Dynamic interaction analysis of vehicle-bridge system using transfer matrix method

Tianyu Xiang,Renda Zhao 국제구조공학회 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.20 No.1

The dynamic interaction of vehicle-bridge is studied by using transfer matrix method in this paper. The vehicle model is simplified as a spring-damping-mass system. By adopting the idea of Newmark-β method, the partial differential equation of structure vibration is transformed into a differential equation irrelevant to time. Then, this differential equation is solved by transfer matrix method. The prospective application of this method in real engineering is finally demonstrated by several examples.

Dynamic analysis of thin-walled open section beam under moving vehicle by transfer matrix method

Xiang, Tianyu,Xu, Tengfei,Yuan, Xinpeng,Zhao, Renda,Tong, Yuqiang Techno-Press 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.30 No.5

Three dimensional coupled bending-torsion dynamic vibrations of thin-walled open section beam subjected to moving vehicle are investigated by transfer matrix method. Through adopting the idea of Newmark-${\beta}$ method, the partial differential equations of structural vibration can be transformed to the differential equations. Then, those differential equations are solved by transfer matrix method. An iterative scheme is proposed to deal with the coupled bending-torsion terms in the governing vibration equations. The accuracy of the presented method is verified through two numerical examples. Finally, with different eccentricities of vehicle, the torsional vibration of thin-walled open section beam and vertical and rolling vibration of truck body are investigated. It can be concluded from the numerical results that the torsional vibration of beam and rolling vibration of vehicle increase with the eccentricity of vehicle. Moreover, it can be observed that the torsional vibration of thin-walled open section beam may have a significant nonlinear influence on vertical vibration of truck body.

Dynamic interaction analysis of vehicle-bridge system using transfer matrix method

Xiang, Tianyu,Zhao, Renda Techno-Press 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.20 No.1

The dynamic interaction of vehicle-bridge is studied by using transfer matrix method in this paper. The vehicle model is simplified as a spring-damping-mass system. By adopting the idea of Newmark-${\beta}$ method, the partial differential equation of structure vibration is transformed into a differential equation irrelevant to time. Then, this differential equation is solved by transfer matrix method. The prospective application of this method in real engineering is finally demonstrated by several examples.

Dynamic analysis of thin-walled open section beam under moving vehicle by transfer matrix method

Tianyu Xiang,Tengfei Xu,Xinpeng Yuan,Renda Zhao,Yuqiang Tong 국제구조공학회 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.30 No.5

Three dimensional coupled bending-torsion dynamic vibrations of thin-walled open section beam subjected to moving vehicle are investigated by transfer matrix method. Through adopting the idea of Newmark-β method, the partial differential equations of structural vibration can be transformed to the differential equations. Then, those differential equations are solved by transfer matrix method. An iterative scheme is proposed to deal with the coupled bending-torsion terms in the governing vibration equations. The accuracy of the presented method is verified through two numerical examples. Finally, with different eccentricities of vehicle, the torsional vibration of thin-walled open section beam and vertical and rolling vibration of truck body are investigated. It can be concluded from the numerical results that the torsional vibration of beam and rolling vibration of vehicle increase with the eccentricity of vehicle. Moreover, it can be observed that the torsional vibration of thin-walled open section beam may have a significant nonlinear influence on vertical vibration of truck body.

Nonlinear finite element analysis of circular concrete-filled steel tube structures

Xu, Tengfei,Xiang, Tianyu,Zhao, Renda,Zhan, Yulin Techno-Press 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.35 No.3

The structural behaviors of circular concrete filled steel tube (CFT) structures are investigated by nonlinear finite element method. An efficient three-dimensional (3D) degenerated beam element is adopted. Based on those previous studies, a modified stress-strain relationship for confined concrete which introduces the influence of eccentricity on confining stress is presented. Updated Lagrange formulation is used to consider the geometrical nonlinearity induced by large deformation effect. The nonlinear behaviors of CFT structures are investigated, and the accuracy of the proposed constitutive model for confined concrete is mainly concerned. The results demonstrate that the confining effect in CFT elements subjected to combining action of axial force and bending moment is far sophisticated than that in axial loaded columns, and an appropriate evaluation about this effect may be important for nonlinear numerical simulation of CFT structures.

Nonlinear finite element analysis of circular concrete-filled steel tube structures

Tengfei Xu,Tianyu Xiang,Renda Zhao,Yulin Zhan 국제구조공학회 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.35 No.3

The structural behaviors of circular concrete filled steel tube (CFT) structures are investigated by nonlinear finite element method. An efficient three-dimensional (3D) degenerated beam element is adopted. Based on those previous studies, a modified stress-strain relationship for confined concrete which introduces the influence of eccentricity on confining stress is presented. Updated Lagrange formulation is used to consider the geometrical nonlinearity induced by large deformation effect. The nonlinear behaviors of CFT structures are investigated, and the accuracy of the proposed constitutive model for confined concrete is mainly concerned. The results demonstrate that the confining effect in CFT elements subjected to combining action of axial force and bending moment is far sophisticated than that in axial loaded columns, and an appropriate evaluation about this effect may be important for nonlinear numerical simulation of CFT structures.

Effect of impurity components in stainless steel dust on the coloring properties of the prepared black ceramic pigments

Zhiqiao Li,Xiang Zhang,Guojun Ma,Dingli Zheng,Ruixiang He,Tianyu Du 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.1

Stainless steel dust (SSD) can be utilized as the primary raw material for the production of Fe-Cr-Ni-Mn system black ceramicpigments because it is high in transition metal elements. However, in addition to the ingredients required for the preparationof black pigments, it also contains some impurity elements like Ca, Mg, Si and Zn, and the influence of these impurity elementson the coloring performance of the pigments is unclear. In this paper, pure chemical reagents were used as raw materials tosimulate the main components of SSD for the solid-phase synthesis of black ceramic pigments doped with various impuritycomponents (CaO, MgO, SiO2 and ZnO). The results show that the doping of MgO can improve the purity of the preparedblack ceramic pigments, whereas CaO, SiO2 and ZnO can turn the pigments become reddish yellow. In the doped samples,ZnO and MgO mainly react with Fe2O3 to form ZnFe2O4 and MgFe2O4. In addition, CaO reacts with Fe2O3 to generateCaFe4O7. The reactions described above can increase the average crystallite size and distort the crystal lattice of the crystalsin the pigment samples. Moreover, SiO2 exists in amorphous form among spinel grains.

Long Non-coding RNA CASC15 Promotes Intrahepatic Cholangiocarcinoma Possibly through Inducing PRDX2/PI3K/AKT Axis

Yuan Zhang,Lufei Zhang,Sinan Lu,Yucheng Xiang,Cheng Zeng,Tianyu He,Yuan Ding,Weilin Wang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.1

Purpose Intrahepatic cholangiocarcinoma (ICC) is one of the most common liver primary tumors but its treatments are limited. Bioinformatics showed that the expression level of long non-coding RNA cancer-associated susceptibility 15 gene (CASC15) is correlated with ICC progression, but its functional mechanism remains unclear. Materials and Methods Tissues from ICC patients, tumor and adjacent tissue, were used for detection of the expression of CASC15. Clinical data were also collected for clinicopathologic and survival analysis. Short interfering RNA and lentiviral short hairpin RNA were used to knock down CASC15 and PRDX2 expression in ICC cell lines, for the analysis of changes of cell function and xenografts. RNA-pulldown and RNA immunoprecipitation assays were used to detect RNA-binding protein, PRDX2. Male nude mice were used for ICC xenografts, and livers were collected after 4 weeks for immunohistochemistry. Results CASC15 is highly expressed in ICC tissues and is related to higher TNM stage. Knockdown of CASC15 in ICC cells reduced cell proliferation, migration, invasiveness and increased apoptosis, and G1/S block. PRDX2 bound to CASC15. Knockdown of CASC15 decreased PRDX2 expression which was rescued by the inhibition of proteasome formation. Downregulation of PRDX2 resulted in G1/S block, reduced ICC cell invasion. Downregulation of CASC15 inhibited phosphoinositide 3-kinase (PI3K)/AKT/c-Myc pathway through downregulating of PRDX2 and overexpressed PRDX2 rescued the block. CASC15 knockout in ICC xenografts suppressed tumor development in vivo, decreased the expression of PRDX2 and Ki67 and inhibited PI3K/AKT pathway. Conclusion CASC15 promotes ICC possibly by targeting PRDX2 via the PI3K/AKT pathway, indicating poor prognosis and high degree of malignancy of ICC.

Case study of random vibration analysis of train-bridge systems subjected to wind loads

Siyu Zhu,Yongle Li,Koffi Togbenou,Chuanjin Yu,Tianyu Xiang 한국풍공학회 2018 Wind and Structures, An International Journal (WAS Vol.27 No.6

In order to reveal the independent relationship between track irregularity and wind loads, the stochastic characteristics of train-bridge coupling systems subjected to wind loads were investigated by the multi-sample calculation. The vehicle was selected as 23 degrees of freedom dynamical model, and the bridge was described by three-dimensional finite element model. It was assumed that the wind loads were random processes with strong spatial correlation, while the track irregularities were stationary random ones. As a case study, a high-speed train running on a cable-stayed bridge subjected to wind loads was studied. The effect of rail irregularities was deemed to be independent of the effect of wind excitations on the coupling system in the same wind circumstance for the same project, leading to the conclusion that the effect of wind loads and moving vehicle could be calculated separately. The variance results of the stochastic responses of vehicle-bridge coupling system under the action of wind loads and rail irregularities together were equivalent to the sum of the variance of the responses induced by each excitation. Therefore, when one of the input excitations is different, only the effect of changed loads needs to be assessed. Moreover, the new calculated results were combined with the effect of unchanged loads to present the stochastic response of coupling system subjected to the different excitations, reducing the cost of computations. The stochastic characteristics, the CFD (cumulative distribution function) of the coupling system with different wind velocities, vehicle speed, and vehicle marshalling were studied likewise.