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Nonlinear numerical assessment of the seismic response of hillside RC buildings

Earthquake Engineering and Engineering Vibration 2021年第2期20卷 423-440页

作者： Miguel A.Gómez Edgar Giovanny Díaz-Segura juan carlos vielma Civil Engineering School Pontificia Universidad Católica de ValparaísoValparaíso 2340000Chile

Major damage has been reported in hilly areas after major earthquakes,primarily because of two special conditions:the variation in the seismic ground motion due to the inclined ground surface and the irregularities caused by a stepped base level in the *** aim of this study is to evaluate possible differences in the responses of Chilean hillside buildings through numerical linear-elastic and nonlinear *** the first step,a set of response-spectrum analyses were performed on four simplified 2D structures with mean base inclination angles of 0°,15°,30°,and 45°.The structures were designed to comply with Chilean seismic codes and standards,and the primary response parameters were *** assess the seismic performance of the buildings,nonlinear static(pushover)and dynamic(time-history)analyses were performed with SeismoStruct *** analyses were used to compare the nonlinear response at the maximum roof displacement and the damage ***-history analyses were performed to assess the nonlinear dynamic response of the structures subjected to seismic ground motions modified by topographic *** consider the topographic modification,acceleration records were obtained from numerical models of soil,which were calculated using the rock acceleration record of the Mw 8.01985 Chilean *** differences in the structure responses(roof displacements and maximum element forces and moments)were caused by the topographic effects in the seismic input motion,with the highly predominant ones being the differences caused by the step-back configuration at the base of the *** concentrations of shear forces in short walls were observed,corresponding to the walls located in the upper zone of the foundation *** response of the structures with higher angles was observed to be more prone to fragile failures due to the accumulation of shear *** though hillside buildings gain stiffness in the lower stories,resulting

关键词： topographic effect hillside buildings nonlinear analyses shear-wall buildings

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Seismic Safety of RC Framed Buildings Designed According to Modern Codes

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Journal of Civil Engineering and Architecture 2011年第7期5卷 567-575页

作者： juan carlos vielma Barbat Alex Oiler Sergio Department of Structural Engineering Lisandro A lvarado University Barquisimeto Venezuela Depertment of Strength of Materials Technical University of Catalonia Barcelona Spain

In order to ensure that a structure does not collapse when subjected to the action of strong ground motions, modern codes include prescriptions in order to guarantee the ductile behavior of the elements and of the whole structure. Obviously, it would be of special importance for the designer to know during the design process the extent of damage that the structure will suffer under the seismic action specified by the design spectrum and also the probability of occurrence of different states of behavior. The incremental nonlinear static analysis procedure used in this paper allows formulating a new, simplified, seismic damage index and damage thresholds associated with five limit states. The seismic behavior of a set of regular reinforced concrete buildings designed according to the EC-2/EC-8 prescriptions for a high seismic hazard level is then studied using the proposed damage index and damage states. Fragility curves and damage probability matrices corresponding to the performance point are calculated for the studied buildings. The obtained results show that the collapse damage state is not reached in the buildings designed according to the prescriptions of EC-2/EC-8 and also that the damage does not exceed the irreparable damage limit state.

关键词： Non linear analysis limit states overstrength ductility redundancy.

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Seismic response of high-rise steel framed buildings with Chevron-braced designed according to Venezuelan codes

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Natural Science 2012年第8期4卷 694-698页

作者： Ronald Ugel juan carlos vielma Reyes Herrera Sigrit Perez Alex Barbat Senior Technical School of Roads Canals and Ports Engineers of Barcelona Technical University of Catalonia. Barcelona Spain Structural Engineering Department School of Civil Engineering Lisandro Alvarado University. Barquisimeto Venezuela

The object of this study is to determine the seismic response of regular high-rise steel buildings with chevron-braced frames. Mechanics models of three buildings of 14, 18 and 20 stories are studied, all of them with similar geometric characteristics in plant and elevation. These models are realized using prescriptions and parameters from venezuelan design codes. The seismic action is carry on through varius synthetic design spectrum compatible accelerograms defined by the seismic codes in this study, with three levels of intensity corresponding to three specific Limit States. Dynamic analysis is used to compute parameters of ductility, over strength and maximum displacements. From these results it can be concluded that chevron-braced frames presented a good overall performance and non V-braced frames show greater damage due to dynamic actions, validating non linear dynamic analysis as a very powerful tool to seismic-resistance design and chevron-braced frames as a very useful choice in improving the response of tall steel structures. since this lateral bracing system is absent from Venezuelan seismic codes.

关键词： Framed Steel Buildings Chevron Braced Frames Non Linear Analysis Over Strength Seismic Response

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Optimal design and earthquake-resistant design evaluation of low-rise framed RC structure

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Natural Science 2012年第8期4卷 677-685页

作者： Reyes Indira Herrera juan carlos vielma Ronald Ugel Yolsanie Martínez Alex Barbat Senior Technical School of Roads Canals and Ports Engineers of Barcelona Technical University of Catalonia Barcelona Spain Structural Engineering Department School of Civil Engineering Lisandro Alvarado University Venezuela

This study evaluates the seismic response of an existing two stories RC building using non-linear analysis. The original model was resized and there were obtained two buildings designed under two different methodologies to fulfill the Venezuelan codes requirements for a high seismic hazard. An elastic analysis was applied to the original building in order to verify interstory drifts;the resizing building it was designed under requirements of strong column-wake beam condition. A third building was modeled according to the seismic displacement design procedure. It were performed non-linear static analysis and 2D and 3D dynamic analyses, obtaining capacity curves, structural ductility, structural performance point, global and interstory drifts for each building. Torsional effects for the resizing building were also computed from 3D analysis. In the original building it was obtained a weak seismic behavior, while resized buildings presented good seismic performance under the Limits States evaluated in this study.

关键词： Resized Building Linear Analysis Nonlinear Analysis Seismic Response Torsional Effects

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Biodegradable Additive for the Construction Industry

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Journal of Renewable Materials 2019年第6期7卷 523-525页

作者： juan carlos Torres Lozada AIBRIM San SebastiánGuipúzcoa Spain

This paper presents the patent of a new additive for the construction industry,which is obtained from the biomass residues of the wood *** additive is biodegradable and has fluidifying,foaming,plasticizing and stabilizing *** the additive is mixed with cement binder compositions,cement mortar and concrete,lightweight,flame-retardant cellular materials,thermal and acoustic insulators are obtained.

关键词： Wood biomass waste additives construction

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Transmission line protection challenges influenced by inverter-based resources:a review

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Protection and Control of Modern Power Systems 2022年第1期7卷 406-422页

作者： juan carlos Quispe Eduardo Orduña Institute of Electrical and Energy-CONICET Universidad Nacional de San JuanSan JuanArgentina Universidad Tecnológica del Perú LimaPeru

High penetration of renewable energy sources(RES)leads to new challenges for protection *** schemes are typically designed according to the dynamic behavior of rotating machines as generation sources,while the RES dynamic response,mainly governed by inverters,is not ***,some relevant algorithms of transmission line protection are experiencing challenges because of the fact that magnitude and phase angle com-parison,amount of negative-sequence,and short-circuit current level are affected by the ***,an in-depth study of this issue is necessary,one which considers the main causes and new methodological criteria *** work presents an extensive literature review of the evaluation of electrical protection performance and the effects of RES connected to a power grid through *** data on many representative publications related to this topic are obtained to show the current research lines and their proposed *** addition,this work identi-fies the main protection functions affected and describes the new protection schemes that consider ***,an analysis and discussion of the selected bibliography are presented.

关键词： Inverter-based resources Inverter control system Photovoltaic plant Transmission line protection Wind farm

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A Note on Extreme Points in Dual Spaces

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Acta Mathematica Sinica,English Series 2013年第3期29卷 471-476页

作者： juan Francisco MENA-JURADO juan carlos NAVARRO-PASCUAL Departamento de Análisis Matemático Facultad de Ciencias Universidad de Granada Departamento de lgebra y Análisis Matemático Universidad de Almería

Given a normed space X it can be easily proven that every extreme point in Bx＊, the unit ball of X＊, is the restriction of an extreme point in Bx Our purpose is to study when the restrictions of extreme points in B... 详细信息

关键词： Extreme point Ll-predual M-ideal

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The effects of patch richness on con-specific interference in the parasitoid Ibalia leucospoides （Hymenoptera： Ibaliidae）

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Insect Science 2010年第4期17卷 379-385页

作者： Valeria Fernandez-Arhex juan carlos Corley Lab. Ecologia de tnsectos INTA EEA-Bariloche Bariloche Rio Negro Argentina

We experimentally studied con-specific interference in Ibalia leucospoides, a parasitoid of the woodwasp Sirex noctilio, on pine logs containing variable numbers of woodwasp larvae. Competiton occurred when two different-sized female parasitoids foraged on a host patch, and consequently the small female always abandoned the patch. Regardless of host density, con-specific presence did not affect the attack rate, the number of hosts attacked, nor patch residence time by the winner, when compared to a control female that foraged alone. In contrast, con-specific presence reduced patch time and the number of hosts attacked by the loser. Finally patch time （by both） as well as number of hosts attacked （by the winner only） increased with host density per patch. Our results suggest that con-specific presence has different consequences for different-sized females during patch exploitation.

关键词： aggregation direct competition host-parasitoid interactions parasitoid com-petition patch quality Sirex noctilio

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An unsupervised pattern recognition methodology based on factor analysis and a genetic-DBSCAN algorithm to infer operational conditions from strain measurements in structural applications

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Chinese Journal of Aeronautics 2021年第2期34卷 165-181页

作者： juan carlos PERAFAN-LOPEZ Julian SIERRA-PEREZ Grupo de Investigacion en Ingenieria Aeroespacial Universidad Pontificia BolivarianaCircular 170-01Medellin 050031Colombia

Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) *** methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%.

关键词： Clustering DBSCAN Factor analysis FBGs Pattern recognition Strain field

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Assessment of effectiveness of oral supplementation of isolated fiber of carrot on metabolic parameters in mature rats

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Food Science and Human Wellness 2023年第6期12卷 2022-2028页

作者： Maria Rosana Ramirez Debora Manuale juan carlos Yori Instituto Universitario de Ciencias de la Salud Fundación BarcelóCONICETCenteno 710CP 3340Santo TomeCorrientesArgentina Consejo Nacional de Investigaciones Científi cas Técnicas(CONICET) Buenos Aires C1033AAJArgentina Instituto de Investigaciones en Catálisis y Petroquímica(INCAPE)FIQ-UNL-CONICET Parque Tecnológico Litoral Centro 3000Santa FeArgentina Facultad de Ingeniería Química Universidad nacional del Litoral 3000Santa FeArgentina

This present study was conducted to evaluate the metabolic effects of isolated fi ber of carrot supplementation in *** properties of fi ber were *** groups were as follows:animals fed a standard diet,control group;high fi ber supplementation(70 mg);low fi ber supplementation(35 mg);for 12 *** samples were collected at the time of sacrifi *** weights of heart,liver,kidneys and spleen of the experimental rats with respect to body weight were *** kits were used to determine serum glucose concentration,lipid profi le(cholesterol,HDL-cholesterol,triglycerides),and the two main aminotransferases glutamic-oxalacetic transaminase(GOT)/glutamate-pyruvate transaminase(GPT).A histopathological assay was performed on the heart,liver,and spleen tissues of *** with fi ber favors weight loss in female((242.03±23.73)-(197.81±10.45)g);and male rats((262.50±32.21)-(213.96±12.56)g and induces a decrease in glucose levels in the supplemented *** the exception of total high-density lipoprotein cholesterol,the other lipid fractions decrease signifi cantly in rats *** supplementation did not induce changes in the dissected organs of the supplemented *** conclusion supplementation of fiber,improves glucose control,lower plasma lipid concentrations and reduced body weight in normal rats.

关键词： Carrot fiber Oral supplementation Animal studies

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