Application of joint refraction and reflection travel time seismic tomography in the area of Colombia-Ecuador zone

Esmeraldas projekt je 3D seizmičko istraživanje iz 2005. godine u području subdukcijske zone blizu granice Kolumbije i Ekvadora koje obuhvaća veći dio područja loma potresa iz 1958. te dijelove većih potresa u zadnjih 120 godina. Geometrija istraživanja postavljena je tako da se uz nailaske refraktiranih valova mogu odrediti nailasci za one reflektirane valove čiji je upadni kut približan ili veći graničnom kutu. Podatke istraživanja prvo su iskoristili García-Cano i sur. [2014] za odredivanje 3D modela brzina P-valova koristeći vremena putovanja refraktiranih valova. Meléndez [2014] je iskoristio podatke od García-Cano i sur. [2014] da testira svoj tomografski program TOMO3D. U ovom radu refrakcijski podaci prethodnih radova korigirani su, te je koristeći TOMO3D program dobiven 3D model brzina P-valova s boljim statističkim rezultatima od prethodnih radova. Zatim su dodana refleksijska vremena putovanja kako bi se testirala združena inverzija programa TOMO3D i odredila geometrija diskontinuiteta na vrhu subducirane litosfere. Dobiveno je poboljšanje modela brzina, dok određena geometrija diskontinuiteta nije zadovoljavajuća. Ipak, položaj diskontinuiteta dovoljno je dobar da se analiziraju brzine iznad njega te da se na taj način provjeri valjanost pretpostavke konstantnog modula smicanja pri određivanju seizmičkog momenta potresa u subdukcijskim zonama. Otkriveno je da postoje znatne lateralne varijacije brzine, što može značiti i velike varijacije modula smicanja.Esmeraldas project is a 3D refraction and wide-angle reflection seismic experiment from 2005 which was conducted in the subduction zone at the border between Ecuador and Colombia. Area of the experiment covers large part of the 1958 earthquake rupture zone and parts of the other large earthquakes in the last 120 years. García-Cano et al. [2014] obtained 3D P-wave velocity model using refraction data from the experiment. Meléndez [2014] used their data to test his tomography code TOMO3D. In this paper refraction data from previous studies were corrected and using TOMO3D 3D P-wave velocity model was obtained with better statistical results than the previous works. Next step was to include the reflection data to test the TOMO3D joint tomography and to obtain reflector geometry. The velocity model was improved, but the final reflector geometry wasn’t satisfactory. The position of the reflector was still good enough to analyze velocities above it and to check the validity of taking constant rigidity value in the process of earthquake seismic momment calculations. Lateral velocity variations do exist and they are big enough that we can talk about possibility of significant lateral variations of rigidity

VERGLEICH DER ANWENDUNG KROATISCHER VORSCHRIFTEN UND DES EUROCODE 8

Opisane su razlike između hrvatskih propisa i Eurokoda 8 (EC8) koje se odnose na proračun konstrukcija visokogradnje na djelovanje potresa. Uspoređeni su modeli armiranobetonskih (ab) konstrukcija dimenzionirani prema oba propisa. Uspoređivani su modeli raznih sustava ab konstrukcija: okvirnih, mješovitih i sa zidovima. Pokazalo se da je postupak prema EC8 složeniji i da zahtijeva više inženjerskog znanja. Rad je dio znanstvenog projekta čiji je cilj prilagodba EC8 našim uvjetima.Differences between Croatian regulations and Eurocode (EC8) with respect to seismic design of structural elements of buildings are described. Reinforced-concrete models of structures designed according to both documents are compared. Models of various reinforced-concrete structural systems are compared: frame models, models with walls and mixed models. The authors demonstrate that the procedure based on EC8 is more complex and that it requires higher level of engineering knowledge. The paper is a part of the research project aimed at adapting EC8 to conditions prevailing in our country.L’article décrit les différences entre les règlements croates et l’Euro code 8 (EC8) relatives au calcul des constructions du bâtiment à l’action des séismes. L’on compare les modèles des constructions en béton armé dimensionnées selon les deux règlements. Les modèles de différents systèmes de constructions en béton armé ont été mis en comparaison : en cadre, aux murs, mixtes. Il s’est révélé que le procédé selon le EC8 était plus complexe et qu’il demandait plus de l’art de l’ingénieur. Cet article fait partie d’un projet scientifique dont l’objectif est l’adaptation de l’EC8 à nos conditions.Es sind Unterschiede zwischen den kroatischen Vorschriften und dem Eurocode 8 (EC8) beschrieben die sich auf die Berechnung von Hochbaukonstruktionen gegen seismische Einflüsse beziehen. Verglichen sind Modelle von Stahlbetonkonstruktionen (Stb), bemessen nach beiden Vorschriften. Es wurden Modelle verschiedener Stb Konstruktionen verglichen: Rahmen, mit Wänden und gemischt. Es zeigte sich dass das Verfahren nach EC8 komplizierter ist und mehr Ingenieurwissen verlangt. Der Artikel ist ein Teil des wissenschaftlichen Projekts dessen Ziel die Anpassung des EC8 an die kroatischen Umstände ist

Design and development of a novel Invasive Blood Pressure simulator for patient's monitor testing

This paper presents a newly-designed and realized Invasive Blood Pressure (IBP) device for the simulation on patient’s monitors. This device shows improvements and presents extended features with respect to a first prototype presented by the authors and similar systems available in the state-of-the-art. A peculiarity of the presented device is that all implemented features can be customized from the developer and from the point of view of the end user. The realized device has been tested, and its performances in terms of accuracy and of the back-loop measurement of the output for the blood pressure regulation utilization have been described. In particular, an accuracy of ±1 mmHg at 25 °C, on a range from −30 to 300 mmHg, was evaluated under different test conditions. The designed device is an ideal tool for testing IBP modules, for zero setting, and for calibrations. The implemented extended features, like the generation of custom waveforms and the Universal Serial Bus (USB) connectivity, allow use of this device in a wide range of applications, from research to equipment maintenance in clinical environments to educational purposes. Moreover, the presented device represents an innovation, both in terms of technology and methodologies: It allows quick and efficient tests to verify the proper functioning of IBP module of patients’ monitors. With this innovative device, tests can be performed directly in the field and faster procedures can be implemented by the clinical maintenance personnel. This device is an open source project and all materials, hardware, and software are fully available for interested developers or researchers.Web of Science201art. no. 25

UNLINEARE ERWIEDERUNG VON KONSTRUKTIONEN BEMESSEN NACH KROATISCHEN UND EUROPÄISCHEN NORMEN

U radu se prikazuje usporedba nelinearnog seizmičkog odgovora konstrukcija dimenzioniranih prema hrvatskim normama (HRP) i prema Eurokodu (EC8) koja je napravljena na modelima regularnih armiranobetonskih konstrukcija sa tri sustava za preuzimanje horizontalnih sila. Odabrano je više modela konstrukcija, a njihovi odgovori na djelovanje potresa izračunani su za pretpostavljeno djelovanje niza potresa. Globalni i lokalni parametri odgovora su analizirani i predloženi su odgovarajući zaključci.The nonlinear seismic response of structures dimensioned according to Croatian standards is compared with that of structures designed according to Eurocode 8. This comparison is based on models of regular reinforced-concrete structures with three systems for assuming horizontal forces. Several structural models have been selected and their seismic responses were calculated for the assumed impact of a series of earthquakes. Global and local seismic response parameters are analyzed and appropriate conclusions are proposed.L’article présente une comparaison de la réponse sismique non linéaire des constructions dimensionnées selon les normes croates et selon l’Eurocode 8, faite sur les modèles des constructions régulières en béton armé à trois systèmes de prise en charge des forces horizontales. On a choisi plusieurs modèles de constructions, tandis que leurs réponses à l’action sismique ont été calculées pour l’action supposée d’une série de séismes. Les paramètres globaux et locaux des réponses ont été analysés et commentés par des conclusions correspondantes.В работе показываèтся сравнение нелинейного сейсмического ответа конструкций расчитанных по Хорватским нормам и по Еврокоду 8, выполненное на моделях репулярных железобетонных конструкций с тремя системами для переноса горизонтальных сил. Выбрано большее число моделей конструкций, а их ответы на действие землетрясений расчитаны для предполагаемого действия ряда землетрясений. Глобальные и локальные параметры ответов анализированы, и предложены соответствующие заключения.Dargestellt ist ein Vergleich der unlinearen seismischen Erwiederung von Konstruktionen,k bemessen nach kroatischen Normen und nach Eurokode 8, ausgeführt an Modellen regulärer Stahlbetonkonstruktionen mit drei Systemen für die Übernahme von horizontalen Kräften. Es wurden mehrere Konstruktionsmodelle auserwählt, und deren Erwiederungen auf die Erdbebenwirkung für vorausgesetzte Einwirkung einer Reihe von Erdbeben berechnet. Globale und lokale Erwiederungsparameter sind analysiert und entsprechende Schlüsse vorgeschlagen

Single-frequency GPS positioning performance Around the time of the Chilean 2010 earthquake

Premda u ograničenim geoprostornim razmjerima, potresi su poznati izvori geomagnetskih i ionosferskih poremećaja. Kako navedeni poremećaji također utječu na značajke širenja radiovalova, može se očekivati utjecaj potresa na učinkovitost i kvalitetu rada satelitskih navigacijskih sustava. U radu su objavljeni rezultati analize kvalitete rada jednofrekvencijskih GPS prijemnika smještenih na odabranim položajima širom svijeta u vrijeme potresa koji je pogodio Čile 2010. godine. Analizirana je kvaliteta jednofrekvencijskog GPS pozicioniranja na odabranim referentnim stanicama u vremenskom intervalu neposredno nakon nastupa potresa. Također, ustanovljeno je vrijeme povrata funkcionalnosti GPS sustava u prvobitno operativno stanje. U istraživanju je vidljiv značajan kratkoročni poremećaj kvalitete rada GPS sustava na svim promatranim stanicama. U procesu sakupljanja podataka GPS opažanja umanjen je utjecaj raznih izvora pogrešaka u postupku određivanja položaja sustavom GPS, isključujući GPS ionosfersko kašnjenje i pomak u referentnom koordinatnom okviru. Teorijske analize pokazale su kako je utjecaj pomaka u referentnom koordinatnom sustavu zanemariv na učinkovitost GPS pozicioniranja; na ovaj način, ionosferski utjecaji izazvani potresom nastupaju kao najvjerojatniji uzrok degradacije kvalitete pozicioniranja jednofrekvencijskih GPS prijemnika širom svijeta.The earthquakes are known sources of geomagnetic and ionospheric disturbances, although on the restricted geospatial scale. Since such disturbances also affect the radio wave propagation characteristics, it is expected for the earthquakes to cause an impact on the satellite navigation systems’ performance. In this paper we have reported the results of the single-frequency GPS performance analysis at various locations around the globe at the time of the Chilean 2010 earthquake occurrence. The single-frequency GPS positioning performance at the selected reference sites in the time interval immediately following the Chilean 2010 earthquake outbreak has been analysed, and the GPS recovery time identified. Our study shows considerable short-term GPS performance disturbance observed at every location taken into consideration. The GPS observables collection process mitigates the impact of various GPS positioning error sources, excluding the GPS ionospheric delay and the reference frame shift. A theoretical analysis has shown negligible effects of the reference frame shift on the GPS positioning performance, leaving the ionospheric effects as the most probable cause of the earthquake-induced short-term single-frequency GPS performance degradation around the world

DIAGRAMME DER SEISMISCHEN WIDERSTANDSFÄHIGKEIT VON GEBÄUDEN DER DENKMALHINTERLASSENSCHAFT

Prikazan je način determinističke kvantifikacije pojma “seizmička otpornost” krutih zgrada s kamenim zidovima. Postupak se temelji na odnosu proračunskih i kapacitetnih vrijednosti parametara odziva konstrukcije. Pri proračunu su varirani parametri bitni za seizmičku otpornost zgrade. Rezultati provedenih proračuna sistematizirani su da bi se utvrdio međusobni odnos seizmičke otpornosti građevina s različitim stropnim konstrukcijama prema onima s “apsolutno krutim stropovima”.The deterministic quantification of the notion of "seismic resistance" of rigid buildings with stone walls is presented. The procedure is based on the relationship between the design and capacity values of structural response parameters. Parameters significant for seismic resistance of buildings were varied as appropriate in the course of the design process. The results of these calculations were systemized in order to determine the relationship between seismic resistance of buildings with different floor structures and those with "absolutely rigid floor structures".L’article présente le mode de quantification déterministe de la notion "résistance sismique" des bâtiments rigides aux murs en pierres. Le procédé se fonde sur le rapport entre les valeurs de calcul et les valeurs capacitaires des paramètres de la réponse de la construction. Lors du calcul on variait les paramètres essentiels à la résistance sismique du bâtiment. Les résultats des calculs ont été systématisés afin de déterminer le rapport entre la résistance sismique des bâtiments aux planchers variés et celle des bâtiments aux "planchers absolument rigides".В работе описан способ детерминистической квантификации понятия "сейсмическая устойчивость" жёстких зданий с каменными стенами. Способ основывается на отношении расчётных и численных мощностных значениях параметров ответа конструкции. При расчёте варьированные параметры были важными для сейсмической устойчивоcти здания. Результаты проведённых расчётов систематизированы с целью утвердить взаимное отношение сейсмической устойчивости сооружений с различными конструкциями перекрытий, по отношению к зданиям с "абсолютно жёсткими перекрытиями".Dargestellt ist die Weise der deterministischen Quantifizierung des Begriffs "seismische Widerstandsfähigkeit" starrer Gebäude mit Steinwänden. Das Verfahren ist begründet auf der Beziehung zwischen den Berechnungs- und Kapazitätswerten der Parameter des Konstruktionsrückhalls. Bei der Berechnung variierte man die Parameter die für die seismische Widerstandsfähigeit des Gebäudes wichtig sind. Die Ergebnisse der Berech-nung wurden systematisiert um die gegenseitige Beziehung der seismischen Wider-standsfähigkeit von Gebäuden mit verschiedenen Deckenkonstruktionen und solchen mit "absolut starren Decken" festzustellen

MODELLIERUNG ZWEISEITIGER ANSCHLÜSSE IN STAHLRAHMENKONSTRUKTIONEN

Kritički se komentiraju postupci modeliranja ponašanja dvostranih priključaka prema EN 1993-1-8, te se izlaže mogućnost metode konačnih elemenata kojom se u obzir uzima ponašanje priključaka na način da se standardni štapni model konstrukcije na dijelu priključka oko hrptenog panela stupa nadogradi ravninskim konačnim elementima. Na taj način se u obzir uzima stvarna geometrija priključka, nije potreban iteracijski postupak, a složenost modeliranja se prihvatljivo povećava.Performance modelling procedures for two-sided connections, based on EN 1993-1-8, are critically analyzed. Possibilities offered by the finite element method in the sphere of determining behaviour of connections, and this by adding in-plane finite elements to a standard structural model in the connection zone around the web panel of the pier, are determined. Thus the real geometry of connection is taken into account, the iterative procedure becomes unnecessary, and the modelling complexity is not significantly increased.La modélisation de comportement des connexions à deux faces, selon EN 1993-1-8, est analysée de point de vue critique. Les possibilités offertes par la méthode des éléments finis dans la détermination du comportement des connexions, et cela en introduisant les éléments plans finis dans le modèle standard structurel dans la zone de connexion autour de panneau d'âme de la pile, sont déterminées. De cette manière, la géométrie réelle de la connexion est prise en compte, la procédure itérative devient inutile, el la complexité de modélisation n'augmente pas de manière considérable.Приведены критические комментарии по процедурам моделирования поведения двухсторонних присоединений по EN 1993-1-8, изложена возможность применения метода конечных элементов, который учитывает поведение присоединений таким образом, что стандартная стержневая модель конструкции в области присоединения у хребтовой панели опоры достраивается плоскостными конечными элементами. Это позволяет учесть реальную геометрию присоединения, отпадает необходимость в выполнении итерационной процедуры, а усложнение моделирования является приемлемым.Die Verfahren der Modellierung des Verhaltens zweiseitiger Anschlüsse nach EN 1993-1-8 sind kritisch kommentiert. Ausgelegt ist die Möglichkeit der Methode der endlichen Elemente mi der man das Verhalten der Anschlüsse derweise in Betracht nimmt dass man das Standard-Stabmodell der Konstruktion am Teil des Anschlusses um das Stegpanel des Pfeilers mit ebenen endlichen Elementen anbaut. Auf diese Weise wird die tatsächliche Geometrie des Anschlusses berücksichtigt, ein iteratives Verfahren ist nicht nötig, und die Kompliziertheit des Modellierens ist annehmbar vergrössert

Teacher knowledge about dental injuries in young school-aged children

Zubna trauma nastaje iznenadno, a posljedice mogu biti vrlo ozbiljne i utjecati ne samo na zdravlje, nego i na psihološko i emocionalno stanje ozlijeđene osobe. Traume zuba kod djece najčešće su uzrokovane padovima ili udarcima u predmet koji je u blizini djeteta. Najčešće pogađaju djecu u dobi od druge do četvrte godine, a vrhunac zubnih ozljeda javlja se kod učenika mlađe školske dobi. Budući da djeca dosta vremena provode u vrtiću ili školi, vrlo je važno da odgojitelji i učitelji budu sposobni pravilno reagirati na zubnu ozljedu. Hitno i točno reagiranje važno je kako zbog sprječavanja straha i panike kod djeteta, tako i nastavka daljnjeg liječenja nastale traume. Svrha je ovoga istraživanja utvrditi razinu znanja učitelja o zubnim ozljedama učenika mlađe školske dobi. Rezultati ovoga istraživanja pokazuju kako je znanje o pravilnome postupanju učitelja kod zubne traume vrlo nisko te kako je vrlo malo učitelja dobilo informacije o tome. Iz dobivenih se rezultata može zaključiti kako je potrebno educirati i osposobiti učitelje za pravilno reagiranje u slučaju nastanka zubne ozljede.Dental trauma occurs suddenly and the consequences can be very serious. They affect not only health but also the psychological and emotional condition of the injured. Children dental trauma can be caused by falls or blows into an object near the child. The most commonly affected by dental injuries are the children aged from two to four and peak of dental injuries appears in younger school children. Since children spend much time in kindergarten or school, it is very important for educators and teachers to be able to respond properly to dental injuries. The urgent and accurate response is crucially important for preventing fear and panic as well as for further treatment of trauma. The purpose of this research is to check the level of teacher knowledge about the dental injuries in young school-aged children. The results of this research show that teacher knowledge about proper treatment in dental trauma is significantly low and very few teachers have received information about it. After analysing the results, it is concluded that it is necessary to educate and prepare teachers for the proper response in the situation of dental injury

INFLUENCE OF THE RESPONSE OF A SHALLOW FOUNDED REINFORCED CONCRETE FRAME STRUCTURE ON SOIL LIQUEFACTION POTENTIAL

Nakon katastrofalnih posljedica potresa na Aljasci i u Niigati 1964. godine, Seed i Idriss su razvili i objavili metodu za procjenu otpornosti tla na likvefakciju pod nazivom „pojednostavljeni postupak“. Dugo vremena se smatralo kako prisutnost građevine smanjuje opasnost od pojave likvefakcije, no nakon nedavnih potresa (Kobe 1995. i Kocaeli 1999.) uočeno je kako se likvefakcija pojavila ispod temelja građevina, iako nije došlo do njezinog pojavljivanja na slobodnim površinama tla u okolici građevina. U ovome radu analiziran je i uspoređen likvefakcijski potencijal tla neopterećenog objektom i tla ispod građevine, za dva profila relativno mekog tla u Osijeku pri djelovanju dva potresa različitog frekventnog karaktera i magnitude. Linearno-elastične analize vremenskim zapisom provedene su koristeći računalni program SAP2000 za slučaj neopterećen objektom i za slučaj prisutnosti i utjecaja odziva plitko temeljene armiranobetonske okvirne konstrukcije. Dodatno su prikazani i osnovni dinamički odzivi same konstrukcije u interakciji s tlom, te je dana kratka usporedba s općeprihvaćenim modeliranjem apsolutno krutih oslonaca konstrukcije.Following disastrous earthquakes in Alaska and in Niigata in 1964, Seed and Idriss developed and published a method for evaluating liquefaction resistance of soils termed the ‘‘simplified procedure’’. For a long time it has been considered that the presence of the building reduces the risk of liquefaction, but after the recent earthquakes (Kobe 1995. and Kocaeli 1999.) it was observed that the liquefaction occurred under the foundations of buildings, although it has not been observed in the free field around buildings. This paper analyzes and compares soil liquefaction potential in the free field and beneath the building, for two relatively soft soil profiles under the influence of two strong motions with different frequency character and magnitude. A linear-elastic time history analysis was conducted using computer program SAP2000 for the free field case and case with presence and response impact of a shallow founded reinforced concrete frame structure. In addition, basic dynamic response of the structure in interaction with the soil is presented and a short comparison is made opposite to the widely accepted rigid-base structure assumption

PRELIMINARY DESIGN OF CABLE-STAYED FOOTBRIDGE

Rad prikazuje idejno rješenje pješačkog mosta preko rijeke Drave u Osijeku. Širina vodene prepreke koju je potrebno premostiti iznosi 195,0 m. Odabrano rješenje je ovješeni armiranobetonski most s jednim ekscentričnim kosim pilonom. Grafički prikaz mosta je izrađen u programskom paketu AutoCad, a numerički model mosta u programskom paketu SAP2000 v14.2. Na osnovi odabranih izmjera pojedinih dijelova konstrukcije, analize promjenjivog opterećenja prema EN1991-2 te odgovarajućih kombinacija opterećenja (EN1990), izvršena je modalna analiza i proračun odgovarajućih reznih sila mosta.This paper presents a preliminary design of a footbridge over the River Drava in Osijek. Width of the water obstacle is 195,0 m. The selected solution is cable-stayed reinforced concrete bridge with an eccentric inclined pylon. Graphical drawings of the bridge were made in AutoCad software package and numerical model in the SAP2000 v14.2 software package. Modal analysis and calculation of the section forces was performed on the basis of selected dimensions of certain parts of the bridge structure, the analysis of variable loads according to EN1991-2 and the appropriate combination of loads according to EN1990