SOIL: A theoretical manual
A.W.M. Kok, Andrei V. Metrikine, Stanislav Verichev, A Vostroukov · Research Repository (Delft University of Technology) · 2003
A new model for vibration transmission through the soil has been developed.The so called SOIL module has been based upon an application of the Hankel transform method (HTM) and the method of separation of variables (SVM).The application of the new method brings the following advantages.First, the HTM and SVM are purely analytical approaches that have no restrictions concerning wave propagation in the layered soil.Second, the new method has been applied for loads uniformly distributed at small areas.This allows us to build a general solution to the source/receiver problem for any visco-elastic horizontally layered soil structure and for any relative position of the source and receiver, i.e. the "near field" problem is solved now exactly.In the report first, the general statement of the problem is formulated in terms of velocities, forces, and admittance and impedance matrices.Second, the theoretical base for the HTM for the cases of vertical and horizontal loads is presented.Third, the SVM is proposed as an alternative for the HTM at frequencies larger than 30 Hz and the theoretical description of the SVM for the vertical and horizontal loads is given.The reason to use the SVM instead of the HTM at high frequencies consists in that, that the HTM, being an integration routine, has a serious computational drawback.The upper limit of the integral, to be taken numerically, is proportional to the frequency.With the increase of the frequency the calculations loose either computational speed or accuracy.The SVM, being an addition procedure, does not have such a problem.Furthermore, it significantly speeds up the process of calculations.Finally, the numerical simulations of some ING cases such as pile driving, traffic loads and FWD test performed both by the old and new programs are shown and compared to demonstrate essential differences between the obtained results.