Article : A Numerical Study of Effects of Valley-Weathering and Valley-Shape-Ratio on the Ground Motion Characteristics
Authors : Karakostas, V.Geophysics Department, Aristotle University of Thessaloniki, Thessaloniki, Greece, email@example.com, Papadimitriou, E.Geophysics Department, Aristotle University of Thessaloniki, Thessaloniki, Greece, firstname.lastname@example.org, Mesimeri, M.Geophysics Department, Aristotle University of Thessaloniki, Thessaloniki, Greece, email@example.com, Paradisopoulou, P.Geophysics Department, Aristotle University of Thessaloniki, Thessaloniki, Greece, firstname.lastname@example.org, Gkarlaouni, Ch.Geophysics Department, Aristotle University of Thessaloniki, Thessaloniki, Greece, email@example.com, Trojanowski, J.Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland, firstname.lastname@example.org, Plesiewicz, B.Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland, Wiszniowski, J.Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland, Danek, T.Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, Canad, Slawinski, M. A.Department of Geoinformatics and Applied Computer Science, AGH – University of Science and Technology, Kraków, Poland, Baddari, K.Laboratory of Physics of the Earth UMBB, Boumerdes, Algeria / University of Bouira, Bouira, Algeria / Laboratory LIMOSE UMBB, Boumerdes, Algeria, Frolov, A. D.Geophysical Division NCG, Russian Academy of Sciences, Moscow, Russia, Tourtchine, V.Laboratory LIMOSE UMBB, Boumerdes, Algeria, Rahmoune, F.Laboratory LIMOSE UMBB, Boumerdes, Algeria, Makdeche, S.Laboratory LIMOSE UMBB, Boumerdes, Algeria, Semenov, V. Yu.Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland, email@example.com, Giorgi, L.IBAM – National Council of Research, Lecce, Italy, Leucci, G.IBAM – National Council of Research, Lecce, Italy, Narayan, J. P.Department of Earthquake Engineering, Indian Institute of Technology Roorkee, Roorkee, India, Arafat, M. Y.Department of Earthquake Engineering, Indian Institute of Technology Roorkee, Roorkee, India, KamalDepartment of Earthquake Engineering, Indian Institute of Technology Roorkee, Roorkee, India,
Abstract : A study of combined effects of valley-weathering and valley-shaperatio on the ground motion characteristics and associated differential ground motion (DGM) is documented in this paper. In order to properly quantify the weathering effects, a forth-order-accurate staggered-grid viscoelastic time-domain finite-difference program has been used for the simulation of SH-wave responses. Simulated results revealed that the defocusing caused by valley is frequency-independent in contrast to the ridge-focusing. A decrease of average spectral amplification (ASA) with an increase of shape-ratio of the non-weathered triangular and elliptical valleys was obtained. Overall, the amplification and de-amplification pattern was larger in case of triangular valleys as compared to the elliptical valleys. It can be concluded that the dwelling within or near the topcorners of weathered valleys may suffer more damage as compared to their surroundings. A weathered triangular valley with large shape-ratio may cause unexpected damage very near its top-corners since both the ASA and DGM are largest.
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Qute : Karakostas, V. ,Papadimitriou, E. ,Mesimeri, M. ,Paradisopoulou, P. ,Gkarlaouni, Ch. ,Trojanowski, J. ,Plesiewicz, B. ,Wiszniowski, J. ,Danek, T. ,Slawinski, M. A. ,Baddari, K. ,Frolov, A. D. ,Tourtchine, V. ,Rahmoune, F. ,Makdeche, S. ,Semenov, V. Yu. ,Giorgi, L. ,Leucci, G. ,Narayan, J. P. ,Arafat, M. Y. ,Kamal ,Kamal , A Numerical Study of Effects of Valley-Weathering and Valley-Shape-Ratio on the Ground Motion Characteristics. Acta Geophysica Vol. 63, no. 1/2015