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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.

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

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

A Neuro-Fuzzy System for the Post-Earthquake Damage Assessment of Buildings

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A Neuro-Fuzzy System for the Post-Earthquake Damage Assessme...

Standardized Evaluation of Camera-based Driver State Monitoring Systems

The Sixth World Congress on Computational Mechanics in Conjunction with the Second Asian-Pacific Congress on Computational Mechanics

作者： Martha L.Carreno Omar D.Cardona alex H.barbat Department of Structural Mechanics Technical University of Catalonia Jordi Girona 1 -3 Modulo C1 Barcelona 08034 Spain Department of Civil Engineering University of Los Andes 092858 Bogota D.C. Colombia Department of Structural Mechanics Technical University of Catalonia Jordi Girona 1 -3 Modulo C1 Barcelona 08034 Spain

After a strong earthquake the state of the affected buildings should be assessed in order to define their habitability and reparability. Due to the extension of damage in the str uck area, it is not possible to make the evaluations of all the building only by expert engineers. Many inspectors without expertise and knowledge must be involved due to the need of massive survey and the necessity to have the diagnosis as soon as possible to aid the people affected. As a consequence, it is common the tendency of non-expert inspectors to aggravate or to underestimate the real level of damage. This paper develops the algorithmic basis of an integrated tool of computational intelligence tech nique to assist non-experts in the quick building damage diagnosis and occupancy decision -making. A hybrid neuro-fuzzy system is proposed, based on a special three -layer feed-forward artificial neural network and fuzzy rule bases [1-2]. The inputs of the system are fuzzy sets, taking into account that the damage levels of the structural components are linguistic defined by means of qualifications such as light, minor, moderate, average, severe, etc., which are very appropriate to handle subjective and incomplete information. A Kohonen unsupervised learning algorithm is used, as a first module, to assess the structural damage degree. The weights for each appraisal are obtained by the T -conorm of the triangular membership functions, which represent the input d amage level qualifications, and by fitting to a sigmoidal damage function of reference. For the training of the artificial neural network, damage evaluations made after the Quindio's earthquake in Colombia (1999) were used. A fuzzy rule bases module is then used for the habitability and reparability decision -making. It takes into account: 1) the building safety, obtained from the damage evaluation in structural and architectural components, 2) the site seismic effects and 3) the pre -existing conditions that can make the building

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 716-732页

作者： Renran Tian Keyu Ruan Lingxi Li Jialiang Le Jeff Greenberg Saeed barbat IEEE the Transportation Active Safety Institute (TASI) and also with the Department of Computer Information and Graphics TechnologyPurdue School of Engineering and Technology Indiana University-Purdue University Indianapolis (IUPUI) the Transportation Active Safety Institute(TASI) and also with the Department of Electrical and Computer EngineeringPurdue School of Engineering and Technology Indiana University-Purdue University Indianapolis (IUPUI) the Ford Research and Innovation Center

Driver state sensing technologies, such as vehicular systems, start to be widely considered by automotive manufacturers. To reduce the cost and minimize the intrusiveness towards driving, the majority of these systems rely on the in-cabin camera(s) and other optical sensors. With their great capabilities in detecting and intervening of driver distraction and inattention,these technologies may become key components in future vehicle safety and control systems. However, to the best of our knowledge,currently, there is no common standard available to objectively compare the performance of these technologies. Thus, it is imperative to develop one standardized process for evaluation *** this paper, we propose one systematic and standardized evaluation process after successfully addressing three difficulties:1) defining and selecting the important influential individual and environmental factors, 2) countering the effects of individual differences and randomness in driver behaviors, and 3) building a reliable in-vehicle driver head motion tracking tool to collect ground-truth motion data. We have collected data on a large scale on a commercial driver state-sensing platform. For each subject, 30 to 40 minutes of head motion data was collected and included variables, such as lighting conditions, head/face features,and camera locations. The collected data was analyzed based on a proposed performance measure. The results show that the developed process can efficiently evaluate an individual camerabased driver state sensing product, which builds a common base for comparing the performance of different systems.

关键词： Data analysis data collection driver state sensing human factors performance evaluation

Fatality in Kikuchi-Fujimoto disease: A rare phenomenon

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World Journal of Clinical Cases 2017年第2期5卷 35-39页

作者： Bianca barbat Ruby Jhaj Daniyeh Khurram Providence-Providence Park Hospital

Kikuchi-Fujimoto disease(KFD), also known as histiocytic necrotizing lymphadenitis, is an uncommon condition, typically characterized by lymphadenopathy and fevers. It usually has a benign course; however, it may progress to fatality in extremely rare occasions. The diagnosis is made via lymph node biopsy and histopathology. Our patient was a young female who presented with shortness of breath, fever, and malaise. Physical examination revealed significant cervical and axillary lymphadenopathy. Chest X-ray displayed multilobar pneumonia. She required intubation and mechanical ventilation for progressive respiratory distress. Histopathology of lymph nodes demonstrated variable involvement of patchy areas of necrosis within the paracortex composed of karyorrhectic debris with abundant histiocytes consistent with KFD. After initial stabilization, the patient's condition quickly deteriorated with acute anemia, thrombocytopenia and elevated prothrombin time, partial prothrombin time, and D-dimer levels. Disseminated intravascular coagulopathy(DIC) ensued resulting in the patient's fatality. DIC in KFD is not well understood, but it is an important cause of mortality in patients with aggressive disease.

关键词： Kikuchi-Fujimoto disease Disseminated intravascular coagulopathy Histiocytic necrotizing lymphadenitis Lymphadenopathy Fatality

Machine-learning-based head impact subtyping based on the spectral densities of the measurable head kinematics

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Journal of Sport and Health Science 2023年第5期12卷 619-629,F0003页

作者： Xianghao Zhan Yiheng Li Yuzhe Liu Nicholas J.Cecchi Samuel J.Raymond Zhou Zhou Hossein Vahid Alizadeh Jesse Ruan Saeed barbat Stephen Tiernan Olivier Gevaert Michael M.Zeineh Gerald A.Grant David B.Camarillo Department of Bioengineering Stanford UniversityStanfordCA 94305USA Department of Biomedical Data Science Stanford UniversityStanfordCA 94305USA Ford Motor Company 3001 Miller RdDearbornMI 48120USA Technological University Dublin DublinD07 EWV4Ireland Department of Radiology Stanford UniversityStanfordCA 94305USA Department of Neurosurgery Stanford UniversityStanfordCA 94305USA

Background:Traumatic brain injury can be caused by head impacts,but many brain injury risk estimation models are not equally accurate across the variety of impacts that patients may undergo,and the characteristics of different types of impacts are not well *** investigated the spectral characteristics of different head impact types with kinematics ***:Data were analyzed from 3262 head impacts from lab reconstruction,American football,mixed martial arts,and publicly available car crash data.A random forest classifier with spectral densities of linear acceleration and angular velocity was built to classify head impact types(e.g.,football,car crash,mixed martial arts).To test the classifier robustness,another 271 lab-reconstructed impacts were obtained from 5 other instrumented ***,with the classifier,type-specific,nearest-neighbor regression models were built for brain ***:The classifier reached a median accuracy of 96% over 1000 random partitions of training and test *** most important features in the classification included both low-and high-frequency features,both linear acceleration features and angular velocity *** head impact types had different distributions of spectral densities in low-and high-frequency ranges(e.g.,the spectral densities of mixed martial arts impacts were higher in the high-frequency range than in the low-frequency range).The type-specific regression showed a generally higher R2value than baseline models without ***:The machine-learning-based classifier enables a better understanding of the impact kinematics spectral density in different sports,and it can be applied to evaluate the quality of impact-simulation systems and on-field data augmentation.

关键词： Classification Contact sports Head impacts Impact kinematics Traumatic brain injuryTagedAPTARAEnd

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能源转型中的融资问题值得广泛关注

中国银行业 2017年第8期 10-12页

作者： Marie-Anne barbat-Layani 罗倩倩法国银行业联合会

数月来,法国银行业联合会（FBF）一直在努力寻求一条支持能源转型融资的合适且审慎的途径,并且希望各个国际组织团结协作,共同致力于此项课题。气候变化和能源转型是当代最值得关注的两个问题。同时,我们肩负着为后代留下赖以生存的环... 详细信息

数月来,法国银行业联合会（FBF）一直在努力寻求一条支持能源转型融资的合适且审慎的途径,并且希望各个国际组织团结协作,共同致力于此项课题。气候变化和能源转型是当代最值得关注的两个问题。同时,我们肩负着为后代留下赖以生存的环境和欣欣向荣世界的重要责任。如今,人们日益认识到这份责任的重要性。迄今为止,包括法国在内,全球各国都采取了诸多可圈可点的措施。

关键词：融资问题转型能源团结协作国际组织气候变化联合会银行业

Rice and Barnyardgrass:Water Stress and Initial Establishment

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American Journal of Plant Sciences 2017年第12期8卷 3110-3119页

作者： Jose Maria barbat Parfitt Andre Andres Germani Concenco Gustavo Mack Telo Fábio Schreiber Jaqueline Trombetta da Silva Ivana Santos Moisinho Pamela Andrades Timm Sustainable Crop Management Crop ManagementEmbrapa Clima TemperadoPelotasBrazil Federal University of Pelotas(UFPel) PelotasBrazil Federal University of Pelotas(UFPel)and Sustainable Crop Management Embrapa Clima TemperadoPelotasBrazil

The present work aimed to evaluate the effect of different water stress levels on the development of both rice and barnyardgrass. The study was established into greenhouse, in completely randomized design, in factorial scheme 2 × 5, with four replications. Factor “A” comprised the plant species (rice cv. BRS Querência, or the weed Echinochloa crusgalli), and factor “B” comprised the water stress levels: (T1) continuous flood (CF);(T2) 0 kPa (saturated soil);(T3) 10 kPa;(T4) 40 kPa;and (T5) 100 kPa. Plant emergence was assessed every day;plant length was measured 30 days after planting. At the end of the experiment, the number of leaves per plant, root length and shoot and root dry mass were determined. Our data supply evidence that under moderate water stress, up to approximately 40 kPa, rice tends to perform better than barnyardgrass in the initial stage of crop growth, when under equivalent plant density. However, barnyardgrass is usually present in much higher plant density than crop plants in fields traditionally cropped with rice. Thus, efficient control of barnyardgrass should be accomplished to avoid damage to rice crop by competition for environmental resources.

关键词： Echinochloa crusgalli Intermittent Irrigation Oryza sativa