Dynamic response of a three-beam system with intermediate elastic connections under a moving load/mass-spring

• Published in: Earthquake Engineering and Engineering Vibration Vol. 19; no. 2; pp. 377 - 395
• Main Authors: Yulin, Feng, Lizhong, Jiang, Wangbao, Zhou
• Format: Journal Article
• Language: English
• Published: Harbin Institute of Engineering Mechanics, China Earthquake Administration 01.04.2020; Springer Nature B.V; National Engineering Laboratory for High Speed Railway Construction, Central South University, Changsha 410075, China; School of Civil Engineering, Central South University, Changsha 410075, China
• Subjects: Acceleration; Civil Engineering; Control; Differential equations; Dynamic response; Dynamical Systems; Earth and Environmental Science; Earth Sciences; Fourier transforms; Geotechnical Engineering & Applied Earth Sciences; Mass; Mathematical analysis; Moving loads; Ordinary differential equations; Partial differential equations; Spring; Vertical loads; Vibration; mass-spring; critical speeds; finite Sine-Fourier transform; three-beam system; moving load
• ISSN: 1671-3664; 1993-503X
• DOI: 10.1007/s11803-020-0568-8

The objective of this research is to study the dynamic response characteristics of a three-beam system with intermediate elastic connections under a moving load/mass-spring. In this study, the finite Sine-Fourier transform was performed for the dynamic partial differential equations of a simply supported three-beam system (SSTBS) under a moving load and a moving mass-spring, respectively. The dynamic partial differential equations were transformed into dynamic ordinary differential equations relative to the time coordinates, and the equations were solved and the displacement Fourier amplitude spectral expressions were obtained. Finally, based on finite Sine-Fourier inverse transform, the expressions for dynamic response of SSTBS under the moving load and moving mass-spring were obtained. The proposed method, along with ANSYS, was used to calculate the dynamic response of the SSTBS under a moving load/mass-spring at different speeds. The results obtained herein were consistent with the ANSYS numerical calculation results, verifying the accuracy of the proposed method. The influence of the load/mass-spring’s moving speed on the dynamic deflections of SSTBS were analyzed. SSTBS has several critical speeds under a moving load/mass-spring. The vertical acceleration incurred by a change in the vertical speed of SSTBS due to the movement of mass-spring and the centrifugal acceleration produced by the movement of massspring on the vertical curve generated by SSTBS vibration could not be neglected.