TH EY may not know her by face but hundreds of people can instantly recognize Chen Lianying＇s name, and her vivacious voice, In the African countries where Kiswahili is spoken, the 68yearold from Suzhou City in east ...TH EY may not know her by face but hundreds of people can instantly recognize Chen Lianying＇s name, and her vivacious voice, In the African countries where Kiswahili is spoken, the 68yearold from Suzhou City in east China＇s Jiangsu Province is regarded as the ＂voice＂ of the language, thanks to her nearly five decades＇ enadevor to present China to the world through the win dow of Kiswahili and also spread the language in China, ＂It stood me in good stead when I went shopping in the markets of Dares Salaam,＂ she said laughingly,展开更多
In this paper, an FEM （Finite Element Method） model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the ort...In this paper, an FEM （Finite Element Method） model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the orthotropic steel deck by plate elements. The natural frequencies and mode shapes are acquired by the eigen-parameter analysis. By input of a typical earthquake excitation to the bridge system, the dynamic responses of the bridge, including the displacement and accelerations of the main joints of the structure, and the seismic forces and stresses of the key members, are calculated by the structural analysis program, based on which the main laws of the seismic responses of the bridge are summarized, and the safety of the structure is evaluated.展开更多
Railway transitions experience differential movements due to differences in track system stiffness,track damping characteristics,foundation type,ballast settlement from fouling and/or degradation,as well as fill and s...Railway transitions experience differential movements due to differences in track system stiffness,track damping characteristics,foundation type,ballast settlement from fouling and/or degradation,as well as fill and subgrade settlement.This differential movement is especially problematic for high speed rail infrastructure as the 'bump' at the transition is accentuated at high speeds.Identification of different factors contributing towards this differential movement,as well as development of design and maintenance strategies to mitigate the problem is imperative for the safe and economical operation of both freight and passenger rail networks.This paper presents the research framework and initial instrumentation details from an ongoing research effort at the University of Illinois at Urbana-Champaign.Three bridge approaches experiencing recurrent geometry problems were instrumented using multidepth deflectometers(MDDs) and strain gages to identify different factors contributing to the development of differential movements.展开更多
文摘TH EY may not know her by face but hundreds of people can instantly recognize Chen Lianying＇s name, and her vivacious voice, In the African countries where Kiswahili is spoken, the 68yearold from Suzhou City in east China＇s Jiangsu Province is regarded as the ＂voice＂ of the language, thanks to her nearly five decades＇ enadevor to present China to the world through the win dow of Kiswahili and also spread the language in China, ＂It stood me in good stead when I went shopping in the markets of Dares Salaam,＂ she said laughingly,
基金Acknowledgments： This study is sponsored by the Natural Science Foundation of China （No. 90715008） and the Flander （Belgium）-China Bilateral Project （No. BIL07/07）.
文摘In this paper, an FEM （Finite Element Method） model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the orthotropic steel deck by plate elements. The natural frequencies and mode shapes are acquired by the eigen-parameter analysis. By input of a typical earthquake excitation to the bridge system, the dynamic responses of the bridge, including the displacement and accelerations of the main joints of the structure, and the seismic forces and stresses of the key members, are calculated by the structural analysis program, based on which the main laws of the seismic responses of the bridge are summarized, and the safety of the structure is evaluated.
文摘Railway transitions experience differential movements due to differences in track system stiffness,track damping characteristics,foundation type,ballast settlement from fouling and/or degradation,as well as fill and subgrade settlement.This differential movement is especially problematic for high speed rail infrastructure as the 'bump' at the transition is accentuated at high speeds.Identification of different factors contributing towards this differential movement,as well as development of design and maintenance strategies to mitigate the problem is imperative for the safe and economical operation of both freight and passenger rail networks.This paper presents the research framework and initial instrumentation details from an ongoing research effort at the University of Illinois at Urbana-Champaign.Three bridge approaches experiencing recurrent geometry problems were instrumented using multidepth deflectometers(MDDs) and strain gages to identify different factors contributing to the development of differential movements.
