Using Periodicity to Mitigate Ground Vibration

Abstract

Abstract. Introduction of trenches, barriers and wave impeding blocks on the transmission

Efficiency of Nearly Periodic Structures for Mitigation of Ground Vibration

“…Andersen [1] studied numerous configurations regarding the width of the reference cell, , but in the present work the study will be confined to w1 = 18 m. Further, in the 3D models, the length of the WIBs has as well been taken as 18 m, and the WIBs all have a width of w2 = 2 m. The load is applied on a rigid massless plate with dimensions 18×2 m 2 placed on the ground surface. …”

“…A dispersion diagram may provide an overview of the number of waves that propagate in the structure or medium, but information about attenuated or evanescent modes is lost. As proposed by Andersen [1], a count of different modes occurring at a various frequencies can be presented by a "skyline plot". Using this type of diagram, Figure 4 shows the results obtained for periodic 2D models of a WIB array with different configurations.…”

“…Mead [14] studied the effect of periodicity in a structure, finding that bandgaps occur in certain frequency ranges depending on the mechanical properties of the materials and the geometry of the cell which is repeated along the periodic array. Based on this idea, Andersen [1] proposed the inclusion of periodic structures in the ground to mitigate vibration. Using a two-dimensional FE model and Floquet theory, he demonstrated that stopbands are produced by arrays of WIBs or ground surface changes in the form of small hills and valleys repeated in a periodic manner.…”

Mitigation of Ground Vibrations by Circular Arrays of Rigid Blocks

“…Recently, Van et al [11] developed a methodology to design a one-dimensional wave barrier by topology optimization of a one-dimensional medium. More relevant for the present problem of ground vibration, Persson et al [12] studied the effect of having repeated hills and/or valleys, and Andersen [13] analysed the effect of linear arrays of rigid blocks embedded in the ground using a two-dimensional model of a periodic structure. This work was extended to three-dimensional analysis of nearly-periodic structures [14,15,16].…”