RESUMO A solução fundamental para o problema do entupimento do emissor é explorar o projeto ideal da estrutura do emissor e melhorar sua capacidade anti-entupimento. O objetivo da pesquisa foi selecionar a forma estrutural ideal do caminho de fluxo do emissor em sistemas de irrigação por gotejamento utilizando fontes de água de qualidade inferior, proporcionando suporte teórico para melhorar a capacidade anti-obstrução do próprio emissor e para o projeto de novos produtos de emissores. A seleção da estrutura do caminho do fluxo do emissor não tem sido conduzida com base na determinação do modelo de simulação apropriado com a condição complexa de qualidade da água. Para tanto, determinou-se o modelo de movimento interno do fluido adequado do emissor, e avaliou-se de forma abrangente o desempenho hidráulico e o desempenho anti-entupimento das cinco estruturas representativas da trajetória de fluxo no país e no exterior, e finalmente determinou-se a estrutura ótima da trajetória de fluxo do emissor. Os resultados da pesquisa indicaram que o modelo RNG k-ε foi o mais adequado para simular a área do fluxo no emissor por meio da análise abrangente da lacuna entre os valores simulados e os valores medidos, da precisão do cálculo e da eficiência computacional. A trajetória de fluxo fractal foi relativamente ótima para o desempenho hidráulico e para o desempenho anti-entupimento. Este estudo pode fornecer suporte teórico para melhorar a própria habilidade anti-obstrução do emissor e o projeto de novo produto de emissor. antientupimento. antientupimento anti entupimento. inferior antiobstrução obstrução emissores tanto determinouse determinou se avaliouse avaliou exterior kε k ε medidos computacional

ABSTRACT The fundamental solution to the problem of emitter clogging is to explore the optimal structure design of emitter and improve its anti-clogging ability. The research objective was to select the optimal structural form of the emitter flow path in drip irrigation systems using inferior water sources, which can provide theoretical support for improving the anti-clogging ability of the emitter itself and designing new emitter products. The selection of the flow path structure of the emitter has not been conducted on the basis of determining the appropriate simulation model with the condition of complex water quality. Therefore, the appropriate internal fluid movement model of the emitter was determined, the hydraulic performance and anti-clogging performance of the five nationally and internationally representative flow path structures were comprehensively evaluated, and finally the optimal structure of the emitter flow path was determined. The research results indicated that RNG k - ε model was the most suitable to simulate the flow field in the emitter by comprehensive analysis of the gap between simulated values and the measured values, the calculation accuracy and computational efficiency. The fractal flow path was relatively optimal for hydraulic performance and for anti-clogging performance. This study can provide theoretical support for improving the anti-clogging ability of the emitter itself and the design of the new emitter product. anticlogging anti sources products quality Therefore determined evaluated efficiency product

ABSTRACT. This work aims to report the phytoplankton species composition and cell density in the Mazatlán coastal region (eastern entrance of the Gulf of California (GC), Mexico) during the strong El Niño event of 2023. Surface water samples (at 2 m depth) for phytoplankton cell determinations were collected in December of 2023, a month in which the numerical value of the Oceanic Niño Index was 2.0. The results showed a total of 197 species, including 113 diatoms (with a total cell density of 51,444 cells L-1), 76 dinoflagellates (with a total cell density of 31,260 cells L-1), four silicoflagellates (with a total cell density of 420 cells L-1), two cyanobacteria (with a total cell density of 2,020 cells L-1), one Euglenophyta (with a total cell density of 900 cells L-1) and one ciliate (with a total cell density of 7,820 cells L-1). The diatom Dactyliosolen phuketensis (B.G. Sundström) G.R. Hasle, 1996 and the dinoflagellate Gyrodinium fusiforme (Kofoid & Swezy, 1921) presented the highest cell densities with 4,100 and 5,900 cells L-1, respectively, species that have been previously reported in high abundances in Mexican waters in years of warming events, including El Niño. The results presented here contribute to understanding the effects of strong El Niño events on the phytoplankton community structure of the southeastern GC. This topic still needs to be fully addressed. This study also provides an update on the taxonomic lists available for the region of a group of organisms whose nomenclature has been constantly changing in recent years.

Abstract Nowadays, despite the implementation of new wind farms in Brazil, it still is difficult to form partnerships with companies in the sector, which significantly contributes to the gap in information provided by national literature and the lack of knowledge about the mechanical behavior of wind turbines subjected to transient wind effects. Therefore, through a Research and Development Project to optimize and improve modeling in wind systems, the Brazilian electric power company Eletrobras Furnas aims to facilitate the construction of smaller wind turbines to supply energy to regions far from the Brazilian coast that do not have high generation potential due to the incidence of low-speed winds. Two relevant aspects directly linked to the performance of this kind of structures are: (i) determining their natural frequency and (ii) ensuring that this frequency does not coincide with any external vibration frequency that the structure may experience in its lifetime. Wind turbines are complex systems with many degrees of freedom and their own frequencies associated with the respective mode shapes in which they naturally vibrate. These frequencies are inversely related to the mass and directly related to the stiffness of the structure. Thus, through numerical modeling using the Finite Element Method, the present article aims to list some of the main factors that can affect the prediction of the natural frequency of a real-scale wind turbine prototype and to evaluate its dynamic behavior, considering its rotor revolution frequency, its blade passing frequency and the wind characteristics of its operating area. Nowadays Brazil sector effects Therefore lowspeed low speed winds i (i ii (ii lifetime vibrate Thus Method realscale real scale area

Abstract This article presents a formulation for the optimization problem that minimizes the CO2 emission of pile caps with variations of geometry and pile position. The problem is defined by the design variables: concrete pile cap dimensions, rebar ratio, concrete compressive strength, the number of piles, the diameter, and length. The environmental impact was chosen as the objective function, taking CO2 emission as the main parameter. The design procedure was based on the ABNT NBR 6118:2014 (2014), and by the formulation proposed by Blévot & Frémy (1967). Also, the soil structure interaction between the cap and the piles was considered in the optimization problem. The problem was implemented using MATLAB (2016) and solved via a Genetic Algorithm native to the program. Results obtained from numerical examples were compared with structural designs solutions located in the Grande Vitória metropolitan area, Espírito Santo, Brazil and validated with a commercial software. The analyses indicate that design optimizations of pile caps considering the compressive strength of concrete, the diameter and length of piles and the optimal geometry of the pile caps may lead to significant reductions of material consumption, and consequently, a reduction of environmental impacts. CO position variables dimensions ratio function parameter 61182014 6118 2014 6118:201 2014, , (2014) 1967. 1967 . (1967) Also 2016 (2016 program area Santo software consumption consequently impacts 6118201 611 201 6118:20 (2014 196 (1967 (201 611820 61 20 6118:2 19 (196 (20 61182 6 2 6118: 1 (19 (2 (1 (

Abstract Topological indices are numerical values related to a chemical structure that describes the correlation of chemical structure with different physical properties and chemical reactions. Glass has wide applications in architecture, tableware, optics, and optoelectronics. In this article, first, the mathematical relationship between M-polynomial and Banhatti indices such as K-Banhatti, δ-Banhatti, and hyper δ Banhatti indices are obtained. Then using M-polynomial, Banhatti indices are obtained.

Abstract This work aims the assessment of the dynamic structural response of reinforced concrete floors subjected to rhythmic human activities, based on the use of biodynamic models, in order to consider the people-structure interaction effect. Initially, an experimental modal analysis on the investigated floor , with dimensions of 16m x 35m, was performed, in order to identify and assess the global dynamic behaviour of the structure. In sequence, a finite element model was developed and calibrated through experimental results. After that, based on forced vibration analyses, the floor dynamic response was determined (displacements and accelerations). It is concluded that the biodynamic systems modelling induced significant attenuations on the structural response when compared to those calculated based on the use of traditional “only force” models. activities models peoplestructure people structure effect Initially m 35m performed sequence results analyses displacements accelerations. accelerations . accelerations) only force

Resumo Este trabalho tem como objetivo a avaliação da resposta dinâmica de pisos de concreto armado submetidos a atividades humanas rítmicas, com base no uso de sistemas biodinâmicos, a fim de analisar o efeito de interação pessoa-estrutura. Inicialmente, realizou-se uma análise modal experimental sobre o piso investigado, com dimensões de 16m x 35m, visando identificar e avaliar o comportamento dinâmico global da estrutura. Em seguida, um modelo de elementos finitos foi desenvolvido e calibrado com base nos resultados experimentais. Posteriormente, a partir das análises de vibração forçada, a resposta dinâmica do piso foi determinada (deslocamentos e acelerações). Conclui-se que a modelagem dos sistemas biodinâmicos induziu atenuações significativas sobre a resposta estrutural quando comparadas àquelas calculadas via utilização de modelos tradicionais de força-rítmica. rítmicas pessoaestrutura. pessoaestrutura pessoa estrutura pessoa-estrutura Inicialmente realizouse realizou se investigado m 35m seguida experimentais Posteriormente forçada deslocamentos acelerações. acelerações . acelerações) Concluise Conclui forçarítmica. forçarítmica força rítmica. rítmica força-rítmica

Abstract The construction of high-rise buildings has emerged as a constructive trend worldwide, and excessive vibration problems due to wind actions are becoming increasingly frequent. The Brazilian design standard NBR 6123 recommends that the transfer of wind actions used for structural analysis be carried out based on the pressure coefficients along the building facades for static analyses and considers their non-deterministic dynamic behaviour through a stochastic modelling method of the wind velocity field. To present an alternative approach to this methodology, this study aims to investigate the non-deterministic dynamic structural response of a real reinforced concrete building, considering the soil-structure interaction effect, using the pressure coefficients obtained through different methodologies such as numerical simulations using Computational Fluid Dynamics (CFD), international databases, and the recommendations of the Brazilian standard NBR 6123. highrise high rise worldwide frequent 612 nondeterministic non deterministic field methodology soilstructure soil structure effect CFD, CFD , (CFD) databases 61 (CFD 6

Resumo A construção de edifícios altos tem se mostrado uma tendência construtiva ao redor do mundo, e vibrações excessivas oriundas das ações do vento tem se tornado cada vez mais frequentes. A norma brasileira de projeto NBR 6123 recomenda que a transferência das ações de vento utilizadas para análise estrutural seja realizada com base nos coeficientes de pressão ao longo das fachadas do edifício, para análises estáticas, e considera o seu comportamento dinâmico não determinístico através de um método de modelagem estocástica do campo de velocidade do vento. Objetivando apresentar uma abordagem alternativa para esta metodologia, este estudo tem como objetivo investigar a resposta estrutural dinâmica não determinística de um edifício real de concreto armado, considerando o efeito da interação solo-estrutura, utilizando coeficientes de pressão obtidos por intermédio de metodologias distintas, tais como: simulações numéricas utilizando CFD (Computational Fluid Dynamics), bases de dados internacionais, e utilizando as recomendações da norma brasileira NBR 6123. mundo frequentes 612 estáticas metodologia armado soloestrutura, soloestrutura solo estrutura, estrutura solo-estrutura distintas Computational Dynamics, Dynamics , Dynamics) internacionais 61 6

Abstract Modern non-destructive investigation techniques and computational tools for nonlinear analysis allow understanding the structural behavior and damage of existing buildings, aiming at the least possible extent of intervention. Careful and minimal intervention is essential to preserve the authenticity of the built cultural heritage. An investigation with a historical, experimental, and numerical approach was carried out in the Theatro Municipal do Rio de Janeiro, in Brazil, a building with an eclectic architecture from the beginning of the twentieth century. Its masonry domes and vault have paintings by renowned artists on their intrados and were strengthened in the 1970s. The adopted methodology was based on anamnesis, characterization and observation of the structure employing non-destructive tests, and on the assessment of its vulnerability by nonlinear analyses of calibrated numerical models. Several hypotheses of differential settlement under gravitational actions were investigated, seeking to reproduce the cracking pattern and to identify the causes of damage to the masonry domes and vault before the strengthening. The nonlinear analysis of the structure allowed to evaluate the causes of the observed damage, assess the level of safety, identify the most vulnerable parts, and characterize the collapse mechanisms, in addition to demonstrating the efficiency of the intervention measures adopted in the past. nondestructive non destructive buildings heritage historical experimental Janeiro Brazil century 1970s s anamnesis tests models investigated strengthening safety parts mechanisms past

Resumo Técnicas modernas de investigação não destrutiva e ferramentas computacionais para análise não linear permitem compreender o comportamento estrutural e danos em edifícios existentes, visando a menor intervenção possível. A intervenção cuidadosa e mínima é essencial para preservar a autenticidade do patrimônio cultural construído. Uma investigação de abordagem histórica, experimental e numérica foi realizada no Theatro Municipal do Rio de Janeiro, no Brasil, edifício de arquitetura eclética do início do século XX. Suas cúpulas e abóbada em alvenaria possuem pinturas de renomados artistas no intradorso e foram reforçadas na década de 1970. A metodologia adotada baseou-se na anamnese, caracterização e observação da estrutura por meio de ensaios não destrutivos e na avaliação de sua vulnerabilidade por análises não lineares de modelos numéricos calibrados. Diversas hipóteses de recalque diferencial sob ações gravitacionais foram investigadas, buscando reproduzir o padrão de fissuração e identificar as causas dos danos nas alvenarias antes do reforço. A análise não linear da estrutura permitiu avaliar as causas dos danos observados, estimar o nível de segurança, identificar as partes mais vulneráveis e caracterizar os mecanismos de colapso, além de demonstrar a eficácia das medidas de intervenção adotadas no passado. existentes possível construído histórica Janeiro Brasil XX 1970 baseouse baseou se anamnese calibrados investigadas reforço observados segurança colapso passado 197 19 1

Abstract In civil engineering, the stability of many structures depends on the physical properties of the contact between the concrete seated on the rocky foundation surface. Usually, they are critical structures of great importance to society, such as: bridges, tunnels and dams. Thus, the shear behavior of rock-concrete joints is a key factor of the structural stability. The method of cohesive zones (CZM) allows to simulate the beginning of the formation of a crack and its propagation, without knowing the crack location or when it will start. Thus, in this work, a numerical model was developed capable of simulating the failure due to interfacial delamination of the contact between a structure formed by mortar seated on a rocky granite leaning surface. The calibration of the numerical model was performed using the experimental test results of simple compression on a block of rock in contact with the mortar by an inclined interface. The test was monitored using a high-resolution digital camera. The data were processed using the digital image correlation method (DIC) to obtain displacement data of the laboratory test. The DIC results were used to calibrate the nonlinear numerical model of the test using the bilinear method of cohesive zone in the rock-mortar interfacial contact elements. By a parametric analysis varying the maximum shear stress parameter of the contact cohesive elements, the bilinear law was adjusted (Maximum tensile stress and critical displacement and damage rate). Indirectly, the rate of release of energy of critical deformation from the rupture of the contact was also estimated. engineering surface Usually society as bridges dams Thus rockconcrete CZM (CZM propagation start work interface highresolution high resolution camera (DIC rockmortar elements Maximum rate. . rate) Indirectly estimated

Resumo Na engenharia civil, a estabilidade de muitas estruturas depende das propriedades físicas do contato entre o concreto assentado na superfície rochosa de fundação. Geralmente são estruturas críticas e de grande importância para a sociedade, tais como: pontes, túneis e barragens. Assim, o comportamento ao cisalhamento das juntas rocha-concreto é um fator chave da estabilidade estrutural. O método das zonas coesivas (MZC) permite simular o início da formação de uma fissura e a sua propagação, sem saber a localização da fissura ou quando esta irá começar. Assim, neste trabalho foi desenvolvido um modelo numérico capaz de simular a ruptura por descolamento interfacial do contato entre uma estrutura formada por argamassa assentada sobre uma superfície inclinada de granito rochoso. A calibração do modelo numérico foi realizada através dos resultados de ensaios experimentais de compressão simples sobre um bloco de rocha em contato com a argamassa por uma interface inclinada. O teste foi monitorado por meio de uma câmera digital de alta resolução. Os dados foram processados utilizando o método de correlação de imagens digitais (CID) para obtenção dos dados de deslocamento do ensaio laboratorial. Os resultados do método CID foram utilizados para calibrar o modelo numérico não linear do ensaio utilizando o método bilinear de zona coesiva nos elementos de contato interfacial rocha-argamassa. Através de uma análise paramétrica variando o parâmetro de tensão cisalhante máxima dos elementos coesivos de contato, determinou-se a lei bilinear ajustada (tensão máxima de tração, deslocamento crítico e taxa de dano). Indiretamente, também foi estimada a taxa de liberação de energia de deformação crítica proveniente da ruptura do contato. civil fundação sociedade como pontes barragens Assim rochaconcreto estrutural MZC (MZC propagação começar rochoso resolução (CID laboratorial rochaargamassa. rochaargamassa argamassa. rocha-argamassa determinouse determinou se tração dano. dano . dano) Indiretamente

Abstract The mechanical degradation of concrete structures is a phenomenon dependent on the material heterogeneity observed at mesoscale. As the mechanical degradation is a localized phenomenon, structural members and structures may be simulated using the concurrent multiscale analysis technique. Thus, only the most critical regions are modeled in mesoscale, reducing the computational cost compared to the simulation of the entire structure at this scale. This work presents two contributions in concurrent multiscale analysis. The first contribution introduces an alternative representation of the mesoscale interfacial transition zone (ITZ) of the concrete together with a strategy that allows modeling particles (coarse aggregates) without degrees of freedom. The resulting ITZ representation allows the simulation of more realistic discrete cracks in concrete modeling. The second contribution uses particle-like elements without degrees of freedom as coupling elements to model non-matching meshes between different media. The proposed coupling technique does not add degrees of freedom and does not use penalty or Lagrange Multipliers methods. Experimental and numerical results are used in order to validate the proposed multiscale formulation regarding concrete specimen simulations. Thus scale (ITZ coarse aggregates particlelike particle like nonmatching non matching media methods simulations

Resumo A degradação mecânica de estruturas de concreto é um fenômeno dependente da heterogeneidade do material observada em mesoescala. Como a degradação mecânica é um fenômeno localizado, elementos estruturais e estruturas podem ser simulados usando a técnica de análise multiescala concorrente. Assim, apenas as regiões mais críticas são modeladas em mesoescala, reduzindo o custo computacional em comparação com a simulação de toda a estrutura nessa escala. Este trabalho apresenta duas contribuições para a estratégia de análise multiescala concorrente. A primeira contribuição apresenta uma representação alternativa da zona de transição interfacial da mesoescala (ITZ) do concreto juntamente com uma estratégia que permite modelar partículas (agregados graúdos) sem graus de liberdade. A representação da ITZ resultante permite a modelagem de fissuras discretas mais realistas na simulação de concreto. A segunda contribuição usa elementos semelhantes a agregados sem graus de liberdade como elementos de acoplamento para modelar malhas não conformes entre diferentes meios. A técnica de acoplamento proposta não adiciona graus de liberdade e não utiliza métodos de penalização ou multiplicadores de Lagrange. Resultados experimentais e numéricos são usados para validar a formulação multiescala proposta aplicada em simulações de amostras de concreto. localizado concorrente Assim escala (ITZ graúdos meios Lagrange

Abstract Reinforced concrete structures must be designed in a manner that assures an acceptable level of safety and performance. However, accidents still occur nowadays causing interdiction, financial losses, or even human casualties. Therefore, succinct studies are required to give answers to such an undesirable situation, helping to prevent repetition and enlightening new design and construction methods. This paper analyzes the failure mechanism in a large reinforced concrete panel composed of one L-shaped cantilevered wall and structural walls in Campinas. The investigation was carried out using in-situ destructive and non-destructive tests and also through numerical simulation. In-situ tests revealed that the region where the fracture happened had no sufficient resisting steel area. The fracture line developed through the end of the wall’s horizontal rebars anchored within the column. It was concluded that the reinforced concrete panel failure happened due to structure misconception and incorrect design, once columns stirrups were responsible for the equilibrium of the cantilevered part of the building, as demonstrated by the nonlinear finite element study and in-situ investigations. performance However interdiction losses casualties Therefore situation methods Lshaped L shaped Campinas insitu situ nondestructive non simulation Insitu In area s column building investigations

Resumo Estruturas de concreto armado devem ser projetadas de maneira a garantir um nível aceitável de segurança e desempenho. Porém, acidentes ainda são observados atualmente causando interdições, perdas financeiras, e até mesmo humanas. Portanto, estudos aprofundados são necessários para responder a essas situações indesejáveis, prevenindo sua repetição e desenvolvendo novas formas de dimensionamento e construção. O presente trabalho analisa o mecanismo de falha observado em um extenso painel de concreto armado composto por uma parede em balanço apoiada em um pilar parede, localizados na cidade de Campinas. As investigações foram realizadas in loco utilizando testes destrutíveis e não destrutíveis e também via simulações numéricas. Os testes in loco revelaram que a região onde ocorreu a ruptura localizada não possuía quantidade suficiente de armadura metálica. A linha de fratura se desenvolveu no término das armaduras horizontais da parede. Concluiu-se que a falha do painel ocorreu devido a erros de concepção e dimensionamento, dado que os estribos do pilar-parede foram responsáveis pelo equilíbrio da parte em balanço da edificação, como ficou demonstrado pelo estudo utilizando análise não linear via Elementos Finitos e pelas investigações in-loco. desempenho Porém interdições financeiras humanas Portanto indesejáveis construção Campinas numéricas metálica Concluiuse Concluiu pilarparede edificação inloco. inloco loco. in-loco

Abstract The bi-axial hollow slab is the result of applying a technology that removes concrete from the least useful region and replaces it with hollow plastic spheres. This technique leads to material economy and self-weight saving, without considerable inertial loss, enabling larger and more flexible spans. Consequently, these spans are vulnerable to unwanted vibrations and dynamic acceleration caused by external actions, such as movements produced by human activity. This way, understanding the dynamic behavior of this technology and confronting it with normative limits on the project phase is essential for a good performance in the serviceability limit state, bringing comfort to the user. This paper studies the dynamic behavior of a bi-axial hollow slab submitted to human actions, such as jumping, dancing, clapping, moving the body, and moving and clapping at the same time. For that, this work made a numerical model of the structure and applied dynamic actions to it. The numerical results show that, for most of the actions, normative limits are satisfied, but the slab presents excessive accelerations in the case of jumping and dancing. biaxial bi axial spheres selfweight self weight saving loss Consequently activity way state user dancing body time satisfied

Resumo Laje bidirecional oca resulta da aplicação de uma tecnologia que remove concreto de regiões em que ele é pouco útil e coloca esferas plásticas ocas no seu interior. Essa característica gera economia de material e redução de peso próprio, sem perder considerável inércia, possibilitando vãos maiores e mais flexíveis, que, consequentemente, são suscetíveis a vibrações e acelerações dinâmicas indesejáveis causadas por ações externas, como os movimentos produzidos pela atividade humana. Dessa forma, entender o comportamento dinâmico desta tecnologia e confrontar com limites normativos, ainda na fase de projeto, é fundamental para um bom desempenho no estado limite de serviço, trazendo conforto ao usuário. A presente pesquisa visa estudar o comportamento dinâmico de uma laje bidirecional aliviada submetida às ações humanas de pular, dançar, bater palmas, balançar o corpo e bater palmas balançando o corpo. É realizada a modelagem numérica da estrutura e nela são aplicadas as ações dinâmicas. Os resultados numéricos mostram que, para a maioria das ações (bater palmas, balançar o corpo e bater palmas balançando o corpo) os serviços limites normativos são atendidos, entretanto, a laje bidirecional aliviada apresenta acelerações excessivas para as ações de pular e dançar. interior próprio inércia flexíveis consequentemente externas humana forma projeto serviço usuário dançar atendidos entretanto

Abstract Liquid composite armor has demonstrated excellent performance in protecting against shaped charge jets. Currently, most existing theoretical calculation models for the velocity range of the disturbed jet approximate the cone angle of the shockwave front as the Mach angle. However, indiscriminately equating the cone angle of the shockwave front with the Mach angle can lead to significant errors in the calculated velocity range of the disturbed jet. To address this issue, this study focuses on investigating the variation of the cone angle of the shockwave front within the liquid composite protective structure. Firstly, a dimensional analysis was conducted to determine the functional relationship between the cone angle of the shockwave front and relevant parameters. Then, the process of jet penetrating liquid composite protective structure was simulated by Autodyn. The results demonstrated that the normalized cone angle solely depends on the normalized diameter within the critical angle. By fitting the simulation data, the formula for calculating the cone angle of the shockwave front was derived. jets Currently However issue Firstly parameters Then Autodyn data derived

Abstract A damage detection method based on the quadratic correlation function of strain responses (QCoS) and pattern matching degree (PMD) is proposed in the present study. For this method, only QCoS is calculated in time domain by strain responses, and there is no need for modal parameter extraction and analytical model of structures. It is proved that QCoS is the function of modal parameters of structures, such as natural frequency, mode shape and damping ratio. Numerical simulations of a simply supported steel beam are analyzed for illustrating the effect of excitation position, reference point and damage level on QCoS, respectively. The results show that QCoS is sensitive to local damage in the structure and robust to measurement noise. Therefore, QCoSs are used to construct the damage feature vector. The damage detection is performed by comparing the damage feature vectors before and after the structural damage. Three simply supported aluminum beams are tested in the laboratory to demonstrate the effectiveness and practicability of the proposed method. (QCoS PMD (PMD study structures frequency ratio position respectively noise Therefore vector

Abstract Large meteorite impacts release kinetic energy that induces rock deformation, high temperatures and fluid circulation during the cratering process. To understand the correlation between rock deformation and fluid circulation, it is relevant to investigate post-impact hydrothermal flux and its relation to the local geology. The Cerro do Jarau impact structure is a ~13.5 km diameter impact structure located in southern Brazil and formed on Cretaceous continental flood basalts of the Serra Geral Formation and underlying sedimentary strata. This study collected ground gamma-ray data over the structure and produced K, eTh and eU concentrations, eTh/K ratio and F-factor maps to characterize it in terms of its radiometric signatures and their respective spatial distribution. A general decrease in the concentration of the three elements was observed from the outer-rim towards the center of the crater. The central area is defined by very low radiometric values, with relatively high K values, thus indicating the occurrence of K-bearing rocks. Numerical simulations using the HYDROTHERM 3 code showed the fluid circulation pattern over the impact structure. Data interpretation resulted in a scenery consistent with potential fluid remobilization within the impact structure related to hydrothermal processes in the late stages of the crater formation process. process postimpact post geology 135 13 5 ~13. strata gammaray gamma ray concentrations eThK Ffactor F factor distribution outerrim outer rim values Kbearing bearing rocks 1 ~13 ~1 ~