Dynamic response of graded non-homogeneous soil under a moving load
【Abstract】Combined with the coordinate transformation, the dynamic governing equation for graded non-homogeneous soil foundation under a moving load is established. Applying the reverberation ray matrix method, we can derive the expression of displacement and stress in the frequency domain. Assuming that the material properties of graded soil have an exponential law distribution along the thickness-coordinate, with numerical inverse Fourier transformation, the displacement and the stress is obtained. Through numerical examples, the influence of inhomogeneity and load moving velocity on dynamic response of graded non-homogeneous soil is analyzed. The results show that the dynamic responses of inhomogeneous soil are significantly different from those of homogeneous soil. Under a moving load, the vertical displacement of homogeneous soil increases with the rise of the load moving velocity but has a little influence on the vertical displacement of graded non-homogeneous soil.
【Keywords】 dynamic response; graded non-homogeneous; moving load; reverberation ray matrix method; elastic foundation;
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