Disertacijoje aprašomas metodas, sukurtas vertinti ypatingųjų poveikių statiniams keliamą riziką. Darbe pateikti trys šio metodo taikymo pavyzdžiai. Disertaciją sudaro įvadas, penki skyriai, išvados, literatūros šaltiniai, autoriaus publikacijų sąrašas ir penki priedai. Pirmajame skyriuje apžvelgiama mokslinė literatūra, kurioje tiriami rizikos vertinimo metodai ir aptariama jų taikymo konstrukcijoms skaičiuoti galimybė. Pateikiama trumpa ypatingųjų poveikių klasifikacija bei konstrukcijų, kurias jie gali paveikti, pažeidžiamumo modeliavimas. Antrajame skyriuje aprašomas metodas, sukurtas ypatingųju poveikių keliamų konstrukcijų pažaidų tikimybėms vertinti. Metodas derina statybinių konstrukcijų patikimumo teorijos ir Bajeso statistinės teorijos priemones. Jis gali būti taikomas tiek projektuojant konstrukcijas, tiek vertinant pramoninių objektų riziką. Trečiajame skyriuje aprašoma, kaip taikyti siūlomą metodą vertinant medinėms konstrukcijoms keliamą gaisro riziką. Ta rizika išreiškiama gaisro pažeistos konstrukcijos suirimo tikimybe, kuri yra vertinama apriorine ir aposteriorine tankio funkcijomis, skaiciuojamomis Bajeso statistinės teorijos priemonėmis. Šiame skyriuje nagrinėjama medinė gaisro veikiama pramoninio pastato stogo konstrukcijos sija. Gaisro poveikis modeliuojamas maža statistine gaisro charakteristikų imtimi. Ketvirtajame skyriuje pateiktas siūlomo metodo taikymas projektuojant sprogimo veikiamą apsauginį barjerą. Atsižvelgiama i barjero elementų mechaninio... [toliau žr. visą tekstą] / The dissertation presents a method developed for assessing the risk to constructed facilities posed by accidental actions. The proposed method is applied to the analysis of structures subjected to accidental actions induced by fire, explosion and extreme wind. The dissertation consists of introduction, five chapters, conclusions, lists of references and papers published by the author of the dissertation, as well as five annexes. Chapter 1 presents a review of published work on the assessment of risk to structures and non-structural property posed by accidental actions. The review covers general aspects of risk assessment and application of risk analysis tools to the analysis and design of structures. The core of the review is an application of Bayesian methods, which prevail in the field of risk assessment, to a risk-based structural analysis. Chapter 2 proposes a method developed for the assessment of damage to structures from accidental actions. This method combines structural analysis with Bayesian handling of information related to accidental actions and response of structures to these actions. The method allows to estimate probabilities of the damage to structures caused by accidental actions. Chapter 3 deals with an application of the proposed method to the estimation of fire risk to structures. It is shown how to apply this method to the estimation of failure probability of a timber beam damaged by fire in an industrial building. This chapter shows how to handle... [to full text]

The Ph.D. thesis deals with extreme wind gust analysis over the area of the Czech Republic. The first part of the thesis deals with processing of wind measurements, in particular maximum wind gusts measurements. Analysis of high-frequency wind measurement using 3-D sonic anemometer on the Kopisty station is included. Homogenization of the highest daily wind gusts was performed. Descriptive statistical analysis of measured wind gust values was performed. The following part of the thesis describes statistical theory of extreme values and discusses its applicability to wind gust data. Some theoretical findings were obtained. Numerous numerical experiments were performed focused on evaluation of proposed method. In the last part of the thesis station measurements were processed using the proposed methods and a model of dependence between extreme and mean wind climate was derived. The model was applied to the map of mean wind climate calculated earlier on the Institute of Atmospheric Physics and thus a map of extreme wind climate was obtained. The accuracy of this map was estimated. The map was compared with other maps of extreme wind calculated by other authors earlier.

Thesis (MScEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Tropical cyclones are synoptic scale rotating storms capable of generating intense wind speeds and rainfall with potentially devastating social and economic consequences. In addition to abnormally high winds and rainfall, the associated storm surge and extreme waves can lead to severe coastal erosion, damage to coastal property and inundation. A good understanding of the risk exposure to these events is therefore of great importance to planners and designers of coastal infrastructure in vulnerable regions. Probabilistic approaches have been routinely adopted for the calculation of extreme tropical cyclone induced wind speeds, with significant developments in these techniques over the last few decades. While the application of these approaches has become widely adopted in regions such as the North Atlantic, North Pacific and South Pacific Oceans, relatively little attention has been paid to the South-West Indian Ocean. This thesis focusses on the quantification of the risk exposure to tropical cyclones over the South-West Indian Ocean, using current state-of-the-art techniques. The primary results of the thesis are extreme wind speed maps at various return periods of interest for engineering design. Best track data for the South-West Indian Ocean, as archived by the Joint Typhoon Warning Centre (JTWC), has been used as the primary dataset forming the basis of this study. These data provide estimates of the location and intensity of historical tropical cyclones at six hourly intervals. Location data are provided as estimates of longitude and latitude of the eye, while intensity data are provided as estimates of the maximum sustained surface (10 m elevation) wind speed and/or minimum central pressure. The modelling of tropical cyclone wind fields has been carried out using both the Holland (1980) and the Willoughby et al. (2006) parametric wind field models. Using the limited information available in the best track data as input to the model, surface wind fields which reasonably resemble those of actual storms have been generated. Both considered parametric wind field models have been shown to yield reasonable wind speeds and directions when compared with measurements. Of the two considered models the Willoughby et al. (2006) model has been shown to provide the best fit to historical wind speed measurements. Extreme value analyses of tropical cyclone induced wind speeds based on historical data alone have been shown to lead to potentially large errors, owing to the small sample size of the historical data. This highlights the need to augment the historical database through a probabilistic approach. Largely following the methods described in Powel et al. (2005) and Emanuel et al. (2006), a synthetic track model for the South-West Indian Ocean has been developed. The objective of the synthetic track model is to simulate thousands of years of tropical cyclone tracks, thereby circumventing errors induced by small sample sizes in the available historical best track data. The synthetic track model developed as part of this study is a Markov chain model, capable of simulating track propagation and intensity evolution along the track, from track genesis through to termination. The model is purely statistical, based on properties derived from the historical best track data. Adjustments have however been made to account for physical limitations such as those imposed by the equator and the maximum potential intensity which an event can attain. The statistical characteristics of synthetic tracks have been shown to agree well with those of the historical population. Applying the Willoughby et al. (2006) wind field model along synthetic tracks has enabled the simulation of 5 000 years of tropical cyclone induced wind speeds at any location of interest in the South-West Indian Ocean. Applying calculations on a 1 degree geographical grid, wind speed maps corresponding to return periods of 50, 100, 200 and 500 years have been generated for the South-West Indian Ocean. Extreme wind speeds along coastal regions provide valuable input for the design of coastal infrastructure in the region. / AFRIKAANSE OPSOMMING: Tropiese siklone is sinoptiese orde roterende storms wat in staat is om aansienlike windspoed en reënval, tot gevolg te hê met potensiële vernietigende sosiale en ekonomiese gevolge. Benewens die abnormale sterk winde en hoë reënval kan die verwante stormdeinings en vloedgolwe lei tot ernstige kus-erosie, skade aan kusfront-eiendom en oorstromings. ‘n Goeie begrip van die risiko-blootstelling aan hierdie gebeurtenisse is daarom van groot belang vir die beplanners en ontwerpers van kus-infrastruktuur in kwesbare gebiede. As gevolg van die beduidende ontwikkeling van probabilistiese benadering tot die berekening van windspoed wat veroorsaak word deur ekstreme tropiese siklone, word hierdie tegnieke huidiglike op ‘n roetine basis aangewend. Terwyl die toepassing van hierdie benaderings wyd aanvaar word in gebiede soos die Noord-Atlantiese, Noordelike- en Suidelike Stille Oseaan, word relatief min aandag gegee aan die Suid-Westelike Indiese Oseaan. Hierdie tesis fokus op die kwantifisering van die risiko-blootstelling aan tropiese siklone in die Suid-Westelike Indiese Oseaan met die gebruik van die huidige gevorderdste tegnieke. Die primêre resultaat van die tesis is uiterste wind spoed kaarte vir ‘n verskeindenheid herhaal periodes wat van belang in vir engenieursontwerp. Beste roete-ata vir die Suid-Westelike Indiese Oseaan, soos voorsien deur die Gesametlike Tifoon Waarskuwing Sentrum (JTWC), is gebruik as die primêre data stel wat die basis vorm van hierdie studie. Hierdie data gee die beste skattings van die ligging (lengte- en breedtegraad), en intensiteit (maksimum volgehoue oppervlak (10m hoogte) wind spoed en/of sentrale druk tekort) van historiese tropiese siklone teen ses-uurlikse intervalle. Die modelering van tropiese sikloon windvelde was uitgevoer met die gebruik van die Holland (1980) en die Willoughby et al. (2006) parametriese windveldmodelle. Met die gebruik van beperkte inligting wat beskikbaar is in die beste roete data as invoer vir die model, was oppervlak wind velde gegenereer wat ‘n billike ooreenstemming het met die van werklike storms. Beide tegnieke se parametriese windveldmodelle is al bewys om redelike akkurate windspoed en windrigtings te lewer in vergelyking met waargenome waardes. Van die twee modelle het die Willoughby et al. (2006) model se resultate die beste ooreenstemming gewys met historiese wind spoed metings. Dit is al uitgewys dat uiterste waarde-analises van tropiese sikloon veroorsaakte windspoed moontlik kan lei tot groot foute in die resultate as gevolg van die klein monster-grootte van die historiese data. Dit beklemtoon die noodsaaklikheid om die historiese databasis aan te vul met behulp van probabilistiese metodes. Die metodes soos beskryf deur Powel et al. (2005) en Emanuel et al. (2006) is hoofsaaklik gebruik om ‘n sintetiese roete-model vir die Suid-Westelike Oseaan te ontwikkel. Die doelwit van die sintetiese roete model is om duisende jare se tropiese sikloonroetes te produseer, en in effek foute te vermy as gevolg van die gebruik van klein monster groottes van die beskikbare historiese beste roete data. Die sintetiese roete model wat tydens hierdie studie ontwikkel is, is ‘n Markov kettingmodel wat in staat is om die roete verspreiding asook die evolusie van intensiteit saam die roete te simuleer vanaf die onstaan tot die beëindiging van die sikloon se roete. Die model is suiwer statisties en is gebasseer op die eienskappe soos afgelei vanaf die historiese beste roete data. Aanpassings is gemaak om rekening te hou van die fisiese beperkings soos die wat opgelê word deur die ewenaar en die maksimum potensiële intensiteit wat ‘n sikloon kan bereik. Dit is voorgelê dat die statistiese einskappe van die sintetiese roetes goed saamstem met die van die historiese populasie. Die toepassing van die Willoughby et al. (2006) wind veld model langs die sintetiese roetes het dit moontlik gemaak om 5000 jaar se windspoed, wat veroorsaak is deur tropiese siklone, te genereer by enige ligging wat van belang is in die Suid-Westelike Indiese Oseaan. Met berekeninge wat op ‘n 1 grade geografiese ruitnet gedoen is, is windspoedkaarte vir herhaal periodes van 50, 100, 200 en 500 jaar opgestel vir die Suid-Westelike Indiese Oseaan. Die uiterste wind spoed in kusgebiede gee waardevolle invoer vir die ontwerp van kus-infrastruktuur in die omgewing.

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-07-12T17:16:49Z No. of bitstreams: 1 ALEXSANDRA BARBOSA SILVA – DISSERTAÇÃO (PPGMET) 2014.pdf: 3417534 bytes, checksum: 6274442eb8a5ef08a937200d6d28903c (MD5) / Made available in DSpace on 2018-07-12T17:16:49Z (GMT). No. of bitstreams: 1 ALEXSANDRA BARBOSA SILVA – DISSERTAÇÃO (PPGMET) 2014.pdf: 3417534 bytes, checksum: 6274442eb8a5ef08a937200d6d28903c (MD5) Previous issue date: 2014-03-11 / CNPq / O foco deste trabalho são as rajadas de vento registradas no Aeroporto Internacional de Salvador no período 2003-2011. Variáveis meteorológicas observadas à superfície na área do aeroporto, imagens de satélites meteorológicos e dados em pontos de grade são utilizados para analisar a variabilidade interanual, sazonal e horária das rajadas, identificar escalas e fatores físicos envolvidos através da análise em componentes principais, e diagnosticar as condições sinóticas de dois episódios selecionados. Foram contabilizadas 63 rajadas de vento, sendo 51% em 2003 e 2007. Ventos do setor sul são os mais frequentes e a frequência horária é mínima entre meia noite e 7 horas da manhã. Nos meses de maio de 2007 e 2009 o número de rajadas é máximo. Os fatores retidos na análise em componentes principais indicam a contribuição das escalas de tempo sinótica e diária nesses meses. O mês de maio de 2007 tem cinco registros de rajadas de vento, nos dias 10 e 11. Dentre elas está a mais intensa do período 2003-2011 (68,5 km/h). No mês de maio de 2009 também há cinco registros, todos no dia 22. A análise sinótica desses dias de rajadas evidencia o papel desempenhado por: (a) um sistema frontal austral no primeiro episódio (10-11 de maio de 2007), e (b) um cavado na área dos ventos alísios, no leste do Nordeste do Brasil, no segundo episódio (22 de maio de 2009). À exceção de uma, todas as rajadas de vento ocorreram na presença de nuvens de convecção profunda (cumulus congestus). A Coordenadoria da Defesa Civil de Salvador (CODESAL) registrou atendimentos nos dias das rajadas de vento associando a ocorrência dos desastres a fatores meteorológicos como ventos fortes. / The focus in this work is the wind gusts registered at the Salvador International Airport during the period 2003-2011. Surface meteorological variables observed within the airport area, meteorological satellite images and gridpoint data are used to analyze the wind gusts interannual, seasonal and hourly variability, to identify scales and physical factors involved by means of the principal component analysis, and to diagnose the synoptic conditions of two selected episodes. A total of 63 wind gusts were found; 51% occurred in 2003 and 2007, altogether. Gusts on the south sector of the wind rose are the most frequent. The hourly frequency of the gusts has a minimum between midnight and 7 A. M. May 2007 and 2009 have the maximum number of wind gusts. The factor loadings retained in the principal component analysis indicate the contribution of the synoptic and daily time scales in these months. On May 2007 there are five wind gusts, on the 10th and 11th, including the strongest of the period of study (68.5 km/h). On May 2009 there are five wind gusts also, on the 22th. The synoptic analysis of these gust days highlights the role played by: (a) an austral frontal system on the first episode (10-11 May 2007), and (b) a trough on the trades over the Northeast Brazil eastern area on the second episode (22 May 2009). All wind gusts, with exception of one, occurred in the presence of deep cumulus clouds (cumulus congestus). The Civil Defense of Salvador (CODESAL) indicates that the disasters registered on these days are due to meteorological factors such as strong winds.

The simultaneous occurrences of several extreme events, known as compound extremes, are often associated with greater impact than univariate extremes. Flooding and windstorms are widespread hazards in Europe which can lead to severe property damage and fatalities. During winter, extreme wind and precipitation often co-occur, since they are associated with a common driver, namely extratropical cyclones. In this project, the occurrences of compound wind and precipitation events in Europe are investigated using the ERA5 reanalysis dataset. The analysis covers the years 1979-2019 with a focus on boreal winter. Areas that experience the highest occurrence of compound wet-windy extremes are the west coast of Norway, the Iberian peninsula, parts of central Europe, and southeast of the Black Sea. A few case studies are discussed with the purpose to give an idea of the magnitude of possible impacts. Further, the relationship between extreme wind and precipitation events and the North Atlantic Oscillation (NAO) is presented. During days with positive NAO, extreme precipitation and wind events occur in the central and northern parts of Europe while the negative phase brings extreme wind and precipitation to the southern parts of Europe. Lastly, a short analysis to discover changes in the occurrences of compound precipitation and wind events for the two periods 1979-1999 and 2000-2019 is performed. The result showed no clear changes. The number of compound extremes does not seem to vary for the two periods. / Olika extrema väderhändelser som sammanfaller orsakar ofta större skada än enskilda extrema händelser på många håll i samhället. Översvämningar och vindstormar är vanligt förekommande i Europa och kan leda till kostsamma skador och dödsfall. Extrema vind-och nederbördshändelser sammanfaller vanligen under vintern eftersom de båda ofta orsakas av Nordatlantiska cykloner, som är vanligast under den årstiden. I detta projekt kartläggs sammanfallande vind- och nederbördshändelser i Europa under vintermånaderna december-februari, med hjälp av ERA5 reanalysdata för åren 1979-2019. Områden med relativt hög förekomst av sammanfallande vind- och nederbördshändelser är Norges västkust, Iberiska halvön, delar av Centraleuropa och östra Turkiet. Några fallstudier kopplade till dessa områden är diskuterade för att ge en uppfattning om konsekvenserna av dessa sammanfallande händelser. Eventuella kopplingar mellan sammanfallande vind- och nederbördshändelser och den Nordatlantiska Oscillationen (NAO) är också undersökt. Under den positiva fasen av NAO sker extrema nederbörd- och vindhändelser i norra och centrala delar av Europa medan den negativa fasen ger extrem vind och nederbörd i de södra delarna av Europa.En kort analys för undersöka om förekomsten av extrema sammanfallande händelser har ändrats genomfördes genom att jämföra andelen sammanfallande händelser under de två perioderna 1979-1999 och 2000-2019. Ingen betydande förändring i andelen sammanfallande händelser mellan dessa perioder hittades.

The introduction of the theoretical part is devoted to the analysis of threats, another part to the rescue of animals. In the next part, I focused on zoological gardens and evacuation of animals. The last chapter of the theoretical part deals with the evacuation of selected species of animals. When selecting individual species, I focused on those that are most represented in Dvorec Zoo. The aim of my thesis was to create an analysis of the preparedness of the selected zoo to selected crisis situations and to identify the risks of evacuation of the zoo. In order to achieve these goals, I have set research questions - how is the zoo prepared for selected crisis situations? And what are the possible risks associated with evacuating selected species? In the second part of my thesis I focused on the research itself, which included an interview with the director of Dvorec Zoo. Based on the interview and my own observation I processed the KARS method. The KARS method has identified 6 risks that could compromise the operation of Dvorec Zoo. These risks include extreme wind, large-scale gas supply disruption, large-scale electricity supply disruption, snow calamity, and extremely low temperatures. Based on the identified risks, I created a plan for MU solution for Dvorec Zoo. In the MU solution plan, I focused primarily on the impacts on operation, planned measures, procedures and responsible people. Dvorec Zoo will, of course, be provided with this plan.

Large-scale testing of low-rise buildings or components of tall buildings is essential as it provides more representative information about the realistic wind effects than the typical small scale studies, but as the model size increases, relatively less large-scale turbulence in the upcoming flow can be generated. This results in a turbulence power spectrum lacking low-frequency turbulence content. This deficiency is known to have significant effects on the estimated peak wind loads. To overcome these limitations, the method of Partial Turbulence Simulation (PTS) has been developed recently in the FIU Wall of Wind lab to analytically compensate for the effects of the missing low-frequency content of the spectrum. This method requires post-test analysis procedures and is based on the quasi-steady assumptions. The current study was an effort to enhance that technique by investigating the effect of scaling and the range of applicability of the method by considering the limitations risen from the underlying theory, and to simplify the 2DPTS (includes both in-plane components of the turbulence) by proposing a weighted average method. Investigating the effect of Reynolds number on peak aerodynamic pressures was another objective of the study. The results from five tested building models show as the model size was increased, PTS results showed a better agreement with the available field data from TTU building. Although for the smaller models (i.e., 1:100,1:50) almost a full range of turbulence spectrum was present, the highest peaks observed at full-scale were not reproduced, which apparently was because of the Reynolds number effect. The most accurate results were obtained when the PTS was used in the case with highest Reynolds number, which was the1:6 scale model with a less than 5% blockage and a xLum/bm ratio of 0.78. Besides that, the results showed that the weighted average PTS method can be used in lieu of the 2DPTS approach. So to achieve the most accurate results, a large-scale test followed by a PTS peak estimation method deemed to be the desirable approach which also allows the xLum/bm values much smaller than the ASCE recommended numbers.