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The paper deals with the approaches to the response analysis of large transport and lifeline structures. The background theory for simplified analysis is presented. Seismic inputs represent the cases of explosion impacts and large near field earthquake effects. 3DOF and 6DOF input models are based on surface wave theory and applied for calculations and shaking table experiments. Examples of seismic motion simulations are those obtained during large MASTER shaking table tests in Enel.Hydro-ISMES Seriate, Italy in the framework of EC international projects.

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Guided waves play important role in the investigation of near surface geological structures. As it is well-known guided waves contain information about the structural- and material parameters of the wave-guide model, so - using the methods of geophysical inversion - these characteristics can be determined by means of the frequency-dependent phase- and group velocity as well as absorption coefficient data. In this paper the approximate horizontal inversion method (Dobróka 1996) is combined with a seismic tomography procedure in order to reconstruct the 3D geometry of the wave-guide structure by means of dispersion data (group traveltimes) of the guided surface waves. The inversion procedure consists of two steps: first the local group velocities are determined at various frequencies by means of tomographic inversion of the group traveltimes, the local dispersion characteristics of the Love- or Rayleigh surface waves are then inverted in the second step. In our investigations a robust SIRT method (Dobróka 1996) is used for tomography and a simple Least Squares algorithm is applied for the inversion of the group velocity data.

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In the small seismic source zone of Kecskemét 203 earthquakes are known between 1739 and 2006, and about 90 percent of them have a magnitude value not more than 3.0, however the strongest event on July 8, 1911 has 5.6 surface-wave magnitude. Concerning the latter earthquake the maximum (epicentral) intensity I = VIII (EMS) was observed in the area enclosed by Kecskemét, Katonatelep and Hetényegyháza locations. The quake caused significant damage to buildings (I ≥ VI EMS) on about 6 thousands square kilometres and was felt (I ≥ III EMS) on some 85 thousands square kilometres. The focal depth is estimated as 11 km directly from the individual intensity data points. During the earthquake liquefaction (sand crater) occurred in the epicentral area and some electromagnetic effects were also observed. Studying the source dimensions we conclude the rupture area is between 40 and 67 square kilometres and the maximum displacement along the fault is estimated to 14–20 centimetres for the Kecskemét earthquake of July 8, 1911. A probabilistic seismic hazard assessment predicts 1.1–1.5 m/s 2 peak ground accelerations, and 6.6–7.1 maximum (theoretical) earthquake intensity values with 10% chance of exceedance for an exposure time of 100 years in the studied area.

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In the region of the Carpathian-Pannonian Basin (44–50N; 13–28E) 81 earthquakes have moment magnitude (M w); 61 of them are crustal events (focal depth <65 km) while 20 earthquakes belong to the intermediate focal depth region of the Vrancea (Romania) zone. For crustal events the regression of moment magnitude (M w) on local magnitude (M l) shows a better fit for large magnitudes using a second order equation against to a linear relationship, and the actual quadratic formula based on 61 events is the following: \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $\begin{gathered} M_w = 1.37( \pm 0.28) + 0.39( \pm 0.18)M_l + 0.061( \pm 0.026)M_l^2 \hfill \\ (M_w :1.9 - 5.5;M_l :1.4 - 5.5). \hfill \\ \end{gathered} $ \end{document}.In the intermediate focal depth Vrancea zone of the south-eastern bend of the Carpathians (44.5–46.5N; 25.5–28.0E) the number of body wave magnitudes is the largest one (20) among the local (8), the surface wave (14) and the duration (17) magnitudes. The linear relationship between the moment (M w) and the body wave (M b) magnitudes has the following form: \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $M_w = 1.20( \pm 0.08)M_b - 0.76( \pm 0.40)(M_w :4.1 - 7.7;M_b :3.8 - 7.3).$ \end{document}.The relationships of the different (M l, M s, M b, M d) magnitudes are also presented in the paper.

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Bassin C, Laske G, Masters G 2000: The Current Limits of Resolution for Surface Wave Tomography in North America, EOS Trans AGU, 81, F897 Masters G. The Current Limits of Resolution for

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Pollack Periodica
Authors: Mykola Sysyn, Vitalii Kovalchuk, Ulf Gerber, Olga Nabochenko, and Andriy Pentsak

] Sussmann T. R. , Thompson , H. B. , Stark , T. D. , Wilk , S. T. , Ho C. L. Use of seismic surface wave testing to assess track substructure condition , Construction and Building Materials , Vol. 155

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.1023/B:RUNT.0000009071.94892.15 [6] Y. Fan , S. Dixon , R. S. Edwards , and X. Jian , “ Ultrasonic surface wave propagation and interaction with surface defects on rail track head ,” NDT & E Int. , vol. 40 , pp. 471 – 477 , 2007 . 10.1016/j

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. This pressure generates multiple waves such as dilatational waves and shear waves propagating in the bulk of the solid as well as surface waves. For frequencies sufficiently high, the dilatational waves can be modelled by Rayleigh–Sommerfeld like

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