Between Seismology and Seismic Design Prof. Dipartimento di Ingegneria Civile e Ambientale, Politecnico di Milano Milano, 10 dicembre 2013
Outline 2 Seismic hazard analysis for critical facilities SIGMA Project, 2012-2013, 90 k High-performance computing tools to produce physics-based earthquake ground shaking scenarios in large urban areas Contract PoliMi-MunichRE, 2012-2013, 150 k Guidelines for the seismic design of a gas pipeline in Central Italy Contract PoliMi - SNAM Rete Gas, 2013, 128 k Integrated seismic design and assessment of foundations and structures DPC-Reluis Project, 2011-2013 90 k Perspectives for research in Engineering Seismology at Politecnico
The Sigma Project 3 Objective to reduce uncertainties in the different phases of the seismic hazard assessment (SHA) process, with specific care to long return periods of interest for critical industrial facilities. Major topics earthquake catalog assessment improved catalog of seismogenic faults from national to European strong motion databases quantification of uncertainties in the probabilistic SHA accounting for site effects in the PSHA Italian partners: PoliMi, INGV, Università della Basilicata
Probabilistic seismic hazard analysis: input 4 Seismogenic zones Statistical analysis of earthquake catalogs within each zone log N N = Expected number of earthquakes per year with Magnitude > M log N = a -bm M b~ 1 Empirical ground motion prediction equations log PGA M 2 M 1 Distance
Probabilistic seismic hazard analysis: output 5 Seismic hazard map of Italy PGA values with 10% probability of exceedance in 50 years at rock sites (475 yrs return period)
Probabilistic seismic hazard analysis: output 6
Probabilistic seismic hazard analysis: objectives 7 (Macro) Seismic zonation Seismic actions for design
The Sigma Project: contributions of PoliMi 8 (1) Site-specific probabilistic hazard assessment in the Po plain area
The Sigma Project: contributions of PoliMi 9 (1) Site-specific probabilistic hazard assessment in the Po plain area main steps: updated earthquake catalog for improved characterization of the seismogenic sources and models of occurrence application of different Ground Motion Prediction Equations and quantification of uncertainties through a logic tree approach constrain seismic hazard at long return periods by numerical simulations of rare (characteristic) events from seismogenic faults
The Sigma Project: contributions of PoliMi 10 (1) Site-specific probabilistic hazard assessment in the Po plain area UH SA [g] 3 2.5 2 1.5 CAS site, RP 475 yr AB11 (erg) AB11 (non-erg) Fea10 (erg) Fea10 (non-erg) Ita13 (erg) Ita13 (non-erg) Fea10 (erg) ROCK NTC2008 soil C UH SA [g] 3 2.5 2 1.5 CAS site, RP 2475 yr AB11 (erg) AB11 (non-erg) Fea10 (erg) Fea10 (non-erg) Ita13 (erg) Ita13 (non-erg) Fea10 (erg) ROCK NTC2008 soil C UH SA [g] 3 2.5 2 1.5 CAS site, RP 10000 yr AB11 (erg) AB11 (non-erg) Fea10 (erg) Fea10 (non-erg) Ita13 (erg) Ita13 (non-erg) Fea10 (erg) ROCK 1 1 1 0.5 0.5 0.5 0 10-1 10 0 T[s] 0 10-1 10 0 T[s] 0 10-1 10 0 T[s]
The Sigma Project: contributions of PoliMi 11 (2) Assessment of approaches to account for site effects in the PSHA
The Sigma Project: contributions of PoliMi (3) Numerical simulations of earthquake ground motion in the Po plain during the May-June 2012 seismic sequence ~ 8 km 12
The Sigma Project: contributions of PoliMi 13 (3) Numerical simulations of earthquake ground motion in the Po plain during the May-June 2012 seismic sequence M5.9 20/05/2012 M5.8 29/05/2012 Mirandola
The Sigma Project: contributions of PoliMi 14 (3) Numerical simulations of earthquake ground motion in the Po plain during the May-June 2012 seismic sequence May 29, 2012 (M W 6.0)
3D subsoil model for the Po Plain 15 V S Quaternary sediments (Po plain): 300 ( z ) 800 800 15 1500 z 150m V P ( z ) z 500 1800 150 z 500m 1800 z 500 z 500m 1800 ( z ) 2000 2000 0.0725 z 500 30 z 150m Q S ( z ) 80 150 z 500m 80 0.03( z 500) z 500m Miocene formations Quaternary sediments G/Gmax NLE soil behaviour in the top 150 m 1 20 18 0.8 16 14 0.6 Shear Modulus 12 Damping Ratio 10 0.4 8 6 0.2 4 2 0 0 0.0001 0.001 0.01 0.1 1 Shear Strain (%) Damping Ratio (%) -1000-2000 -3000 Milana et al. (2013) z (m) 0-4000 -5000-6000 3D-basin 3D-bedrock -7000 0 1000 2000 3000 4000 V S (m/s)
The Sigma Project: contributions of PoliMi 16 (3) Numerical simulations of earthquake ground motion in the Po plain during the May-June 2012 seismic sequence SD Elements # Numerical simulations in the FERMI supercomputer, CINECA Nodes # t (s) Duration (s) f max (Hz) Walltime (512 cores) 3 1 852 651 50 850 136 0.001 50 ~1.5 ~4.55 h
Verification: comparison with the DWM (Hisada s code) 17 MRN SAN0 RAV0
The Sigma Project: contributions of PoliMi 18 (3) Numerical simulations of earthquake ground motion in the Po plain during the May-June 2012 seismic sequence Quaternary sediments top of Early Pliocene (Messiniano) Mirandola seismic fault 0 2 km 4 km 6 km 8 km
The Sigma Project: contributions of PoliMi 19 (3) Numerical simulations of earthquake ground motion in the Po plain during the May-June 2012 seismic sequence
The PoliMi-MunichRE contract 20 Motivation (1) Recent earthquakes in large urban and industrial areas caused major and unexpected losses for the reinsurance industry 8 costliest earthquake events worldwide
The PoliMi-MunichRE contract 21 Motivation (2) Empirical tools for ground motion prediction equations, that are not well constrained by records of real earthquakes, should be improved by synthetic ground motions based in numerical simulations Magnitude 7 6 5 ITA10_Mw ITA10_Ml Removed data range of potential damage to structures available earthquake records in Italy 4 0.1 1 10 100 Distance [km]
The PoliMi-MunichRE contract 22 Objective to develop an open-source high-performance numerical code for seismic wave propagation analyses and to apply it for the generation of earthquake ground shaking scenarios in large urban areas
The PoliMi-MunichRE contract 23 SPEED web site http://mox.polimi.it/it/progetti/sp eed/speed/people.html SPEED has been selected as one of the emerging applications with industrial relevance within the project PRACE-2IP WP 9.3 (2012-2013)
The PoliMi-MunichRE contract 24 SPEED is an open-source code for the simulation of seismic wave propagation in two- and three-dimensional complex media. SPEED is jointly developed by MOX (The Laboratory for Modeling and Scientific Computing, Department of Mathematics) and DICA (Department of Civil and Environmental Engineering) at Politecnico di Milano. SPEED is a discontinuous Galerkin spectral element code that incorporates the open-source libraries METIS and MPI for the parallel computation (mesh partitioning and message passing). It has been designed with the aim of simulating large-scale seismic events, allowing the evaluation of the typically multi-scale wave propagation problems in its complexity, from far-field to near-field and from near-field to soil-structure interaction effects.
The PoliMi-MunichRE contract 25 The SPEED approach
The PoliMi-MunichRE contract 26 SPEED potential applications Dynamic Soil Structure Interaction Traffic-induced vibrations L Aquila basin Seismic wave propagation in complex geological configurations
The PoliMi-MunichRE contract 27
The PoliMi-MunichRE contract 28 SANTIAGO DEL CILE ~ 5 hours on FERMI using 512 cores
The PoliMi-MunichRE contract 29 Web repository of earthquake ground shaking scenarios
The PoliMi-MunichRE contract 30 Work in progress: Wellington, New Zealand Volume: ~ 50x80x45 km SEs: ~ 350,000 hexahedra (~200,000 SEs in the basin) non-conforming meshing strategy
The PoliMi-MunichRE contract 31 Work in progress: Wellington, New Zealand
The contract PoliMi SNAM Rete gas 32 Objective to prepare guidelines for the seismic design of the Sulmona-Foligno gas pipeline. Major topics overview of technical norms and guidelines in-field investigations ( Zanzi, Lualdi) seismic input ( Paolucci) seismic analysis under transient ground deformation, including dynamic soil-structure interaction ( Perotti, Martinelli) seismic analysis under permanent ground deformation, including slope-stability, liquefaction, fault rupture ( di Prisco, Pergalani, Mariani)
The contract PoliMi SNAM Rete gas 33
The contract PoliMi SNAM Rete gas 34 expected earthquake induced slope displacements along the pipeline (Pergalani & Compagnoni)
The contract PoliMi SNAM Rete gas 35 pipeline subjected to strike-slip fault rupture with increasing fault offsets
The project DPC-RELUIS 36 Software for the design spectrum-compatible selection of real accelerograms (in cooperation with Università Federico II, Napoli) Target spectrum and compatibility bounds. Site definition and reference structural code selection (Italian, European, or S5). Limit state definition for code-based spectrum construction,or be user defined spectrum input. Definition of bins of interest in terms of source, intensity, and site parmeters. Output management and secondary options Choice of how many horizontal components should have each record in the set. Definition of range of periods where the average of the set has to match the target spectrum and matching tolerances. Selection of search for one set only or for multiple sets, and search for original or amplitudescaled records. Choice of set size: one, seven or thirty muticomponent records.
The project DPC-RELUIS 37 Integrated seismic design and assessment of foundations and structures Experimental results
The project DPC-RELUIS 38 Integrated seismic design and assessment of foundations and structures Numerical simulations by a non-linear macro-element model of the foundation
The project DPC-RELUIS 39 Integrated seismic design and assessment of foundations and structures Recent Publications Paolucci R., Figini R., Petrini L. Introducing dynamic non-linear soil foundation-structure interaction effects in displacement-based seismic design. Earthquake Spectra, 29: 475 496, 2013 Ni P., Petrini L., Paolucci R. Direct displacement-based assessment with nonlinear soil structure interaction for multi-span reinforced concrete bridges. Structure and Infrastructure Engineering, in press, 2013. Pecker A., Paolucci R., Chatzigogos C., Correia A., Figini R. The role of non-linear dynamic soil-foundation interaction on the seismic response of structures. Bulletin of Earthquake Engineering, DOI 10.1007/s10518-013-9457-0, 2013.