Numerical Development of a Strengthened Wall-to-Diaphragm Seismic Connection: Calibration and Application on a Building Prototype

Abstract

Effective wall-to-floor connections are crucial components of historical buildings to avoid dangerous mechanisms under seismic actions. Existing buildings often present poor friction-based links between timber floor and masonry wall and are not able to ensure the so called “box behavior”, necessary for the correct distribution of seismic forces. Nonlinear static analysis is one of the most common tools for the seismic assessment of unreinforced masonry buildings considering advanced nonlinear materials description and allowing for different approaches. The selection of a proper control node, for the definition of the pushover curve, is fundamental and sometimes controversial. Moreover, connections are modelled as simply fixed or absent at all. Dynamic nonlinear analysis seems preferable even suffering from a higher computational effort. On the bases of previous experimental campaign developed at the University of Minho, the pull out behavior of a strengthened and unstrengthened masonry-to-timber connection was simulated numerically using OpenSees software. The connection model considers strength degradation and pinching, in agreement with the experimental behavior, and is validated from the energetic point of view, suitable for being included in a global finite element model to study the influence of the hysteretic energy dissipated within the connections on the overall seismic response. This paper describes the calibration process and the application of the connection model into a unreinforced masonry prototype using nonlinear dynamic analysis under real seismic inputs. Both strengthened and unstrengthened configurations are implemented and results compared. The selected model is part of the blind prediction competition organised within the SERA-AIMS project involving the shaking table test of a half-scaled aggregate.

Full document

References

[1] M. Tomaževič, Earthquake-Resistant Design of Masonry Buildings, Imperial College Press, London, UK, 1999. https://doi.org/10.1142/9781848160835.

[2] J. Bothara, S. Brzev, A Tutorial: Improving the Seismic Performance of Stone Masonry Buildings, First Edit, Earthquake Engineering Research Institute, Oakland, California, United States of America, 2011.

[3] J. Ortega, G. Vasconcelos, H. Rodrigues, M. Correia, Assessment of the influence of horizontal diaphragms on the seismic performance of vernacular buildings, Bull. Earthq. Eng. (2018). https://doi.org/10.1007/s10518-018-0318-8.

[4] J. Scacco, N. Bianchini, N. Mendes, C. Cullimore, L. Jain, Seismic assessment of the Church of Carmo Convent, Congr. Métodos Numéricos Em Eng. (2019).

[5] I.E. Senaldi, G. Magenes, A. Penna, A. Galasco, M. Rota, The effect of stiffened floor and roof diaphragms on the experimental seismic response of a full-scale unreinforced stone masonry building, J. Earthq. Eng. 18 (2014) 407–443. https://doi.org/10.1080/13632469.2013.876946.

[6] B. Pantò, F. Cannizzaro, S. Caddemi, I. Caliò, 3D macro-element modelling approach for seismic assessment of historical masonry churches, Adv. Eng. Softw. 97 (2016) 40– 59. https://doi.org/10.1016/j.advengsoft.2016.02.009.

[7] C. Casapulla, A. Maione, L.U. Argiento, Seismic analysis of an existing masonry building according to the multi-level approach of the italian guidelines on cultural heritage, Ing. Sismica. 34 (2017) 40–59.

[8] C. Casapulla, L.U. Argiento, Non-Linear Kinematic Analysis of Masonry Walls Out-of Plane Loaded. the Comparative Role of Friction Between Interlocked Walls, Proc. 6th Int. Conf. Comput. Methods Struct. Dyn. Earthq. Eng. (COMPDYN 2015). (2017) 2301– 2311. https://doi.org/10.7712/120117.5568.18332.

[9] Italian Ministry of Infrastructure and Transport, NTC 2018 - D.M. 17.01.18: Aggiornamento delle “Norme Tecniche per le costruzioni,” (2018) 1–198.

[10] C. Casapulla, L. Cascini, F. Portioli, R. Landolfo, 3D macro and micro-block models for limit analysis of out-of-plane loaded masonry walls with non-associative Coulomb friction, Meccanica. 49 (2014) 1653–1678. https://doi.org/10.1007/s11012-014-9943-8.

[11] O. AlShawa, D. Liberatore, L. Sorrentino, Dynamic One-Sided Out-Of-Plane Behavior of Unreinforced-Masonry Wall Restrained by Elasto-Plastic Tie-Rods, Int. J. Archit. Herit. 00 (2019) 1–18. https://doi.org/10.1080/15583058.2018.1563226.

[12] L. Giresini, M. Fragiacomo, M. Sassu, Rocking analysis of masonry walls interacting with roofs, Eng. Struct. 116 (2016) 107–120.

[13] F. Solarino, D. V Oliveira, L. Giresini, Wall-to-horizontal diaphragm connections in historical buildings: a state-of-the-art review, Eng. Struct. (2019).

[14] S.M.T. Moreira, Seismic retrofit of masonry-to-timber connections in historical constructions, Universidade do Minho, 2015.

[15] M. Collins, B. Kasal, P. Paevere, G.C. Foliente, Three-dimensional model of light frame wood buildings. II: Experimental investigation and validation of analytical model, J. Struct. Eng. 131 (2005) 684–692. https://doi.org/10.1061/(ASCE)0733- 9445(2005)131:4(684).

[16] G. Rinaldin, C. Amadio, M. Fragiacomo, A component approach for the hysteretic behaviour of connections in cross-laminated wooden structures, Earthq. Eng. Struct. Dyn. 42 (2013) 2023–2042. https://doi.org/10.1002/eqe.2310.

[17] H. Isoda, S. Tesfamariam, Connections for Timber–Concrete Hybrid Building: Experimental and Numerical Model Results, J. Perform. Constr. Facil. 30 (2016) 04016024. https://doi.org/10.1061/(asce)cf.1943-5509.0000849.

[18] American Society of Civil Engineers (ASCE), ASCE/SEI 41-13 : Seismic evaluation and retrofit of existing buildings, 2013.

[19] EN 1998-3, Eurocode 8: Design of structures for earthquake resistance - Part 3: Assessment and retrofitting of buildings, 2005.

[20] American Society of Civil Engineers (ASCE), Structural Engineering Institute (SEI), ASCE/SEI 41-17 Seismic Evaluation and Retrofit of Existing Buildings, American Society of Civil Engineers, Reston, Virginia, 2017. https://doi.org/10.1061/9780784414859.

[21] G.L. Fenves, ZeroLength Element, Univ. Texas, Austin. (2014). https://opensees.berkeley.edu/wiki/index.php/ZeroLength_Element (accessed January 20, 2020).

[22] F. McKenna, G.L. Fenves, F.C. Filippou, M. Scott, Open system for earthquake engineering simulation (OpenSees), (2000). http://opensees.berkeley.edu.

[23] K. Bayer, I. Tomic, A. Penna, M. Dejong, C. Butenweg, SERA Project: Seismic Testing of Adjacent Interacting Masonry Structures (AIMS), (2019). http://sera-aims.com/.

[24] R. Faria, J. Oliver, M. Cervera, A strain-based plastic viscous-damage model for massive concrete structures, Int. J. Solids Struct. (1998). https://doi.org/10.1016/S0020-7683(97)00119-4.

[25] E. Arash, E. Zaghi, M. Cashany, ZeroLengthImpact3D, Univ. Connect. (2014). https://opensees.berkeley.edu/wiki/index.php/ZeroLengthImpact3D (accessed January 20, 2020).

[26] C. Casapulla, F. Portioli, Experimental tests on the limit states of dry-jointed tuff blocks, Mater. Struct. Constr. 49 (2016) 751–767. https://doi.org/10.1617/s11527-015-0536-3.

[27] G. Vasconcelos, P.B. Lourenço, D. Oliveira, Experimental shear behavior of stone masonry joints, in: Struct. Anal. Hist. Constr. Preserv. Saf. Significance - Proc. 6th Int. Conf. Struct. Anal. Hist. Constr. SAHC08, 2008. https://doi.org/10.1201/9781439828229.ch87.

[28] P.B. Lourenço, L.F. Ramos, Characterization of cyclic behavior of dry masonry joints, J. Struct. Eng. (2004). https://doi.org/10.1061/(ASCE)0733-9445(2004)130:5(779).

[29] A.K. Chopra, Dynamics of Structures 4th Edition, 2019. https://doi.org/10.1017/CBO9781107415324.004.

[30] L. Luzi, R. Puglia, E. Russo, M.D. Amico, G. Lanzano, F. Pacor, C. Felicetta, Engineering Strong-Motion database : a gateway to access European strong motion data, 16th World Conf. Earthq. Eng. Santiago, Chile, 9-13 January. 899 (2017).