechanical ventilation is feasible in subway of northeast cities because the air temperature there is not very high in summer.展开更多
The study was motivated by the fact that explosion inside the subway structure may not only cause direct life loss,but also damage the subway structure and lead to further loss of lives and properties.The propagation ...The study was motivated by the fact that explosion inside the subway structure may not only cause direct life loss,but also damage the subway structure and lead to further loss of lives and properties.The propagation law of explosion wave in the subway station was analyzed and a simplified model of overpressure in the subway station was also proposed.Whereafter,the improved dynamic cam-clay model of soil and the concrete damaged plasticity constitutive model were used for the dynamic analysis of the subway station.Meanwhile,the influences of soil stiffness and burial depth on the dynamic response of the subway station were looked into.The results show that the multi-peak overpressure in the subway station does not appear,and large stresses concentrate on the central column and the floor slab of the subway station,so some special reinforcement measures should be taken in these parts.The effect of soil stiffness and burial depth on the stress of the central column is little;however,the effect on the stress of the station side wall is relatively obvious.展开更多
This paper discusses the use of Underground Metro stations and tunnels as protective structures in case of nuclear emergencies. Six lines are taken as a case study to investigate the use of their underground stations ...This paper discusses the use of Underground Metro stations and tunnels as protective structures in case of nuclear emergencies. Six lines are taken as a case study to investigate the use of their underground stations and tunnels. The research explains the structural design of Underground Metro and the necessary needs for hidden people inside Underground Metro used as shelters. The research investigates the calculations of the number of hidden persons inside Underground Metro used as shelters. A field study has been conducted to an Underground Metro station to detemaine the peaceful use and the emergency use of all basements of the station. Also, the field study aims to determine the existing spaces and the needed spaces of the Underground Metro station to dual--used as a nuclear shelter. Three Underground Metro stations have been selected and a field study has been conducted to determine the usages of these basements, the planning, general and design features for each one of them, and whether they can be used as protective structures for citizens in emergencies. These basements were compared for their protective factors. Also, their capacities for sheltering were calculated.展开更多
A station carrying capacity calculation method based on the station blocking time method is proposed.According to the station track circuit groups,signal system and station topological structure,the station blocks are...A station carrying capacity calculation method based on the station blocking time method is proposed.According to the station track circuit groups,signal system and station topological structure,the station blocks are divided and the division principle is proposed.Then the train routes model is built based on the station blocking time method.The calculation methods of the train arrival headway and departure headway at the station are redefined.The optimal capacity calculation model and algorithm based on a given train operation plan are studied by analyzing the optimal operation sequence of trains with different train speeds and operation types.With the case study of Jinan West Railway Station of Beijing-Shanghai high-speed railway in China,the minimum arrival headway between two trains with the speeds of 300 and 250 km/h can be reduced to 3.0 and 2.7 min,respectively.The maximum calculation results of the calculation methods can be increased from 13 train/h to 16 train/h.This method can increase the number of trains within a period of time in a station while meeting the transport organization and passenger service requirements.展开更多
This paper intends to study Ezra Pound＇s early poetics and his modemist poetry through a close research of the Eastern elements in the shaping process of his poetics and the significance and influence of his poetic t...This paper intends to study Ezra Pound＇s early poetics and his modemist poetry through a close research of the Eastern elements in the shaping process of his poetics and the significance and influence of his poetic thoughts on the American New Poetry Movement. In order to clarify the essence of Pound＇s early poetics under the influence of Chinese classical poems, the paper starts from the discussion of the influence of Cathay （1915） and his translation of Cathay; then it provides a detailed analysis of the relationship between Chinese classical poems and Pound＇s creation; and finally it has given an analysis of ＂In a Station of the Metro＂. Pound absorbed different poetic concepts from all of them and transformed his poetry from the conventional Romanticism to the innovative Modemism. What Pound innovated in the poetry composition is of great importance if the new era wishes to shake off the banality and out-of-date tradition in literature. Pound changed a whole generation of poets and set a good example for those who desire to write in a new way展开更多
This paper select the escalator with large flow in the station as the object, analysing the correlation of the AFC data of the in and out gates and the passenger flow parameters by passenger flow density and the passi...This paper select the escalator with large flow in the station as the object, analysing the correlation of the AFC data of the in and out gates and the passenger flow parameters by passenger flow density and the passing time acquired and calculated in the waiting area of the prediction escalator to select the gates related to the predicted the escalator. NARX neural network is used to predict the model of the passenger flow parameters of the escalator waiting area based on the related gates＇ AFC data, then a probabilistic neural network model was established by using the AFC data and predicted passenger flow parameters as input and the passenger flow status in the escalator waiting area of subway station as output.The result shows the predicting model can predict the passenger flow status of the escalator waiting area better by the AFC data in the subway station. Research result can provide decision basis for the operation management of the subway station.展开更多
Effect of different fire strengths on the smoke distribution in the subway station is investigated. Shin-Gum-Ho station （line #5） in Seoui is selected as a case study for variation of CO （carbon monoxide） distribu...Effect of different fire strengths on the smoke distribution in the subway station is investigated. Shin-Gum-Ho station （line #5） in Seoui is selected as a case study for variation of CO （carbon monoxide） distribution caused by the fire in the platform. The ventilation in the station is set to be an air supply mod in the lobby and an air exhaustion mod in the platform. One-side main tunnel ventilation （7,000 m3/min） is applied to operate in the tunnel. The fire is assumed to break out in the middle of train parked in the platform tunnel. Two kinds of fire strength are used. One is 10 MW and the other is 20 MW. Ventilation diffusers in the station are modeled as 317 square shapes ＆ four rectangular shapes in the lobby and platform. The total of 7.5 million grids is generated and whole domain is divided to 22 blocks for parallel computation. Large eddy simulation method is applied to solve the momentum equation. The behavior of CO is calculated according to different fire strengths and compared with each other.展开更多
基金Project(50938008)supported by the Natural Science Foundation of Beijing,ChinaProject(2012JBM007)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(NCET-11-0571)supported by the Program for New Century Excellent Talents in University,China
文摘Results of in-situ vibration measurement carried out at Tianjin West Elevated Railway Station which has the trains running on the station structure were reported. The main excitation source is the train passing through the station. Vibration measurements were recorded in the vertical direction of the supporting track beam, the platform and the steel truss beam of the waiting hall, as well as in the vertical, longitudinal and transverse directions of the roof arch base of the station. Acceleration time responses were obtained. The maximum value, vibration level and one-third octave band RMS spectra of the measured accelerations were studied. The propagation of vibration in different structural floors was discussed. The influence of train speed, distance to the vibration source and the type of train on the structural vibration were analyzed. Results show that the vibration level increases with the train speed, while it attenuates with the distance to the track. Furthermore, the vibration responses of different structural floors were compared, and it is noted that the vertical vibration of the bottom slab of the platform is most severe and the transverse vibration of the roof arch base is the smallest. The results provide reference on the vibration characteristics and vibration energy distribution of this type of "Train on building frame" system used as an elevated railway station.
文摘Different cities have different climate conditions and outdoor temperature and humidity, so the scheme of an environment control in subway should be analyzed by considering objective conditions, project cost and operating status. In this paper, a physical and mathematical model is built according to the design of Shenyang subway (line 1), the boundary conditions of the model are defined by the design and experiments, the numerical analysis of ventilating scheme and air conditioning scheme is introduced individually, and the temperature field and air flow field of the two schemes are compared, so that the feasibility of using a ventilating scheme in subway of northeast cities is discussed. Considering comfort and economy, it can be concluded that mechanical ventilation is feasible in subway of northeast cities because the air temperature there is not very high in summer.
基金Project(50978043) supported by the National Natural Science Foundation of China
文摘The study was motivated by the fact that explosion inside the subway structure may not only cause direct life loss,but also damage the subway structure and lead to further loss of lives and properties.The propagation law of explosion wave in the subway station was analyzed and a simplified model of overpressure in the subway station was also proposed.Whereafter,the improved dynamic cam-clay model of soil and the concrete damaged plasticity constitutive model were used for the dynamic analysis of the subway station.Meanwhile,the influences of soil stiffness and burial depth on the dynamic response of the subway station were looked into.The results show that the multi-peak overpressure in the subway station does not appear,and large stresses concentrate on the central column and the floor slab of the subway station,so some special reinforcement measures should be taken in these parts.The effect of soil stiffness and burial depth on the stress of the central column is little;however,the effect on the stress of the station side wall is relatively obvious.
文摘This paper discusses the use of Underground Metro stations and tunnels as protective structures in case of nuclear emergencies. Six lines are taken as a case study to investigate the use of their underground stations and tunnels. The research explains the structural design of Underground Metro and the necessary needs for hidden people inside Underground Metro used as shelters. The research investigates the calculations of the number of hidden persons inside Underground Metro used as shelters. A field study has been conducted to an Underground Metro station to detemaine the peaceful use and the emergency use of all basements of the station. Also, the field study aims to determine the existing spaces and the needed spaces of the Underground Metro station to dual--used as a nuclear shelter. Three Underground Metro stations have been selected and a field study has been conducted to determine the usages of these basements, the planning, general and design features for each one of them, and whether they can be used as protective structures for citizens in emergencies. These basements were compared for their protective factors. Also, their capacities for sheltering were calculated.
基金The National Natural Science Foundation of China(No.51668048)the Natural Science Foundation of Inner M ongolia(No.2017BS0501)
文摘A station carrying capacity calculation method based on the station blocking time method is proposed.According to the station track circuit groups,signal system and station topological structure,the station blocks are divided and the division principle is proposed.Then the train routes model is built based on the station blocking time method.The calculation methods of the train arrival headway and departure headway at the station are redefined.The optimal capacity calculation model and algorithm based on a given train operation plan are studied by analyzing the optimal operation sequence of trains with different train speeds and operation types.With the case study of Jinan West Railway Station of Beijing-Shanghai high-speed railway in China,the minimum arrival headway between two trains with the speeds of 300 and 250 km/h can be reduced to 3.0 and 2.7 min,respectively.The maximum calculation results of the calculation methods can be increased from 13 train/h to 16 train/h.This method can increase the number of trains within a period of time in a station while meeting the transport organization and passenger service requirements.
文摘This paper intends to study Ezra Pound＇s early poetics and his modemist poetry through a close research of the Eastern elements in the shaping process of his poetics and the significance and influence of his poetic thoughts on the American New Poetry Movement. In order to clarify the essence of Pound＇s early poetics under the influence of Chinese classical poems, the paper starts from the discussion of the influence of Cathay （1915） and his translation of Cathay; then it provides a detailed analysis of the relationship between Chinese classical poems and Pound＇s creation; and finally it has given an analysis of ＂In a Station of the Metro＂. Pound absorbed different poetic concepts from all of them and transformed his poetry from the conventional Romanticism to the innovative Modemism. What Pound innovated in the poetry composition is of great importance if the new era wishes to shake off the banality and out-of-date tradition in literature. Pound changed a whole generation of poets and set a good example for those who desire to write in a new way
文摘This paper select the escalator with large flow in the station as the object, analysing the correlation of the AFC data of the in and out gates and the passenger flow parameters by passenger flow density and the passing time acquired and calculated in the waiting area of the prediction escalator to select the gates related to the predicted the escalator. NARX neural network is used to predict the model of the passenger flow parameters of the escalator waiting area based on the related gates＇ AFC data, then a probabilistic neural network model was established by using the AFC data and predicted passenger flow parameters as input and the passenger flow status in the escalator waiting area of subway station as output.The result shows the predicting model can predict the passenger flow status of the escalator waiting area better by the AFC data in the subway station. Research result can provide decision basis for the operation management of the subway station.
文摘Effect of different fire strengths on the smoke distribution in the subway station is investigated. Shin-Gum-Ho station （line #5） in Seoui is selected as a case study for variation of CO （carbon monoxide） distribution caused by the fire in the platform. The ventilation in the station is set to be an air supply mod in the lobby and an air exhaustion mod in the platform. One-side main tunnel ventilation （7,000 m3/min） is applied to operate in the tunnel. The fire is assumed to break out in the middle of train parked in the platform tunnel. Two kinds of fire strength are used. One is 10 MW and the other is 20 MW. Ventilation diffusers in the station are modeled as 317 square shapes ＆ four rectangular shapes in the lobby and platform. The total of 7.5 million grids is generated and whole domain is divided to 22 blocks for parallel computation. Large eddy simulation method is applied to solve the momentum equation. The behavior of CO is calculated according to different fire strengths and compared with each other.
