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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring Real-time seismic vulnerability assessment of a high rise RC building using field monitoring data Istanbul, August 24-29, 2014 Sotiria Karapetrou Maria Manakou Despoina Lamprou Sofia Kotsiri Kyriazis Pitilakis Aristotle University of Thessaloniki

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 2 Aim of this study: real-time seismic vulnerability assessment of RC building using field monitoring data reflecting the actual state of the structure (degradation due to time, possible pre-existing damage, changes in geometry and mass distribution etc.) EU project REAKT (Strategies and Tools for Real Time EArthquake RisK ReducTion): Rapid post-earthquake assessment of buildings based on field monitoring data Target structure: high-rise RC hospital building in Thessaloniki Introduction

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 3 Methodological framework Fragility assessment of buildings using field monitoring data Finite element modeling (FEM) Operational modal analysis (OMA) Evaluation of MAC values Comparison between numerical and experimental modes Finite element model updating Sensitivity in material properties Selection of the best FE model Nonlinear incremental dynamic analysis Derivation of real time fragility curves

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 4 Description of the hospital building in Thessaloniki AHEPA Hospital complex Target building Target building: high-rise (8-storey) RC infilled MRF structure designed with low seismic code level (SYNER-G taxonomy). It hosts both administration and hospitalization activities. It is composed of two adjacent tall building units that are connected with a structural joint The foundation consists of simple footings without tie-beams combined partially with a raft foundation.

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 5 RC buildingsTotal mass (t)f c (MPa)f y (MPa)f m (MPa) UNIT 13719.014.0220.0 and 500.03.0 UNIT 23112.014.0220.0 and 500.03.0 Description of the hospital building

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 6 Temporary instrumentation array 36 triaxial seismometers: Mark short-period seismometers (L4C-3D, 1Hz natural frequency) EarthData recorders EDL (PR6-24) February 2013: ambient noise measurements (AUTH, GFZ) North South (NS) longitudinal direction of the structure NS 4 hour recordings Sampling rate 500Hz 4 stations at each floor installed along the middle corridor of the building near and far the structural joint. UNIT 1UNIT 2 Basement UNIT 1 UNIT 2 4th floor UNIT 1UNIT 2 Top floor

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring UNIT 1UNIT 2 Basement 7 Temporary instrumentation array Section A-A Structural joint between the building UNITS UNIT 1 UNIT 2 AAA

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 8 System identification and Operational modal analysis () MACEC 3.2 software (Reynders et al. 2011) OMA for the two adjacent building units separately (UNIT 1 and UNIT 2) and for the entire hospital building analyzed as one (BUILDING). Grid of the models: the defined nodes correspond to the nodes that are measured. Non-parametric and parametric identification techniques are applied. Non-parametric: Frequency Domain Decomposition FDD (Brincker et al. 2001) Parametric: Stochastic Subspace Identification SSI (Van Overschee and De Moor 1996)

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 9 System identification and Operational modal analysis Frequency Domain Decomposition FDD Singular values Stochastic Subspace Identification SSI Stabilization diagrams

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 10 ModeMode type UNIT 1UNIT 2BUILDING FDD (Hz) SSI (Hz, %) FDD (Hz) SSI (Hz, %) FDD (Hz) SSI (Hz, %) 1 Coupled translational 1.65 0.81.65 0.91.65 0.8 2 Coupled translational 1.901.911.31.91 1.11.91 0.8 3Torsional2.33 3.62.352.333.52.352.333.2 41 st Longitudinal3.503.475.43.583.525.83.583.516.4 52 nd Longitudinal5.205.153.05.225.161.15.205.152.1 Modal identification results for UNIT 1, UNIT 2 and BUILDING estimated using parametric (SSI) and non-parametric (FDD) identification techniques System identification and Operational modal analysis

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 11 Finite element model updating Initial elastic numerical model of the building units: based on the design and documentation plans provided by the Technical Service of the hospital. numerical modeling conducted in OpenSees (Mazzoni et al. 2009) separately for UNIT 1 and UNIT 2 Elastic beam-column elements to model the RC elements (beam and columns) Elastic truss elements to model the masonry infills: double strut model to represent the in plane behavior of the infill panel. Fixed base conditions are assumed for both building units

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 12 Finite element model updating Masonry compressive strength values calculated based on the mean and standard deviation values of the normal distribution adopted with: Sensitivity parameter: compressive strength of the masonry infill f m Normal distribution for f m (Mosalam et al. 1997) mean value =3MPa covariance COV=20% -3s f m +3s, s: standard deviation Elastic modulus in compression of masonry infills computed based on compressive strength: E m = 1000f m (Paulay and Priestley 1992)

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 13 Finite element model updating Selection of the best model based on MAC values (MAC>0.8) E mlong1 = 3GPa (fm==3MPa) E mlong2 =1.8GPa (fm=-2=1.8MPa) E mtransv1 =3GPa (fm= =3MPa) E mtransv2 =4.8GPa (fm=+3=4.8MPa) Evaluation of modal assurance criterion MAC values regarding the correlation between numerical and experimental modes and the selection of the best updated model j eigenvector j from numerical model Ei eigenvector i from field monitoring test E mlong1 E mtransv1 E mlong1 E mlong2 E mtransv2 E mtransv1 Optimal scenario

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 14 Finite element model updating UNIT 1 Initial FEM T (sec)/f(Hz) Mode shape of updated FEM T (sec)/f(Hz) Mode shape of experimental model T(sec)/f(Hz) MAC Coupled translational T 1 =0.69sec/f 1 =1.46Hz 0.96 T 1 =0.64sec/f 1 =1.56HzT 1 =0.61sec/f 1 =1.65Hz Coupled translational T 2 =0.48sec/f 2 =2.06Hz 0.94 T 2 =0.53sec/f 2 =1.89HzT 2 =0.52sec/f 2 =1.91Hz Torsional T 3 =0.37sec/f 3 =2.66Hz 0.97 T 3 =0.37sec/f 3 =2.70HzT 3 =0.43sec/f 3 =2.33Hz

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Laboratory of Soil Mechanics, Foundations and Geotechnical Earthquake Engineering, AUTH Real-time seismic vulnerability assessment of a high rise RC building using field monitoring 15 Finite element model updating UNIT 2 Initial FEM T (sec)/f(Hz) Mode shape of updated FEM T (sec)/f(Hz) Mode shape of experimental model T(sec)/f(Hz) MAC Coupled translational T 1 =0.67sec/f 1 =1.50Hz 0.98 T 1 =0.65sec/f 1 =1.54HzT 1 =0.61sec/f 1 =1.65Hz Coupled translational T 2 =0.49sec/f 2 =2.05Hz