1. Department of Geotechnical Engineering Tongji University, Shanghai 200092;
2. Key laboratory of Geotechnical and Underground Engineering (Tongji University), Ministry of Education, Shanghai 200092;
3. China Railway Eryuan Engineering Group East China Survey and Design Co.,Ltd, Zhejiang Hangzhou 310006
Abstract:By double Fourier transform and contour integration technique, a closed-form solution to the steady-state response of a uniform beam placed on Kerr foundation and subjected to a moving harmonic load was obtained. The beam was described as a Euler-Bernoulli beam, and the cut-on frequency and critical velocity of the foundation beam were determined based on the dispersive curve of Kerr foundation beam. The influences of the train speed, load frequency, coefficient of subgrade reaction and foundation shear coefficient on the deflection of foundation beam were investigated and the influence of foundation damping on the critical velocity and resonant frequency was also studied. Moreover, a two-dimensional beam-soil model was established to calculate the deflection of foundation beam under non-moving constant load and simple harmonic load. The numerical results were compared with the analytical solutions of Kerr foundation, Pasternak foundation, and the Winkler foundation. It is concluded that the Kerr foundation model can give best agreement with the FEM results, while the Winkler foundation model presents greatest discrepancy in static calculations. As for dynamic calculation, the time history responses base on different types of foundation beam models are only close to the numerical results at the places near the applied load.
黄强1,2,黄宏伟1,2,张冬梅1,2,黄栩3. 移动简谐荷载作用下Kerr地基梁的稳态响应研究[J]. 振动与冲击, 2018, 37(1): 14-20.
Huang Qiang1,2 Huang Hong-wei1,2 Zhang Dong-mei1,2 Huang Xu3. Steady-state response of an infinite Euler-Bernoulli beam on Kerr foundation subjected to a moving oscillating load. JOURNAL OF VIBRATION AND SHOCK, 2018, 37(1): 14-20.
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