Hazard-consistent response spectra in the Region of Murcia (Southeast Spain): comparison to earthquake-resistant provisions

Hazard-consistent ground-motion characterisations of three representative sites located in the Region of Murcia (southeast Spain) are presented. This is the area where the last three damaging events in Spain occurred and there is a significant amount of data for comparing them with seismic hazard estimates and earthquake-resistant provisions. Results of a probabilistic seismic hazard analysis are used to derive uniform hazard spectra (UHS) for the 475-year return period, on rock and soil conditions. Hazard deaggregation shows that the largest hazard contributions are due to small, local events for short-period target motions and to moderate, more distant events for long-period target motions. For each target motion and site considered, the associated specific response spectra (SRS) are obtained. It is shown that the combination of two SRS, for short- and long-period ground motions respectively, provides a good approximation to the UHS at each site. The UHS are compared to design response spectra contained in current Spanish and European seismic codes for the 475-year return period. For the three sites analysed, only the Eurocode 8 (EC8) type 2 spectrum captures the basic shape of the UHS (and not the EC8 type 1, as could be expected a priori). An alternative response spectrum, anchored at short- and long-period accelerations, is tested, providing a close match to the UHS spectra at the three sites. Results underline the important contribution of the frequent, low-to-moderate earthquakes that characterize the seismicity of this area to seismic hazard (at the 475-year return period)

Tsunami hazards in the Catalan Coast, a low-intensity seismic activity area

The final publication is available at Springer via http://dx.doi.org/10.1007/s11069-017-2918-zThe potential impacts of tsunamis along the Catalan Coast (NW Mediterranean) are analysed using numerical modelling. The region is characterized by moderate to low seismic activity and by moderate- to low-magnitude earthquakes. However, the occurrence of historical strong earthquakes and the location of several active offshore faults in front of the coast suggest that the possibility of an earthquake-triggered tsunami is not negligible although of low probability. Up to five faults have been identified to generate tsunamis, being the highest associated possible seismic magnitudes of up to 7.6. Coastal flooding and port agitation are characterized using the Worst-case Credible Tsunami Scenario Analysis approach. The results show a multiple fault source contribution to tsunami hazard. The shelf dimensions and the existence of submerged canyons control the tsunami propagation. In wide shelves, waves travelling offshore may become trapped by refraction causing the wave energy to reach the coastline at some distance from the origin. The free surface water elevation increases at the head of the canyons due to the sharp depth gradients. The effects of potential tsunamis would be very harmful in low-lying coastal stretches, such as deltas, with a high population concentration, assets and infrastructures. The Ebro delta appears to be the most exposed coast, and about the 20% of the delta surface is prone to flooding due to its extremely low-lying nature. The activity at Barcelona port will be severely affected by inflow backflow current at the entrance of up to 2 m/s.Peer ReviewedPostprint (author's final draft

Seismic performance of masonry residential buildings in Lorca's city centre, after the 11th May 2011 earthquake

[EN] Lorca May 11, 2011 earthquake, whose magnitude and intensity reached Mw=5.1 and I=VII, caused heavy damages, showing the vulnerability of masonry historic buildings and reinforced concrete improper designed structures. The main objectives of this paper are to study the seismic response of unreinforced masonry residential building stock in Lorca historic centre and to compare it with the vulnerability and feasible collapse mechanisms predicted by the FaMIVE Method (D Ayala and Speranza in Proceedings of 12th European conference of earthquake engineering. Elsevier Science Limited, London, 2002; Earthq Spectra 19(3):479 509, 2003), which has been proved to be accurate in the description and prediction of damages in this type of structures. For this purpose, three onsite surveys were carried out, in May, June and December 2011, on a sample of the masonry residential buildings in Lorca historic centre (area included in the Special Protection and Rehabilitation Plan of the Historic and Artistic Site of Lorca). Information regarding geometry, quality of materials, structure and c nstruction characteristics was collected, establishing the observed collapse mechanisms and evaluating rigorously damage and crack patterns. Google Street View was used for the analysis of the state of the buildings before the earthquake. These buildings were then assessed and mapped using a GIS system. Results provided good accordance with the observed data, showing, at the same time, very different building seismic performance. Effective connections between façades and party walls, a good maintenance level of masonry and roofs and the use of specific reinforcement elements have proved to be relevant factors in lowering the vulnerability and improving the seismic behaviour of unreinforced masonry structures in Lorca historic centre.Basset Salom, L.; Guardiola Villora, AP. (2014). Seismic performance of masonry residential buildings in Lorca's city centre, after the 11th May 2011 earthquake. Bulletin of Earthquake Engineering. 12(5):2027-2048. doi:10.1007/s10518-013-9559-8S20272048125Basset-Salom L, Guardiola-Víllora A (2013) Influence of the maintenance in seismic response of Lorca historic centre masonry residential buildings after 11 May Earthquake. Studies, Repairs and Maintenance of Heritage Architecture XIII. WIT Trans Built Environ 131:343–354. http://library.witpress.comBenito B, Murphy P, Tsige M, Martínez-Díaz JJ, Gaspar-Escribano JM, García-Mayordomo J, Jiménez ME, García MJ, Canora C, Álvarez-Gómez JA, García-Flores I (2006) Riesgo Sísmico de la Comunidad Autónoma de la Región de Murcia (Proyecto RISMUR). Volumen 6: Informe final. Instituto Geográfico Nacional y Dirección General de Protección Civil Región de MurciaBenito B, Rivas-Medina A, Gaspar-Escribano JM, Murphy P (2012) El terremoto de Lorca (2011) en el contexto de la peligrosidad y el riesgo sísmico en Murcia. Física de la Tierra 24:255–287Buforn E, Benito B, Sanz de Galdeano C, del Fresno C, Muñoz D, Rodríguez I (2005) Study of the damaging earthquakes of 1911, 1999 and 2002 in risk implications. Bull. Seismol. Soc. Am. 95:549–567Cabañas L, Carreño E, Izquierdo A, Martínez JM, Capote R, Martínez J, Benito B, Gaspar J, Rivas A, García J, Pérez R, Rodríguez MA, Murphy P (2011) Informe del sismo de Lorca del 11 de mayo de 2011. IGN, UCM, UPM, IGME, AEIS. http://www.ign.es/ign/resources/sismologia/www/lorca/Lorcainfo2011.pdf . Accessed 15 Dec 2011Catalogue of Protected Buildings (1994) Departamento de Urbanismo de Lorca. http://www.urbanismo.lorca.es/generar/cgi-bin/mapserv.exe . Accessed 15 Dec 2011Carocci CF, Lagomarsino S (2009) Gli edifici in muratura nei centri storici dell’ Aquilano. Progettazione Sismica no 3, pp 117–134D’Ayala DF (2003) Seismic vulnerability and strengthening of historic building, in Fener and Balat Districts, Istanbul EU-Fatih Municipality Programme: Rehabilitation of Fener and Balat Districts DELTUR/MEDTQ/53-02 [PDF]. http://www.fenerbalat.org/admin/files/250_DDayalaReport.pdf . Accessed 13 Jan 2012D’Ayala DF (2005) Force and displacement based vulnerability assessment for traditional buildings. Bull Earthq Eng 3(3):235–265D’Ayala DF (2006) Proceedings of the getty seismic Adobe Project 2006 colloquium seismic vulnerability and conservation strategies for Lalitpur minor, Heritage, pp 120–134D’Ayala DF, Ansal A (2009) Non-linear push over assessment of historic buildings in Istanbul to define vulnerability functions. In: WCCE-ECCE-TCCE joint conference: earthquake and Tsunami, Istanbul, Turkey, p 128D’Ayala DF, Novelli V (2011) Inspection form for the survey of historic buildings, Instructor Manual (WP6. Models for the seismic Vulnerability assessment at territorial scale). EU-FP7 (2010–2012). Performance based approach to the earthquake protection of cultural heritage in European and Mediterranean countries (PERPETUATE). www.perpetuate.euD’Ayala DF, Paganoni S (2011) Assessment and analysis of damage in L’Aquila historic city centre after 6th April 2009. Bull Earthq Eng 9:81–104D’Ayala DF, Speranza E (2002) An integrated procedure for the assessment of seismic vulnerability of historic buildings. In: Proceedings of 12th European conference of earthquake engineering, Paper Reference 561. Elsevier Science Limited, LondonD’Ayala DF, Speranza E (2003) Definition of collapse mechanisms and seismic vulnerability of historic masonry buildings. Earthq Spectra 19(3):479–509Gaspar-Escribano JM, Benito B (2007) Ground motion characterization of low-to-moderate seismicity zones and implications for seismic design: lessons from recent, Mw $$\sim$$ ∼ 4.8, damaging earthquakes in Southeast Spain. Bull Seismol Soc Am 97:531–544Gaspar-Escribano JM, Murphy P, Benito B (2005) Study of ground motions and damage trends in different building types caused by recent low-magnitude earthquakes in SE Spain. Lessons for defining seismic design criteria. In: Proceedings 250th anniversary of the 1755 Lisbon earthquake, Lisbon, 1–4 November 2005Gaspar-Escribano JM, Benito B, García-Mayordomo J (2008) Hazard-consistent response spectra in the Region of Murcia (Southeast Spain): comparison to earthquake-resistant provisions. Bull Earthq Eng 6:179–196Goula X, Irizarry J, Figueras S, Macau A, Barbat A, Carreño LM, Lantada N, Valcarcel J (2011) El terremoto de Lorca del 11 de Mayo de 2011. Informe de la inspección y de los trabajos de campo realizados, Monografies técniques, Barcelona, IGCGrünthal G (1998) European Macroseismic Scale 1998. In: Cahiers du Centre Européen de Géodynamique et de Séismologie, Luxembourg, 99pGuardiola-Víllora A, Basset-Salom L (2012) Risk of protecting residential buildings in seismic historic centres. Lorca (Spain) Experience after 11th May 2011 Earthquake. In: Proceedings of the ICOMOS ICORP international symposium on cultural heritage protection in times of risk: challenges and opportunities, Istambul. Yildiz Technical University PressIGN (2011) Instituto Geográfico Nacional. Ministerio de Fomento. Serie terremoto NE Lorca (Murcia). 11 de mayo 2011. www.fomento.gob.es/NR/rdonlyres/4196D838-3EB6.../Lorca.pdf . Accessed 15 Dec 2011IGN (2012) Instituto Geográfico Nacional. Ministerio de Fomento. http://www.fomento.gob.es/mfom/lang_castellano/direcciones_generales/instituto_geografico/geofisica/sismologia/ . Accessed 15 Dec 2011Lorca’s City Council (2000) (Ayuntamiento de Lorca). Plan Especial de protección y rehabilitación integral en el conjunto histórico artístico de Lorca (PEPRI. Departamento de Urbanismo de Lorca. http://www.urbanismo.lorca.es/PEPRI.asp . Accessed 15 Dec 2011Lorca’s City Council (2011) (Ayuntamiento de Lorca). Visor geográfico seísmo de Lorca. http://www.lorca.es/ficheros/file/sitLorcaSeismo/index.asp . Accessed 10 June 2011Martínez-Solares JM, Mezcua-Rodriguez J (2002) Catálogo sísmico de la Península Ibérica (880 a.C.-1900). Monografías no 18. Instituto Geográfico Nacional. Madrid. www.ign.es/ign/resources/sismologia/.../Catalogohasta1900.pdf . Accessed 21 Oct 2012Muñoz-Clares M, Fernandez-Carrascosa M, Alcolea-López MO, Arcas-Navarro MC, Arcas-Ruiz N, Caro-del-Vas P, Cruz-López MT, Garcia-Poveda M, Garcia-Valera MA, Llamas-Martinez B, Ruiz-Llanes AE (2012) Sismicidad histórica y documentación municipal: el caso de Lorca. Boletín Geológico y Minero 123(4):415–429Murphy P (1999) Earthquake in the River Mula region, February 2 1999. Study of damage to buildings. Física de la Tierra 11:253–267Murphy P (2006) La Vulnerabilidad de la Edificación de la Región de Murcia, en Riesgo Sísmico de la Comunidad Autónoma de la Región de Murcia (Proyecto RISMUR). Volumen 3: Vulnerabilidad sísmica. Instituto Geográfico Nacional y Dirección General de Protección Civil Región de Murci