GNGTS 2019 - Atti del 38° Convegno Nazionale

470 GNGTS 2019 S essione 2.2 References Calvi GM, Priestley MJN, Kowalsky MJ; 2007: Displacement based seismic design of structures. Pavia: Iuss Press; CSI; 2019:“SAP2000 Integrated Software for Structural Analysis and Design Computers and Structures Inc., Berkeley, California. Dassault Systèmes. Abaqus, F.E.A. V. 6.12 Computer Software 2015. Providence, RI, USA. European Committee for Standardization (CEN); 2004. Eurocode 8 - Design of structures for earthquake resistance, part 1: general rules, seismic actions and rules for buildings. Brussels, Belgium. Fajfar P, Gaspersic P; 1996. The N2 method for the seismic damage analysis of RC buildings . Earthquake Eng. Struct; D25 , 31-46 pp. Pang WC, Rosowsky DV; 2009. Direct displacement procedure for performance-based seismic design of mid-rise wood-framed structures . Earthquake Spectra; 25 , 583-605 pp. Sciomenta M, Bedon C, Fragiacomo M, Luongo A.;2018. Shear Performance Assessment of Timber Log-House Walls under In-Plane Lateral Loads via Numerical and Analytical Modelling . Buildings, 8(8) 99 pp. The American Society of Civil Engineers; 2016: ASCE/SEI 7-16 - Minimum Design Loads and Associated Criteria for Buildings and Other Structures USA. Table 3 - Comparison between base shear forces and top displacements obtained by Modal-DBD procedure and Push over analysis in Y-direction. Y-direction       Modal DDBD      Push over       Var. [%] BaseShear DispTop BaseShear DispTop BaseShear DispTop [kN] [mm] [kN] [mm] CP 283.0 195.8 283.7 170.9 0.24 12.72 LS 246.0 124.96 246.5 123.0 0.21 1.57 IO 73.0 37.312 75.2 37.5 2.95 -0.50 2D RESONANCE DETECTED WITH H/V MEASUREMENTS G. Sgattoni, G. Lattanzi, S. Castellaro Dipartimento di Fisica e Astronomia, Università di Bologna, Italy Introduction. The H/V method is well known as a tool for seismic microzonation thanks to the correlation observed between the H/V peak frequency and the SH-resonance frequency of the site (e.g. Bard, 1998; Haghshenas et al. , 2008). This also implies its stratigraphic capability, while assuming a 1D planar stratigraphy. In the case of complex geological structures, however, 2D or 3D resonance patterns may develop and the stratigraphic application becomes problematic. This has also important consequences on the evaluation of the seismic site response. While extensive theoretical studies on 2D resonance already exist (e.g. Bard and Bouchon, 1985; Chávez-García et al. , 2000), only a small number of studies include actual observation of the phenomenon, e.g. in the Rhône valley (Roten et al. , 2006) and in the Romanche valley (Le Roux et al. , 2012). Sediment-filled valleys are typical examples of geological structures where 2D resonance can occur. In the framework of a study to map the depth to bedrock in the Bolzano sedimentary basin, we collected 60 H/V measurements across the basin and identified evidences of 2D resonance effects. The Bolzano sedimentary basin has a complex morphology because it lies at the intersection between the 2-3 km wide Adige valley on the western and southern sides and two minor tributary valleys on the northern and eastern sides (Fig. 1). Previous deep stratigraphic information is known only from two seismic reflection profiles, one of which of