[EN] A simplified analytical method ("FAST") for the estimation of large-scale vulnerability of Reinforced Concrete (RC) Moment Resisting Frames with masonry infills is proposed and subsequently tested by using real damage scenario caused by the 2011 Lorca earthquake as a benchmark. FAST is a spectral-based approach that allows predicting the average non-structural Damage State expected for each class of building (defined by number of storeys, age of construction, infills ratio in plan and location) for a given demand level. It accounts for non-uniformity of infills in elevation, i.e. a reduction of infills ratio of the ground floor. FAST is based on: (i) the definition of approximated capacity curves of the infilled building, assuming that the RC frame is designed according to the corresponding seismic code; and on (ii) the assumption of "a priori" deformed shapes in accordance with the attainment of each non-structural damage state at 1st storey, estimated through experimental and numerical correlations. Two versions of FAST are proposed: a "simplified" approach aimed at the evaluation of uniformly infilled frames; and a "generalised" version which can account for any intermediate situation between uniformly infilled frames and pilotis frames (i.e. without infills at 1st storey). Also, some extensions of the method are highlighted. Aimed at testing FAST, the real damage scenario after the earthquake of Lorca (2011) is used as a benchmark, despite its impulsivity and directivity. In order to define the specific input parameters for the case study, information regarding ground motion, post-earthquake damage scenario and also building design practice must be collected. Hence, a detailed review of historical Spanish seismic codes and a critical analysis of current Spanish seismic code NCSE-02 in comparison with current reference performance-based codes such as Eurocode 8 are provided. Special emphasis is placed on provisions which can prevent a proper capacity design and that, in turn, can cause brittle failures or favour the interaction with infills. Also, the prescription of lower behaviour factor for wide-beam frames with respect to deep-beam frames -which is not present in most codes¿ is discussed; outcomes of several case studies suggest that such prescription is obsolete. Finally, FAST is applied to Lorca earthquake and predicted damage scenarios are obtained, considering different assumptions for input values. Results show proper agreement between predicted and real damages. Structural collapses were rarely observed, even though the PGA was three times higher than the typical acceleration of design, so FAST proves that masonry infills provided additional strength to RC frames. / [ES] Se propone un método analítico simplificado ("FAST") para la estimación de la vulnerabilidad a gran escala de edificios porticados de hormigón armado con tabiquería de fábrica, posteriormente testeado mediante la adopción del escenario de daño real correspondiente al terremoto de Lorca de 2011 como patrón de comparación. FAST es un procedimiento espectral que permite predecir el nivel de daño no estructural medio esperado para cada clase de edificio (definido por su número de plantas, año de construcción, densidad de tabiquería en planta y localización geográfica), considerando un nivel de demanda dado. El método tiene en cuenta la irregularidad de la tabiquería en alzado, es decir, la posible reducción relativa de tabiquería en planta baja. FAST se basa en: (i) la definición de curvas de capacidad aproximadas para los edificios tabicados, asumiendo que la estructura de HA se ha proyectado según la norma sísmica correspondiente en cada caso; y en (ii) la asunción de deformadas "apriorísticas" coherentes con cada grado de daño (suponiendo que éste se alcanza siempre en planta baja), estimadas a través de correlaciones experimentales y numéricas. Se proponen dos versiones de FAST: una "simplificada" para la evaluación de edificios uniformemente tabicados en altura, y otra "generalizada", que es capaz de tener en cuenta cualquier situación intermedia entre el prototipo uniformemente tabicado y el de planta baja diáfana. Además, se proponen ciertas extensiones al método. A fin de validar FAST, se elige el escenario de daño real correspondiente al terremoto de Lorca (2011) como patrón de comparación, a pesar de su impulsividad y directividad. Para definir los parámetros de input correspondientes al caso de estudio, es necesario recopilar previamente la información concerniente a la señal sísmica, el escenario de daño y las características del parque construido. Por tanto, se lleva a cabo una revisión exhaustiva de las normas sísmicas históricas en España y un análisis crítico de la norma sísmica española actual NCSE-02 en comparación con otras normas actuales de referencia basadas en el desempeño, como el Eurocódigo 8, haciendo énfasis en las provisiones que no garantizan el diseño por capacidad y que por tanto pueden provocar mecanismos frágiles o favorecer la excesiva influencia de la tabiquería. Además, se discute sobre la restricción del coeficiente de ductilidad en estructuras de vigas planas, cuestión que no se refleja en otras normas. Los resultados obtenidos mediante análisis de casos de estudio muestran que dicha prescripción resulta obsoleta para normas actuales. Finalmente, FAST se aplica al caso del terremoto de Lorca, obteniéndose predicciones de daño medio para diferentes asunciones. Los resultados muestran una coincidencia aceptable entre la predicción y los daños reales. FAST confirma que la causa principal de la práctica ausencia de colapsos (ante un terremoto con PGA triple que la típica de proyecto) hay que buscarla en la contribución estructural de la tabiquería de fábrica. / [CA] Es proposa un mètode analític simplificat ("FAST") per a l'estimació de la vulnerabilitat a gran escala d'edificis porticats de formigó armat amb envans de fàbrica. Posteriorment, el mètode ha estat testejat mitjançant l'adopció de l'escenari de dany real corresponent al terratrèmol de Lorca de 2011 com a patró de comparació. FAST és un procediment espectral que permet predir el nivell de dany no estructural mitjà esperat per a cada classe d'edifici (definit pel seu nombre de plantes, any de construcció, densitat d'envans en planta i localització geogràfica), considerant un determinat nivell de demanda. El mètode té en compte la irregularitat de la distribució de envans al llarg de les diferents plantes del edifici. Es a dir, es pot tenir en compte que, freqüentment, hi ha una menor quantitat de d'envans a la planta baixa. FAST es fonamenta en: (i) la definició de corbes de capacitat aproximades que tenen en compte no sols la estructura del edifici sinó també els envans i assumint que l'estructura de HA s'ha projectat segons la norma sísmica corresponent en cada cas; (ii) l'assumpció de deformades "apriorístiques" coherents amb cada grau de dany (suposant que aquest es dona sempre a la planta baixa) que han estat estimades a través de correlacions experimentals i numèriques. Es proposen dues versions de FAST: una "simplificada" per a l'avaluació d'edificis amb envans uniformement repartits per totes les plantes, i una altra "generalitzada", que és capaç de tenir en compte qualsevol situació intermèdia entre el prototip uniformement paredat i el de planta baixa diàfana. A més, es proposen certes extensions al mètode. Per tal de validar FAST, es tria l'escenari de dany real corresponent al terratrèmol de Lorca (2011) com a patró de comparació, malgrat la seva impulsivitat i directivitat. Per definir els paràmetres de entrada corresponents al cas d'estudi, cal recopilar prèviament la informació concernent al senyal sísmica, l'escenari de dany i les característiques del parc construït. Per tant, es porta a terme una revisió exhaustiva de les normes sísmiques històriques a Espanya i una anàlisi crítica de la norma sísmica espanyola actual (NCSE-02) comparant-la amb altres normes actuals de referència, com l'Eurocodi 8, fonamentat en el concepte d'acompliment. També es fa èmfasi a les provisions que no garanteixen el disseny per capacitat i que, per tant, poden provocar mecanismes de col·lapse fràgils o afavorir la interacció de la estructura amb els envans. A més, es discuteix sobre la restricció del coeficient de ductilitat de les estructures de bigues planes ja que es una qüestió que no aborden la majoria de les normes. Els resultats obtinguts mitjançant l'anàlisi de casos d'estudi mostren que aquesta restricció resulta obsoleta a les normes actuals. Finalment, FAST s'aplica al cas del terratrèmol de Lorca, obtenint prediccions de dany mitjà per a diferents combinacions del paràmetres de entrada. Els resultats mostren una coincidència acceptable entre la predicció i els danys reals. FAST confirma que la causa principal de la pràctica absència de col·lapses (davant un terratrèmol amb PGA triple que la típica de projecte) cal buscar-la en la contribució estructural dels envans. / Gómez Martínez, F. (2015). FAST simplified vulnerability approach for seismic assessment of infilled RC MRF buildings and its application to the 2011 Lorca (Spain) earthquake [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/54780 / TESIS / Premios Extraordinarios de tesis doctorales

La escasez de registros sísmicos de gran magnitud considerados significativos, limita la determinación de la respuesta sísmica de una edificación de concreto armado. En este sentido, los acelerogramas artificiales representan una alternativa para definir el evento sísmico porque consideran condiciones específicas del sitio en estudio. Esta investigación analiza la respuesta sísmica de las estructuras para diversos registros sísmicos artificiales generados de espectros de diseño para distintas condiciones geotécnicas. El procedimiento de análisis empleado será el dinámico tiempo historia no lineal para obtener una mayor precisión en la respuesta sísmica. Los resultados obtenidos muestran que las derivas de entrepiso de las señales artificiales creadas con la función de intensidad de Liu se ajustan mejor a las derivas obtenidas del sismo real escalado. / The lack of large seismic records in some world regions limits the determination of the seismic response of a building. For that reason, artificial accelerograms represent an alternative to define the seismic event because they consider specific conditions of study site. This research analyses the structures seismic response for various artificial seismic records generated from design spectra and different geotechnical conditions. Dynamic nonlinear time history analysing was used to obtain greater precision in the seismic response. The results obtained show that the mezzanine drifts of the artificial signals created with the Liu intensity function better fit the drifts obtained from the scaled real earthquake. / Tesis

El presente estudio de investigación evalúa la respuesta sísmica de una clínica con aislamiento símico en Lima bajo la Norma Peruana de Aislamiento Sísmico E.031. Esta será comparada con la norma la Norma Chilena de Diseño Sísmico de Edificios NCh2745 y la Norma Americana ASCE/SEI 7, dichas normas internacionales han sido diseñadas para soportar eventos sísmicos severos, presentando parámetros rigurosos, con los cuales se podrá destacar las fortalezas y debilidades frente a la nueva Norma Peruana. En los capítulos siguientes se da entendimiento a la información que se debe poseer para analizar las tres normas, conceptos básicos de sismología y dinámica estructural, dentro de cada norma se verán los alcances, factores y parámetros que intervienen en la determinación del espectro de diseño, así como el análisis sísmico dinámico que las normas proponen y el modelamiento de la estructura de la clínica en el software ETABS. Luego se comparan los resultados de la respuesta sísmica, desplazamientos laterales, derivas y fuerzas cortantes, en las que se verán las exigencias que cada norma, llegando a saber si nuestra Norma Peruana en su modificación y mejora de su contenido se proyecta a ser una de las mejores normas de diseño sismorresistente, obteniendo así una perspectiva de nuestra Norma Peruana frente a una norma internacional ya consolidada y avalada por los años frente a sismos severos. / This research study evaluates the seismic response of a clinic with simian isolation in Lima under the draft Peruvian Seismic Isolation Standard E.031. This will be compared with the North American standard ASCE SEI 7-16 and the Chilean Seismic Design Standard for Buildings 2745, these international standards have been designed to withstand severe seismic events, presenting rigorous parameters, with which we can highlight the strengths and weaknesses against the new Peruvian Standard. In the following chapters, understanding is given to the information that must be possessed to analyze the three norms, basic concepts of seismology and structural dynamics, within each norm the scope, factors and parameters that are involved in the determination of the design spectrum will be seen, as well as the dynamic seismic analysis that the standards propose and the modeling of the clinical structure in the ETABS software. Then the results of the seismic response, lateral displacements, drifts and shear forces are compared, in which the requirements of each norm will be seen, getting to know if our Peruvian Standard in its modification and improvement of its content is projected to be one of the best seismic resistant design standards, thus obtaining a perspective of our Peruvian Standard against an international standard already consolidated and endorsed by the years against severe earthquakes. / Tesis

The purpose of my master’s thesis is the solution steel hall with concrete columns, that is loaded by an earthquake. This simulation program was used RFEM. To calculate was used the spectral and temporal analysis, and that on models of structures with several combinations of materials. The analysis was performed for both the general direction of the earthquake, so for combinations of directions according to standard procedures in EC8.

博士(心理学) / Doctor of Philosophy in Psychology / 同志社大学 / Doshisha University

A research study has been conducted to simulate liquefaction in saturated sandy soil induced by nearby controlled blasts. The purpose of the study is to help quantify soil characteristics under multiple and consecutive high-magnitude shock environments similar to those produced by large earthquakes. The simulation procedure involved the modeling of a three-dimensional half-space soil region with pre-defined, embedded, and strategically located explosive charges to be detonated at specific time intervals. LS-DYNA, a commercially available finite element hydrocode, was the solver used to simulate the event. A new geo-material model developed under the direction of the U.S. Federal Highway Administration was applied to evaluate the liquefaction potential of saturated sandy soil subjected to sequential blast environments. Additional procedural enhancements were integrated into the analysis process to represent volumetric effects of the saturated soil's transition from solid to liquid during the liquefaction process. Explosive charge detonation and pressure development characteristics were modeled using proven and accepted modeling techniques. As explosive charges were detonated in a pre-defined order, development of pore water pressure, volumetric (compressive) strains, shear strains, and particle accelerations were carefully computed and monitored using custom developed MathCad and C/C++ routines. Results of the study were compared against blast-test data gathered at the Fraser River Delta region of Vancouver, British Columbia in May of 2005 to validate and verify the modeling procedure's ability to simulate and predict blast-induced liquefaction events. Reasonable correlations between predicted and measured data were observed from the study.

For the most recent and correct article, please click here: http://ascelibrary.org/doi/abs/10.1061/9780784412787.086 This study examines the use of performance-based approaches in liquefaction hazard analysis. Two new methods of performance-based liquefaction initiation analysis are proposed which use the works of Juang et al. (2012) and Boulanger and Idriss (2012). Further advances are made by incorporating the performance-based magnitude scaling factors as proposed by Cetin et al. (2012). Using these new equations a comparative study is made between the three methods. Further comparisons are made between the performance-based approaches and the more widely used deterministic approaches. The comparisons reveal that on average for the 11 sites used in this study, the performance-based approaches tend to be slightly less conservative than deterministic approaches overall, with large differences possible for some locations in the country. They also reveal that the newer performance-based approaches are generally less conservative than the approach proposed by Kramer and Mayfield (2007). Some cases where this relationship does not hold true and the new relationships are more conservative are outlined.

[ES] La Constitución del Ecuador establece que el acceso a una vivienda digna es un derecho fundamental. Sin embargo, muchos ciudadanos viven en situaciones de riesgo, ya que las edificaciones que habitan no tienen características físicas y/o estructurales adecuadas. Esto se acentúa en la zona rural, en donde la necesidad de casas que cumplan estándares de calidad es en promedio 71, 2% más que las ciudades. En la mayoría de construcciones que se realizan en Ecuador, se usan materiales convencionales como el hormigón, bloques y ladrillos. Por lo que, cubrir la totalidad del déficit de vivienda (665 612 unidades) requiere una gran inversión económica; además, del alto costo ambiental que representaría; ya que, los materiales mencionados tienen consumos energéticos altos desde su producción hasta su puesta en obra. Es evidente entonces que la dotación de vivienda debe hacerse con materiales sustentables y accesibles a la mayoría de la población. Una alternativa es la paja, que es natural, renovable, sumidero de CO2 y biodegradable. En Ecuador se obtienen anualmente 28 754,492 toneladas de paja de trigo y cebada. Con este desecho de la cosecha, se podrían hacer fardos, con los cuales construir casas. Sin embargo, en el país existe muy poco conocimiento de este material y el sistema constructivo que se requiere para edificar de forma técnica y segura. La presente investigación aborda la caracterización física y mecánica de los fardos producidos localmente para determinar su posibilidad de su uso como material de construcción. Además, se realizaron ensayos pseudo-dinámicos a muros portantes realizados con fardos y recubiertos con dos alternativas de mortero. Con los resultados obtenidos, se realizó la modelación estructural de una vivienda tipo, determinando que el desplazamiento lateral relativo de la misma, cumple los estándares de la Norma Ecuatoriana de la Construcción para edificaciones sismo resistentes. También se realizó un análisis económico, determinando que el costo de la vivienda tipo es inferior al valor establecido para casas de interés social en el país. Lo que determina su accesibilidad al segmento poblacional más pobre. Además, se elaboró un manual, que detalla el procedimiento constructivo de la casa tipo, de forma clara y sencilla para hacerlo de fácil entendimiento. / [CA] La Constitució de l'Equador estableix que l'accés a un habitatge digne és un dret fonamental. No obstant això, molts ciutadans viuen en situacions de risc, ja que les edificacions que habiten no tenen característiques físiques i/o estructurals adequades. Això s'accentua en la zona rural, on la necessitat de cases que complisquen estàndards de qualitat és en mitjana 71,2% més que les ciutats. En la majoria de construccions que es realitzen a l'Equador, s'usen materials convencionals com el formigó, blocs i rajoles. Pel que, cobrir la totalitat del dèficit d'habitatge (665 612 unitats) requereix una gran inversió econòmica; a més, de l'alt cost ambiental que representaria; ja que, els materials esmentats tenen consums energètics alts des de la seua producció fins a la seua posada en obra. És evident llavors que la dotació d'habitatge ha de fer-se amb materials sustentables i accessibles a la majoria de la població. Una alternativa és la palla, que és natural, renovable, embornal de CO2 i biodegradable. A l'Equador s'obtenen anualment 28 754,492 tones de palla de blat i ordi. Amb aquesta deixalla de la collita, es podrien fer fardells, amb els quals construir cases. No obstinate això, al país existed molt poc coneixement d'aquest material I el sistema construction que es required per an edificar de manera tècnica I Segura. La present investigació aborda la caracterització física i mecànica dels fardells produïts localment per a determinar la seua possibilitat del seu ús com a material de construcció. A més, es van realitzar assajos pseudo-dinàmics a murs portants realitzats amb fardells i recoberts amb dues alternatives de morter. Amb els resultats obtinguts, es va realitzar el modelatge estructural d'un habitatge tipus, determinant que el desplaçament lateral relatiu d'aquesta, compleix els estàndards de la Norma Equatoriana de la Construcció per a edificacions sisme resistents. També es va realitzar una anàlisi econòmica, determinant que el cost de l'habitatge tipus és inferior al valor establit per a cases d'interés social al país. El que determina la seua accessibilitat al segment poblacional més pobre. A més, es va elaborar un manual, que detalla el procediment constructiu de la casa tipus, de manera clara i senzilla per a fer-ho de fàcil enteniment. / [EN] The Constitution of Ecuador establishes that access to decent housing is a fundamental right. However, many citizens live in risky situations since their buildings do not have adequate physical and structural characteristics. This is accentuated in rural areas, where the need for houses that meet quality standards is, on average, 71.2% higher than in the cities. In most constructions in Ecuador, conventional materials such as concrete, blocks, and bricks are used. Therefore, covering the entire housing deficit (665 612 units) requires a significant economic investment, in addition to the high environmental cost, since the materials have high energy consumption from production to installation. It is evident then that housing must be built with sustainable materials accessible to most of the population. One alternative is straw, which is natural, renewable, a CO2, and biodegradable. In Ecuador, 28 754.492 tons of wheat and barley straw are obtained annually. With this waste from the harvest, bales could be made with which to build houses. However, there needs to be more knowledge of this material and the construction system required to build technically and safely in the country. The present research addresses the physical and mechanical characterization of locally produced bales to determine the possibility of their use as a construction material. In addition, pseudo-dynamic tests were carried out on load-bearing walls made with bales. An economic analysis was also carried out, determining that the cost of the house type is lower than the value established for houses of social interest in the country. This determines its accessibility to the poorest segment of the population. In addition, a manual was prepared detailing the construction procedure of the house type clearly and straightforwardly to make it easy to understand. / Viera Arroba, LP. (2023). Factibilidad constructiva de viviendas con muros portantes de fardos de paja energéticamente eficientes y sismo resistentes en la zona andina del Ecuador [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/196654

Изучена эффективность применения и рациональность использования гофрированных конструкций для проектирования сейсмостойких стальных рамных каркасов с использованием современных методов сейсмозащиты. / Studied the effectiveness of the use and rationality of the use corrugated structures for the design of earthquake-resistant steel frames using modern methods of seismic protection.

Metamaterials are typically described as materials with ’unusual’ wave propagation properties. Originally developed for electromagnetic waves, these materials have also spread into the field of acoustic wave guiding and cloaking, with the most relevant of these ’unusual’ properties, being the so called band-gap phenomenon. A band-gap signifies a frequency region where elastic waves cannot propagate through the material, which in principle, could be used to protect buildings from earthquakes. Based on this, two relevant concepts have been proposed in the field of seismic engineering, namely: metabarriers, and metamaterial-based foundations. This thesis deals with the development of the Metafoundation, a metamaterial-based foundation system for the seismic protection of fuel storage tanks against excessive base shear and pipeline rupture. Note that storage tanks have proven to be highly sensitive to earthquakes, can trigger sever economic and environmental consequences in case of failure and were therefore chosen as a superstructure for this study. Furthermore, when tanks are protected with traditional base isolation systems, the resulting horizontal displacements, during seismic action, may become excessively large and subsequently damage connected pipelines. A novel system to protect both, tank and pipeline, could significantly augment the overall safety of industrial plants. With the tank as the primary structure of interest in mind, the Metafoundation was conceived as a locally resonant metamaterial with a band gap encompassing the tanks critical eigenfrequency. The initial design comprised a continuous concrete matrix with embedded resonators and rubber inclusions, which was later reinvented to be a column based structure with steel springs for resonator suspension. After investigating the band-gap phenomenon, a parametric study of the system specifications showed that the horizontal stiffness of the overall foundation is crucial to its functionality, while the superstructure turned out to be non-negligible when tuning the resonators. Furthermore, storage tanks are commonly connected to pipeline system, which can be damaged by the interaction between tank and pipeline during seismic events. Due to the complex and nonlinear response of pipeline systems, the coupled tank-pipeline behaviour becomes increasingly difficult to represent through numerical models, which lead to the experimental study of a foundation-tank-pipeline setup. Under the aid of a hybrid simulation, only the pipeline needed to be represented via a physical substructure, while both tank and Metafoundation were modelled as numerical substrucutres and coupled to the pipeline. The results showed that the foundation can effectively reduce the stresses in the tank and, at the same time, limit the displacements imposed on the pipeline. Leading up on this, an optimization algorithm was developed in the frequency domain, under the consideration of superstructure and ground motion spectrum. The advantages of optimizing in the frequency domain were on the one hand the reduction of computational effort, and on the other hand the consideration of the stochastic nature of the earthquake. Based on this, two different performance indices, investigating interstory drifts and energy dissipation, revealed that neither superstructure nor ground motion can be disregarded when designing a metamaterial-based foundation. Moreover, a 4 m tall optimized foundation, designed to remain elastic when verified with a response spectrum analysis at a return period of 2475 years (according to NTC 2018), reduced the tanks base shear on average by 30%. These results indicated that the foundation was feasible and functional in terms of construction practices and dynamic response, yet unpractical from an economic point of view. In order to tackle the issue of reducing the uneconomic system size, a negative stiffness mechanism was invented and implemented into the foundation as a periodic structure. This mechanism, based on a local instability, amplified the metamaterial like properties and thereby enhanced the overall system performance. Note that due to the considered instability, the device exerted a nonlinear force-displacement relationship, which had the interesting effect of reducing the band-gap instead of increasing it. Furthermore, time history analyses demonstrated that with 50% of the maximum admissible negative stiffness, the foundation could be reduced to 1/3 of its original size, while maintaining its performance. Last but not least, a study on wire ropes as resonator suspension was conducted. Their nonlinear behaviour was approximated with the Bouc Wen model, subsequently linearized by means of stochastic techniques and finally optimized with the algorithm developed earlier. The conclusion was that wire ropes could be used as a more realistic suspension mechanism, while maintaining the high damping values required by the optimized foundation layouts. In sum, a metamaterial-based foundation system is developed and studied herein, with the main findings being: (i) a structure of this type is feasible under common construction practices; (ii) the shear stiffness of the system has a fundamental impact on its functionality; (iii) the superstructure cannot be neglected when studying metamaterial-based foundations; (iv) the complete coupled system can be tuned with an optimization algorithm based on calculations in the frequency domain; (v) an experimental study suggests that the system could be advantageous to connected pipelines; (vi) wire ropes may serve as resonator suspension; and (vii) a novel negative stiffness mechanism can effectively improve the system performance.