Taizhou Bridge is the first kilometer level three-pylon two-span suspension bridge in the world and the structural complexity has significant effects on the seismic performance of the bridge. Shaking table test of Tai...Taizhou Bridge is the first kilometer level three-pylon two-span suspension bridge in the world and the structural complexity has significant effects on the seismic performance of the bridge. Shaking table test of Taizhou Bridge is arranged to investigate the effects of non-uniform ground motion input, collision between main and side spans and optimal seismic structural system. It's very important and difficult to design and manufacture the scaled down model of Taizhou Bridge used during the shaking table test. The key point is that the girder and pylons are very hard to be manufactured if the similarity ratio is strictly followed. Based on the finite element method (FEM) analysis, a simplified scaled down model is designed and the bending stiffness of the girder and pylon are strictly simulated, and the torsion stiffness and axial stiffness are not strictly simulated. The inner forces and displacements of critical sections, points of simplified model and theoretical model are compared by FEM analysis, and it's found out that the difference between the seismic responses is relatively small. So, the simplified model can be used to conduct the shaking table test by the FEM verification.展开更多
For the first time an anti-shock packaging model of an acoustic-vibration sensor system has been designed by using the shocking isolation principle. The finite element analysis has been applied for design and simulati...For the first time an anti-shock packaging model of an acoustic-vibration sensor system has been designed by using the shocking isolation principle. The finite element analysis has been applied for design and simulation of the model. The effects of Young’s modulus of anti-shock rubber on naturally occurring frequencies of the combination of rubber and an acoustic sensor chip were analyzed. The displacement of the acoustic sensor chip is loaded with force. The results of static analysis and harmonic analysis show that while increasing Young’s modulus of anti-chock rubber, the first five natural frequencies of the package body also increases. Yet the displacement of the acoustic sensor chip around the resonant frequency decreases. The results of static and transient analysis show that the displacement of the acoustic sensor chip decreases with the increase of Young’s modulus of anti-chock rubber being loaded with either transient force or static force at the bottom of the combination of rubber and acoustic sensor chip.展开更多
Shapai Roller Compacted Concrete(RCC) Arch Dam is the highest RCC arch dam of the 20th century in the world with a maximum height of 132m,and it is the only concrete arch dam near the epicentre of Wenchuan earthquake ...Shapai Roller Compacted Concrete(RCC) Arch Dam is the highest RCC arch dam of the 20th century in the world with a maximum height of 132m,and it is the only concrete arch dam near the epicentre of Wenchuan earthquake on May 12th,2008.The seismic damage to the dam and the resistance of the dam has drawn great attention.This paper analyzed the response and resistance of the dam to the seismic wave using numerical simulations with comparison to the monitored data.The field investigation after the earthquake and analysis of insitu data record showed that there was only little variation in the opening size at the dam and foundation interface,transverse joints and inducing joints before and after the earthquake.The overall stability of the dam abutment resistance body was quite good except a little relaxation was observed.The results of the dynamic finite element method(FEM) showed that the sizes of the openings obtained from the numerical modeling are comparable with the monitored values,and the change of the opening size is in millimeter range.This study revealed that Shapai arch dam exhibited high seismic resistance and overload capacity in the Wenchuan earthquake event.The comparison of the monitored and simulated results showed that the numerical method applied in this paper well simulated the seismic response of the dam.The method could be useful in the future application on the safety evaluation of RCC dams.展开更多
基金National Science and Technology Support Program of China(No.2009BAG15B01)Key Programs for Science and Technology Development of Chinese Transportation Industry(No.2008-353-332-190)+2 种基金Natural Science Foundation of China(No.50708074)the Ministry of Science and Technology of China(No.SLDRCE08-B-04)Kwang-Hua Fund for College of Civil Engineering,Tongji University
文摘Taizhou Bridge is the first kilometer level three-pylon two-span suspension bridge in the world and the structural complexity has significant effects on the seismic performance of the bridge. Shaking table test of Taizhou Bridge is arranged to investigate the effects of non-uniform ground motion input, collision between main and side spans and optimal seismic structural system. It's very important and difficult to design and manufacture the scaled down model of Taizhou Bridge used during the shaking table test. The key point is that the girder and pylons are very hard to be manufactured if the similarity ratio is strictly followed. Based on the finite element method (FEM) analysis, a simplified scaled down model is designed and the bending stiffness of the girder and pylon are strictly simulated, and the torsion stiffness and axial stiffness are not strictly simulated. The inner forces and displacements of critical sections, points of simplified model and theoretical model are compared by FEM analysis, and it's found out that the difference between the seismic responses is relatively small. So, the simplified model can be used to conduct the shaking table test by the FEM verification.
基金Sponsored by the Creativity Ability Fund Project for Cadreman of General Provincial University of Heilongjiang(Grant No.1053G033).
文摘For the first time an anti-shock packaging model of an acoustic-vibration sensor system has been designed by using the shocking isolation principle. The finite element analysis has been applied for design and simulation of the model. The effects of Young’s modulus of anti-shock rubber on naturally occurring frequencies of the combination of rubber and an acoustic sensor chip were analyzed. The displacement of the acoustic sensor chip is loaded with force. The results of static analysis and harmonic analysis show that while increasing Young’s modulus of anti-chock rubber, the first five natural frequencies of the package body also increases. Yet the displacement of the acoustic sensor chip around the resonant frequency decreases. The results of static and transient analysis show that the displacement of the acoustic sensor chip decreases with the increase of Young’s modulus of anti-chock rubber being loaded with either transient force or static force at the bottom of the combination of rubber and acoustic sensor chip.
基金supported by The National Natural Science Foundation of China(Grant No. 51079092)Specialized Research Fund for the Doctoral Program of Higher Education(Grant no.20090181120088)Science and Technology Support Plan Project of Sichuan Province (Grant No. 2008SZ0163)
文摘Shapai Roller Compacted Concrete(RCC) Arch Dam is the highest RCC arch dam of the 20th century in the world with a maximum height of 132m,and it is the only concrete arch dam near the epicentre of Wenchuan earthquake on May 12th,2008.The seismic damage to the dam and the resistance of the dam has drawn great attention.This paper analyzed the response and resistance of the dam to the seismic wave using numerical simulations with comparison to the monitored data.The field investigation after the earthquake and analysis of insitu data record showed that there was only little variation in the opening size at the dam and foundation interface,transverse joints and inducing joints before and after the earthquake.The overall stability of the dam abutment resistance body was quite good except a little relaxation was observed.The results of the dynamic finite element method(FEM) showed that the sizes of the openings obtained from the numerical modeling are comparable with the monitored values,and the change of the opening size is in millimeter range.This study revealed that Shapai arch dam exhibited high seismic resistance and overload capacity in the Wenchuan earthquake event.The comparison of the monitored and simulated results showed that the numerical method applied in this paper well simulated the seismic response of the dam.The method could be useful in the future application on the safety evaluation of RCC dams.