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Hrvati iz Bosne i Hercegovine zastupljeni su u zakonodavnoj vlasti Republike Hrvatske od 1995. godine kada je omogućen direktan ulazak u parlament hrvatske dijaspore u posebnoj izbornoj jedinici temeljem pozitivne diskriminacije. Parlamentarni izbori provedeni su prema tim pravilima 1995. godine, zatim 2000., 2003, 2008., 2011, 2015., te 2016. godine. Osim u zakonodavnoj vlasti predstavnici Hrvata iz dijaspore bili su imenovani na razne pozicije u izvršnoj vlasti, a do 2000 godine i u Uredu predsjednika Franje Tuđmana koji je u polupredsjedničkom sustavu imao važnu ulogu imenovanja pojedinaca na razne pozicije u vlasti Republike Hrvatske.

Space 3D structures with constant geometry and material properties in the third direction are often encountered in the engineering practice so that they deserve a more complex approach than the usual procedures employed to deduce to different submodels like beams, walls, plates and shells. Here is presented the threedimensional state of the mentioned structures as a combination of states in a transversal plane and in the third coordinate direction. A cross section was discretisated on twodimensional finite elements and the third coordinate direction was solved analytically with the aplication of the members of trigonometric polynomials in accordance with the rules of Fourier's analysis. Although it is linear problem, this concept is based on the analogy with the analysis of nonlinear problems so that the analysis is derived with the given accuracy with respect to the third coordinate direction. Namely, all relevant values on the third direction are developed into Fourier's series, so that these values can be computed with the given accuracy. The efficiency of the developed numerical model used for the analysis of space threedimensional structures with constant properties in the third direction has been confirmed in solving actual characteristic examples of engineering structures.

This paper presents a mesh free method for solving the torsion problem of prismatic bars. This method applies Fup basis functions, which belong to the class of Rvachev’ s infinitely derivable finite functions. As it is possible to calculate derivation values of Fup basis functions of high degree in a precise yet simple way, so it is possible efficiently to apply strong formulation procedures. The proposed method represents the problem domain and its boundaries by a set of nodes rather than resorting to the traditional discretization into finite elements. The collocation method was used to form a system of equations in which the differential equation of the problem is satisfied in collocation points of closed domain, while boundary conditions are satisfied exactly at the domain boundary. The proposed mesh free method offers a multilevel approach that achieves the approximate solution of an arbitrary accuracy by hierarchically increasing the number of basis functions in the domain. Values of the main solution function and all the values derived from the main solution are calculated in same points since numerical integration is avoided. Numerical model is illustrated by examples of linear and elasto-plastic analyses of prismatic bars subjected to torsion. The propagation of plastic zones in the cross-section is monitored by applying the incremental iterative procedure until its failure.

Tradicionalni građevinski objekti na području Blidinja i šire okolice u drugoj polovici XIX. i prvoj polovici XX. stoljeća imali su određena identitetska obilježja područja kao i obilježja graditeljstva toga vremena sa svim svojim specifičnostima. Dat je osvrt na samo jedan segment toga graditeljstva sa specifičnim arhitektonsko konstrukcijskim odlikama. Naznačene odlike ovise o rasponima pojedinih konstrukcija, o umijeću tadašnjih graditelja, odnosno o raspoloživosti odgovarajućih tradicionalnih materijala i jednostavnih graditeljskih alata. Da bi se izgradile kuće, pojate, čatrnje i druge karakteristične građevine i da bi se premostili i svladali u pojedinim slučajevima kritičniji konstrukcijski rasponi za to doba uglavnom su se koristili osnovni materijali kao drvo, kamen vapnenac, vapneni mort, crvenica, a katkada i čelični klinovi i šipke. Za pokrove su se koristili materijali poput slame, raži i drugih žitarica, trske, kamenih ploča, daščica i samonikle vegetacije. Članak se ograničava samo na načine gradnje onih najzahtjevnijih i najspecifičnijih građevina i detalja na njima promatranih s konstrukcijskog stajališta kao jedan prilog možebitnoj sveobuhvatnoj budućoj analizi graditeljstva toga doba.

U ovom radu predstavljen je algoritam za numeričku analizu prostornih 3D konstrukcija s pravilnim geometrijskim i materijalnim svojstvima u jednom smjeru. Takve se konstrukcije često susreću u inženjerskoj praksi, tako da samim tim zaslužuju i cjelovitiji pristup od do sada uobičajenih postupaka svođenja na podmodele tipa grede, zida, ploče ili ljuske. Ovdje je prostorno trodimenzionalno stanje naznačenih konstrukcija prikazano kao kombinacija stanja u poprečnoj ravnini i trećem koordinatnom smjeru. Najprije su analizirani uobičajeni postupci i metode svođenja stvarnog prostornog stanja na dvodimenzionalne konstrukcije različitih tipova. Zatim su analizirane prostorne 3D konstrukcije bez uvođenja podmodela, što i jest cilj ovog rada. Izvršena je diskretizacija poprečnog presjeka na dvodimenzionalne konačne elemente, a treći je koordinatni smjer rješavan analitički uporabom članova trigonometrijskih polinoma po pravilima Fourierove analize. Funkcionalnost kreiranog numeričkog modela za analizu prostornih 3D konstrukcija s pravilnim svojstvima u jednom smjeru potvrđena je na rješavanju karakterističnih primjera inženjerskih konstrukcija.

Suvremeni pristup u numeričkom modeliranju složenih inženjerskih konstrukcija predstavlja simuliranje ponašanja istovremeno cijele konstrukcije. U okviru analize konstrukcija sastavljenih od ljuski i stupova, javljaju se specifični problemi povezivanja različitih konačnih elemenata u kompatibilnu cjelinu. Svi dostupni algoritmi za analizu ljuskastih konstrukcija zasnovani su na konačnim elementima ljuske koji imaju po pet stupnjeva slobode u svakom čvoru, što postaje prepreka u njihovom povezivanju s grednim konačnim elementima. Ovdje je razvijen cjelovit i efikasan algoritam za numeričko modeliranje konstrukcija sastavljenih od ljuski i stupova (grednih elemenata). Osnovni problem, koji se odnosi na nekompatibilnost pomaka točnije zaokreta u čvoru koji je zajednički za konačni element ljuske i gredni element, riješen je uvođenjem konačne rotacijske krutosti ljuske oko normale na njezinu srednju plohu. Time je formuliran izoparametrijski element ljuske sa šest stupnjeva slobode u svakom čvoru koji se, osim što zadovoljava uvjete kompatibilnosti u spojevima pojedinih elemenata konstrukcije, također pokazao i pogodan za modeliranje naboranih ljuskastih konstrukcija. Drugu važnu cjelinu u razvoju numeričkog modela čini implementacija numeričke interpretacije grednog elementa u osnovni model za analizu ljuskastih konstrukcija. Na osnovu postojećih saznanja što se tiče različitih formulacija rotacijskog stupnja slobode oko normale na srednju plohu ljuske, pronađeno je originalno rješenje. Funkcionalnost kreiranog numeričkog modela za analizu konstrukcija sastavljenih od ljuski i grednih elemenata potvrđena je na primjerima specijalnih inženjerskih konstrukcija.

We present an adaptive method for numerical solving boundary-initial value problems. To solve 1D initial boundary value problem, we convert the problem into 2D problem. This boundary value problem is then solved by using infinitely differentiable basis functions with compact support called Fup basis functions and the collocation technique. Partial differential equations are solved simultaneously in the space- time domain with resolved all space and time multiple scales. The proposed method is generally meshless method because it requires only adding of collocation points and basis functions over the domain, not the classic domain discretization and the numerical integration. Numerical adaptive algorithm adds new collocation points in the next resolution level only in the space-time zones where solution correction is greater than the prescribed threshold. With this approach, the Fup coefficients measure the local fluctuation of the solution simultaneously in space and time.

U ovom članku je prikazan algoritam za numeričku analizu prostornih 3D konstrukcija s pravilnim geometrijskim i materijalnim svojstvima u jednom smjeru. Za takve konstrukcije se prostorno trodimenzionalno stanje prikazuje kao kombinacija stanja u poprečnoj ravnini i trećem koordinatnom smjeru. Najprije su analizirani uobičajeni postupci i metode svođenja stvarnog prostornog stanja na dvodimenzionalne konstrukcije različitih tipova. Zatim su analizirane prostorne 3D konstrukcije bez uvođenja podmodela što je osnovna ideja ovog rada. Izvršena je diskretizacija poprečnog presjeka na dvodimenzionalne konačne elemente, a treći je koordinatni smjer rješavan analitički uporabom članova trigonometrijskih polinoma po pravilima Fourierove analize. Funkcionalnost kreiranog numeričkog modela za analizu prostornih 3D konstrukcija s pravilnim svojstvima u jednom smjeru potvrđena je na rješavanju karakterističnih primjera inženjerskih konstrukcija.

U okviru analize konstrukcija sastavljenih od ljuski i stupova, javljaju se specifični problemi povezivanja različitih konačnih elemenata u kompatibilnu cjelinu. Svi dostupni algoritmi za analizu ljuskastih konstrukcija zasnovani su na konačnim elementima ljuske koji imaju po pet stupnjeva slobode u svakom čvoru, što postaje prepreka u njihovom povezivanju s grednim konačnim elementima. Ovdje je razvijen cjelovit i efikasan algoritam za numeričko modeliranje konstrukcija sastavljenih od ljuski i stupova (grednih elemenata). Osnovni problem, koji se odnosi na nekompatibilnost pomaka točnije zaokreta u čvoru koji je zajednički za konačni element ljuske i gredni element, riješen je uvođenjem konačne rotacijske krutosti ljuske oko normale na njezinu srednju plohu. Time je formuliran izoparametrijski element ljuske sa šest stupnjeva slobode u svakom čvoru koji se, osim što zadovoljava uvjete kompatibilnosti u spojevima pojedinih elemenata konstrukcije, također pokazao i pogodan za modeliranje naboranih ljuskastih konstrukcija. Drugu važnu cjelinu u razvoju numeričkog modela čini implementacija numeričke interpretacije grednog elementa u osnovni model za analizu ljuskastih konstrukcija. Na osnovi postojećih saznanja, što se tiče različitih formulacija rotacijskog stupnja slobode oko normale na srednju plohu ljuske, iznašlo se originalno rješenje.

U ovome radu

Problematika rada proizašla je iz promišljanja autora o tome koliko je povratak Hrvata u Bosansku Posavinu stvarno moguć kao i o tome postoje li pretpostavke za povratak. Radom se želi naglasiti važnost ulaska Bosne i Hercegovine u Europsku uniju. Bosna i Hercegovina je u svojoj dosadašnjoj interakciji s Europskom unijom pokazala da je put prema Europskoj uniji strateško opredjeljenje države i da se ulažu kontinuirani napori kako bi se taj cilj ostvario. Integracijom Bosne i Hercegovine u Europsku uniju otvaraju se nove perspektive za razvoj Bosanske Posavine, ali i za povratak Hrvata na to područje. Rad se sastoji od pet dijelova, a glavni cilj rada je prikazati koristi koje ulazak Bosne i Hercegovine donosi Bosanskoj Posavini. Također, rad može poslužiti kao temelj za daljnja istraživanja problematike povratka Hrvata u Bosansku Posavinu posebno s aspekta ispitivanja očekivanja koje potencijalni povratnici imaju od područja Bosanske Posavine.

Autor u radu prikazuje državno-pravni položaj Bosne i Hercegovine u pravaškim političkim koncepcijama. Pravaštvo je u modernoj hrvatskoj povijesti 19. i 20. stoljeća bilo jedna od relevantnih nacionalno-integracijskih i političkih ideologija. Kroz slučajeve pravaških stranaka tijekom razdoblja Habsburške / Austro- Ugarske Monarhije, zatim Kraljevine Srba, Hrvata i Slovenaca / Jugoslavije i u konačnici Republike Hrvatske autor prikazuje kakav je bio položaj Bosne i Hercegovine u pravaškim političko-programatskim koncepcijama. Ukazujući na osnovne značajke pravaštva, autor zastupa tezu da je pitanje Bosne i Hercegovine pravaštvu u hrvatskoj stranačko-političkoj povijesti zauzimalo posebno važno mjesto. Stoga je u fokusu ovog rada isključivo pravaško viđenje Bosne i Hercegovine koje ima svoj značaj za potpunije upoznavanje događaja na široj javnoj sceni.

Povijest, kultura i jezik, europski put i demokratizacija, ustavna i institucionalna jednakopravnost, europska BIH i svaki drugi oblik političke, društvene, prostorne i ine organizacije apsolutno nemaju nikakvog smisla u uvjetima demografskog nestanka Hrvata u BIH. Razina demografske destrukcije Hrvata u Hrvatskoj i u BIH je tolikih razmjera da nam svaka druga djelatnost nema gotovo nikakvo značenje nastave li se recentni trendovi depopulacije, prirodnog pada, izumiranja i iseljavanja. Problem ne možemo prikriti nikakvim objašnjenjima niti fiktivnim slaganjima stanovništva i njegove strukture u službenim popisima, ali ga konačno možemo sagledati, razumjeti i početi rješavati. Ne krenemo li odmah vrlo nam jednostavna matematička ekstrapolacija navješćuje, uz postojeći prirodni pad i vanjsku negativnu migracijsku bilancu (dakle, bez ubrzavanja procesa uvjetovanih starenjem ukupne populacije i silinom iseljavanja mladog i obrazovanog stanovništva), smanjenje ukupne hrvatske populacije u BIH za slijedećih 10 godina sa sadašnjih oko 400 000 na vrlo vjerojatno manje od 300 000 osoba. Možemo samo pretpostaviti ukupnu starost te populacije (vjerojatno blizu 50 godina), odnose mladog i starog stanovništva (najmanje dvostruko više starijih od 60 (65) godina nego mladih mlađih od 19 godina, smanjenje rodnosti (vjerojatno ispod 3 000 rođenih), povećanje smrtnosti (vjerojatno preko 7 000 umrlih), intenziviranje prirodnog pada (vjerojatno preko 3 000 osoba), izumiranje (najgori tip E4 općeg kretanja stanovništva), moguću supstituciju stanovništva (kroz velike migracije prema Europi), itd. itd. Pretpostavke o ukupno oko 300 000 Hrvata u BIH uz takve su procese zapravo vrlo optimistične i gotovo bismo mogli reći nerealne. Hoćemo li konačno shvatiti kako se radi o povijesnom odlasku Hrvata nakon kojeg povratka više nema. I sve to u uvjetima velikog migracijskog pritiska prema Europi iz jugozapadne Azije i sjeverne Afrike. Kad problem prihvatimo kao hrvatski politički i svaki drugi prioritet moguće ga je početi i rješavati na ukupnom hrvatskom demografskom i svakom drugom potencijalu u BIH, Hrvatskoj i klasičnom hrvatskom iseljeništvu.

Autor u radu analizira i rekonstruira djelovanje Hrvatske stranke prava u Bosni i Hercegovini od 1990. do 1999.godine. Glavni politički program i cilj stranke bio je uspostava nezavisne hrvatske države na cjelokupnom povijesnom i etničkom prostoru. Takav politički program obuhvaćao je cijeli državni teritorij Bosne i Hercegovine koji bi se temeljio na ujedinjenju Republike Hrvatske i Republike Bosne i Hercegovine putem referenduma u jednu državu. Tijekom rata u Bosni i Hercegovini, stranka se zalagala za državnu cjelovitost, te je organiziranjem Hrvatskih obrambenih snaga sudjelovala u njezinoj obrani.

Jedna od temeljnih razlikovnih značajki Hrvata u odnosu na Srbe, Bošnjake, Crnogorce jest u njihovoj esencijalnoj pripadnosti zapadno-europskom kulturnom krugu. Dakle krugu koji je formirao i samu Europsku Uniju te koji presudno utječe na profilaciju njenih vrijednosti. Obzirom na to bilo bi očekivano da i Hrvati u BiH najagilnije djeluju na etabliranju tih vrijednosti. Međutim, u BiH je osnovni problem vezan uz regulaciju nacionalnih statusa i odnosa. U razrješenju tog problema europski vrijednosni sustav može biti samo dijelom spektra najrazličitijih utjecaja iz čijeg se međudjelovanja oblikuje bosansko-hercegovačka politička zbilja. Stoga su za afirmaciju hrvatskih pozicija i interesa presudne spoznaje o ukupnosti tog spektra kao i sposobnost prilagođavanja dinamici kojom je određen. Sukladno tome, zasigurno da postoje okolnosti u kojima je potrebno istaknuti, nazovimo zapadnjački segment hrvatskog identiteta ali i takve gdje je primjerenije ukazati na stoljetnu hrvatsku otvorenost prema kulturama i civilizacijama koje su usporedno sa Zapadom doprinosile oplemenjivanju svijeta.

A numerical model based on exact arch finite elements with six degrees of freedom for structural analysis of arched girders is presented in this paper. This finite element is exact in the sense that it gives the exact result for a mesh of arbitrary density in the arch of constant curvature loaded in nodes. Introducing deformation characteristics and characteristics of materials into the system of three differential equations of equilibrium of the second order for the arch element, the differential formulation of arched girder is obtained. Each node unit displacement is associated with three basis functions, resulting in 18 algebraic-trigonometric basis functions in one finite element. Based on thus obtained basis functions, the field of displacements (deformations) is described, and by the minimization of potential energy functionals, the exact stiffness matrix of girder element of constant curvature is derived. By using stiffness matrix obtained in this way, it is possible to completely eliminate shear and membrane locking effects in the arch element. In that, the joint influence of bending, shear and contribution of longitudinal forces is included. Examples of arch structures in a plane were analyzed using the created numerical model for characteristic cases of loading and different support conditions.

The paper briefly described numerical model for submerged structures under seismic load condition. The applied material model’ s primary purpose is the simulation of fluidstructure interaction in seismic conditions. It includes the most important nonlinear effects of fluid and structure. Some model's possibilities are illustrated on seismic behavior of underwater oil tank of "Khazzan" type.

In this paper the plastification of the reinforced concrete (RC) frames are analyzed by numerical model [1, 2] which includes material and geometric nonlinearity according to small displacement theory. The global iterative-incremental procedure is used with a monotonic increase of loading until collapse of system which is caused by occurring of mechanism and/or losing of stability. The composite cross sections are described by numerical model. For analysis of space frames, the torsional effect and consequently the effect of the shear force of the reinforced concrete element are observed on the so-called comparative body. It is formed so that the square elements from the cross-section discretization are extended along the whole linear finite element and form an elastic body discretized by 3D brick finite elements (Figure Ib). The essential properties of results with plastification of RC frames are changes of position of plastic hinges. After the first appearance, during increment procedure, plastic hinge can disappear and appear again. The complete process of plastic hinge appearance is non-continuous. The dominant order of the plastic hinge appearance i.e. the dominant failure mechanism is only what can be determined.

This paper presents a possible application of materially and geometrically nonlinear models on nonlinear static analysis of spatial frames according to EN EUROCODE 8. The main assumptions of a developed model are described in brief. The model very accurately constructs the equilibrium curve (pushover curve) as the basis for application of the static nonlinear analysis of seismic effect. In a simplified way, this paper presents the application of the method of target displacement as the basis for the method of bearing capacity and then also the method of bearing capacity itself. Cases of uniform and modal types of seismic loads were elaborated through examples. Attention was paid to values of displacements of the original mathematical model and their comparison with target displacements defined according to EN ECS. This model analyzed: (1) RC frames of various types and numbers of stories, (2) flexural walls, free-standing and connected with panels, and (3) walls with openings. The conclusion presents engineer's comment on the structural bearing of specific RC systems, with emphasis on the extent of expected deformations.

This paper briefly presents numerical model for the nonlinear analysis of spatial concrete framework systems. The model is based on the linear-elastic bar model and the model for dimensioning of general composite cross sections loaded with excentric axial force. The model of material behaviour can be set arbitrarily according to the experiment or the relevant standards.

Masonry-infilled frames are composite systems consisting of frames made either of steel or concrete, and the infill usually of bricks. While it is obvious that infill increases the stiffness of the frame structure under working loads its behavior under extreme loads is unknown and therefore treated with caution. The analytical model used in the design process should directly incorporate the infills, rather than being based on the analysis of the bare frame with essentially empirical corrections (magnification) of the design actions, as suggested in Eurocode EN 1998-1. The only feasible way to account for the negative effects of irregularly arranged infill walls, but also for the positive effects of the infill which act effectively as a ‘ first line of defense’ in the structure, is to directly include the infill walls in the analytical model used for design. Rehabilitation of buildings to improve the seismic behavior is being widely used all around the world. Infilling of the frames with panels presents a viable perspective. Simplified design methods, that reliably represent the behavior of structures with infill, are necessary for enabling parametric analysis in the design phase as well as fast evaluation of the existing structures. In this article we tried out the possibilities of linear model for infill to simulate the nonlinear behavior of infilled-frame systems on a model structure. That is also a first step towards improving and making the seismic modeling of infill frames simpler.

This paper presents the Adaptive Fup Collocation Method (AFCM) for 1D numerical solving of the problem of bending of a continuous girder on an elastic base. The method is based on the collocation procedure by using Fup basis functions that belong to the class of atomic basis functions. Because of the localization of basis functions, the method develops load, solution and all their derivatives in a multiresolutional way representing all necessary frequencies. Girder is modeled using elastoplastic material, and the nonlinearity in the contact of girder and base is taken into account. Results show that the accuracy of the numerical solution is determined by the selected deviation by which the method accuracy and its analytical characteristics are presented. The solution is described by the adaptive position of collocation points (adaptive grid) that, in addition to presenting significant frequencies and spatial scales, provides minimum spatial discretization and efficiency of the numerical procedure. A large number of collocation points are necessary only in zones of concentrated forces, plasticization, bearings or high displacement gradients and its derivatives.

The paper briefly presents experimental tests for omnia slabs and comparison with results of numerical model. Six types of reinforced concrete (omnia) slabs with various types of connection constraints were tested, while deflections in the middle of the span, under different level of load are measured. The achieved test results were compared with the results obtained through the developed numerical model and are evident very good accordance between developed algorithm and test results.

The reservoir routing problem describes relationship between incoming and outcoming quantity of water when there is retention of certain volume present in the flow. The problem has been recognized and dealt with for quite some time but this paper offers new insights by presenting the problem in sound mathematical formulation based only on the mass conservation principle. Application of the mass conservation principle enables all formulations to be presented: integral and differential formulations based on either the water content or on the water level in the reservoir. During the solution process some new functions with clear physical meaning have been introduced in order to facilitate the solution procedure. It becomes evident that some formulations are more advantageous in terms of stability or simplicity. Calculations in the examples are based on real data from the artificial water accumulation Botonega in Croatia.

In this work presented are the new testing methods and so determined mechanical properties of the masonry bricks and mortar produced and used in Croatia for regular masonry buildings. Testing methods and procedures are as specified in Eurocode 6: Design of masonry structures (1 and 2) and relevant European standards. According to EC6 and EC8, only the use of dimensioned masonry units is allowed for the construction of masonry buildings. Requirements regarding materials and manufacture, dimensions and tolerances, density mechanical strength, water absorption, frost resistance, soluble salt content, etc. are specified for each type of masonry unit. The experimental methods and results of the preformed tests are presented for three different brick elements commonly used in Croatia: perforated fired clay block, perforated concrete block and aerated-autoclaved concrete blocks. Mortar used for binding the blocks together was general purpose mixed cement-lime mortar M5. For verification of the load bearing capacity of masonry walls and structures for vertical and lateral loads, the values of mechanical properties of masonry considered as an assemblage of masonry units and mortar, and not mechanical properties of constituent materials are used. Tests outlined and performed are the typical ones for determination of the brick group, compressive strength of a brick, shear strength of the wall segments, compressive strength of wall segments and modulus of elasticity of the wall segment. They represent the main input data for any further analysis of the masonry buildings and they could be used as good reference for designers, brick industry and masonry builders in Croatia.

The Old Bridge in Mostar was constructed in 1566 and destroyed on 9 November 1993 under still insufficiently clarified circumstances. The preparation for the reconstruction lasted for several years, and finally the realization of the restoration project was taken up in 2002. The reconstruction of the bridge and other structures on the site was completed in the first half of 2004. By the opening ceremony on 23 June 2004, the Old Bridge was again in its function. It was constructed of the very same types of materials as the original bridge. Also, the method of workmanship and fitting of individual components corresponds to the original state as much as it was possible to achieve. Some minor differences that inevitably exist, given the long time interval, will be emphasized and analyzed in this paper. It is important to stress that some important data and facts, which were unavailable before the reconstruction and which were subject to speculations for various reasons in the past, are presented here for the first time.

The spectral element method has advantage compared to other numerical methods in possibility to describe the structural model with minimum number of elements, and in dynamic analysis in frequency domain which enables taking into account foundation soil influence through impedance functions. Scope of the research is theory and application of spectral elements to frame structures, also deep beams, considering soil- structure interaction effects. Special attention is dedicated to the spectral elements based on Timoshenko’ s beam theory, which means that shear deformation is taken into account in vibration analysis. Special program in Matlab v.7.0.1. has been developed to calculate structural response on earthquake load, traffic load (Rayleigh waves) and other types of dynamical excitations in domain of mathematical model of structure (wind, machines, explosions) an outside. Objective is to obtain results of high accuracy in dynamic loading influence estimation on structure founded on soil of various characteristics.

Reinforced-concrete infilled frames are composite structures whose behavior under horizontal loads is difficult to predict. The evaluation of the infill effect is very difficult because stiffness and strength are conditioned by complex phenomena of interaction occurring at the frame-infill interface. These phenomena depend on numerous variables like mechanical properties of infill (masonry and mortar characteristics) and of frame members, details of frame members, frame-infill stiffness ratio and even vertical load transferred from the frame to the infill. In order to solve this problem we tested the applicability of neural networks, trained on the compiled experimental database, for prediction of the seismic behavior of infilled frames. An experimental database includes data from laboratory tests carried out on one story, one bay r/c frames infilled with unreinforced masonry. The inputs of the neural networks are geometrical and material properties of the frame, infill and loading. Output variables are deformation capacity in terms of drift, shear strength and mode of failure of infilled frames. The obtained results could be used for quantitative prediction of infilled frame behavior expressed in terms of shear strength and deformation capacity which is of vital importance for performance based design of the new buildings and evaluation of the existing ones.

This paper presents an analysis of the seismic loading of structures based on combined windows-wavelet transformation of ground accelerations which separates an acceleration function into harmonic waves of different periods and shows the intensity of each wave in an accelerogram. The function which represents the maximum intensity of acceleration for the observed wave in an accelerogram is named the resonant spectrum input. The response of the single degree of freedom system subjected to resonant spectrum input gives resonant response spectrum. The resonant response spectrum displays a similar behaviour as the classical acceleration spectrum, but with some specific behaviour, depending on a number of terms of the fluctuating component. In the case when the greater number of the fluctuating term is taken, the resonant acceleration spectrum gives more unfavourable response of the single degree of freedom system for the observed earthquake accelerogram with respect to the classical spectrum.

Behavior of bridges in transversal direction is very difficult to foresee because of the large number of parameters which influences them. Ratio between stiffness of the piers and bridge deck is one of the most important parameters of the bridge response. If the piers are relatively high and slender the response of the bridge is dictated with deck stiffness. Then it is important to determine the exact ratio of the stiffness when the piers do not disturb the response. One method uses wave equation to determine the behavior of structure and another uses finite elements. It is impossible to solve all construction static systems with wave equation but only simple ones and it has a shortfall that it can determine only first few accurate modal shapes. Although less accurate, with the FEM it is possible to determine larger number of modal shapes. In this paper example of continuous bridge will be analyzed using both methods.

In the present paper a current status of development of a 3D numerical chemo-hygro-thermo-mechanical model for concrete is presented. In the model the interaction between the non-mechanical (distribution of temperature, humidity, oxygen and chloride) and mechanical properties of concrete (damage) is accounted for. The strong and weak formulation of the model and its implementation into a 3D finite element code are discussed. The formulation is restricted to the processes up to the depassivation of reinforcement. The application of the model is illustrated on one numerical example in which the transient 3D FE analysis of RC slab is carried out in order to investigate the influence of damage of concrete on the depassivation time of reinforcement. In the analysis the load free and previously loaded RC slabs are exposed to the aggressive influence of sea water. Due to external load, the loaded beam was damaged before the exposure of sea water. Consequently, its depassivation time is shorter than the depassivation time of companion beam which was load free. The reason is due to the cracking of concrete, which significantly accelerate processes that are relevant for depassivation of reinforcement. The numerical results are in good agreement with the observation from the engineering practice.

In the present paper the three-dimensional finite element code, which is developed to study the penetration of a steel anchor into a concrete block, is briefly described. The contact between the anchor, which was assumed to be linear elastic, and the concrete, was solved using the penalty method. The friction between master body (concrete block) and slave body (anchor) is of kinematical type and could be described with the Mohr- Coulomb friction law. At the present stage of computer code development no friction is taken into account. As a constitutive law for concrete, the rate dependent microplane model will be employed (co-rotational formulation). Since in the code the re- meshing strategy had to be used, the mapping of damage variables will be performed by interpolation of their nodal values. It is demonstrated that the solution of the contact problem heavily depends on the finite element discretization of the model.

This paper is based on following hypothesis: Seismic response analysis of regular structure is quite correct if it is done as simplified non-liner analysis with time history function of ground motion, as input load, and SDOF model with known weight, elastic stiffness, damping, elastic base shear capacity and post-elastic stiffness, representing the structure. Weight of structure is known, elastic stiffness can be defined by static push analysis and dumping can be assumed depending of type of structure (5% for RC structures). Most important step in described approach is definition of elastic base shear capacity and post-elastic stiffness. Both parameters depend of failure mechanism and potentional of non-linear deformation absorption capacity. Three cases are described in paper: Regular structure with RC walls tested by Camus working group named as Camus3 experiment (July 2000), Regular RC frame and RC grider bridge in longitudinal direction. Good conformity of the Camus 3 experiment results with numeric simulation, as well as comparators of results given by space model and SDOF model in the other two cases, shows that such simplified seismic analysis is quite acceptable. Procedure is rather quick and easy with extremely simplified structure modelling. Results shows that seismic response of regular structures (symmetric plans and constant vertical stiffness) can be well interpreted by using SDOF system as a mathematical model of the structures. In cases when ductile failure mechanism (plastic hinge, plastic rotation) is possible this approach can be used. That condition has to be check by preliminary steps. Aim of all preliminary steps is to confirm obligatory condition and to find out working diagram envelope of SDOF system representing real structure. Good confirmations of results shows that simplified seismic analysis is quite acceptable for regular structures in engineering practice.

This paper presents the elastic response spectra of a single-degree-of-freedom system (SDOF), which is obtained from the measured data of the force caused by a wind named Bora. All the data of the wind force are obtained by measurements on a SDOF oscillator. The time resolution varies from 0.01 to 0.00001 second. The spectra are constructed for different intensities of the dynamic wind force, i.e., for a wind with different average velocities. After presenting the spectra in a non-dimensional form, their reciprocal similarity can be observed irrespective of the intensity of the wind force. It can be observed from the presented results that the ordinate of elastic response spectra increases with decreasing natural period of the SDOF. The paper also presents a practical method for determining the elastic response spectrum for a particular SDOF and a newly specified location, based on the known data of the average wind velocity.

The paper presents a three-dimensional numerical model for describing nonlinear behaviour of prestressed concrete structures. The nonlinear behaviour of concrete is described by an elastoplastic material model which is based on the Mohr-Coulomb law for dominant compression stresses and the Rankine law for dominant tensile stresses. A multisurface presentation of the model is implemented which permits the rapid convergence of the mathematical procedure. Nonlinear triaxial behaviour of concrete is involved in the model, including all dominant influences in concrete: yielding in compression, cracking in tension, softening and hardening. The model is defined by elementary material parameters (Young’ s modulus, Poisson’ s coefficient, maximal uniaxial tensile and compression stresses, coefficient of tensile correction, maximal tensile and maximal compression strains) so that the very complex behaviour of prestressed concrete structures can be described simply and effectively but with a sufficiently accurate model. The nonlinear behaviour of prestressed tendons is described by the one dimensional elasto-viscoplastic model. The tendon element geometry is described by the second order space function which is determined by its projections. These elements make it possible to model arbitrarily curved prestressing tendons in space, thus they can be determined independently of the 3D finite element concrete mesh. This is very important in the case when the prestressing tendon can not be located in one plane. The transfer of prestressing force on the concrete is modelled numerically. Among the losses which influence the decrease in the prestressing force it is possible to compute the losses caused by friction and the losses which result from the concrete deformation. The developed model makes it possible to compute prestressing structures in phases: before prestressing, during prestressing and after prestressing. The described models for concrete and reinforcement are implemented in the computer programme for a 3D analysis of the prestressed concrete structures where the structures are discretized by three-dimensional finite elements with an embedded one-dimensional element of prestressed tendons. The programme is tested on a few examples and the obtained results are compared with the known numerical and experimental ones.

Contrary to the prenorm ENV 1993-1-1:2002/A2:2008 the final version of the European norm for the design of steel structures EN 1993-1-1:2005 does not afford special attention to castellated beams. Therefore, engineers should determine the resistance of castellated beams by application of the finite element method (§ 6.3.4.). Furthermore, determining the lateral-torsional buckling resistance of castellated beams is more complicated because appropriate buckling curves are not assigned in this norm. The non-linear modelling of castellated beams in bending according to recommendations given in EN 1993-1-1:2005 is shown in this paper. Moreover, while modelling this structural element geometrical and material non-linearity are taken into account. 3D models of beams are used and the design resistance to lateral-torsional buckling is determined by computer programme NISA II/DISPLAY. The cross-section, span and restraint conditions of the castellated beam matched the tested castellated beam in the laboratory.

Knowledge about protected management categories or models is basic for finding an optimal preserve protection. Protected area planning is not often a step-wise process, but still some aspects of planning depend on prior information or decisions. First should be selected goals for protection and then categories of protected area management. Foresight for design should be applied in reserve site selection and planning and than can be expected less reserve management problems. Regional inventory data are helpful in identifying specific sites. An opportunity in reserve selection is often neglected - using small reserves as a complement for the large reserves. Very important is regional development perspective and local people motivation for cooperation in preserves management. Planning and managing for natural processes is preferable to the traditional view of landform and biota because this processes require more space than the biotic landscape patterns, processes are harder to conceptualize and thus their importance may be underestimated. Planners and reserve managers must be careful by selection of planning goals because popularity of preserve may became superior to scientific or management protection goals. Inovation is key to successful biodiversity protection, and not fortress mentality or an absence of regulations.

As part of field training in Masna Lula Bosnia and Hercegovina several years of their field research, students of the Faculty of Education of the University of Mostar established the presence of newt, Tritus alpestris in the area of hygrophilus meadows near the spring of Jasle. Newts belong to the class of Amphibia, order of Caudata, family Salamandridae

Razvijena je primjenjiva eksperimentalno-analitička metoda za procjenu stanja nosivosti i oštetljivosti postojećih građevina. Ona je primjenjiva i za prijedlog mjera sanacije te za ocjenu kvaliteta izvedenih radova.

U ovom članku prikazan je numerički postupak rješavanja početnih problema upotrebom specijalnih funkcija koje pripadaju klasi Rvačevljevih baznih funkcija Rbf. Korištene su Rbf funkcije iz klase algebarskih i trigonometrijskih polinoma. Zahvaljujući beskonačnoj derivabilnosti ovih funkcija, u numeričkom postupku se direktno koriste svi stupnjevi derivacija koje zahtjeva diferencijalna jednadžba problema i početni uvjeti. Na primjeru jednostepenog sistema dokazana je točnost i stabilnost predloženog numeričkog postupka te je određena veličina kritičnog vremenskog koraka. Razvijen je algoritam za rješavanje višestepenih sistema koristeći kolokacijsku metodu. Numerički rezultati dobiveni pomoću Rbf funkcija uspoređeni su s točnim rješenjima i rezultatima drugih numeričkih postupaka rješavanja početnih problema.

U ovom radu prikazan je postupak za poboljšanje rješenja rubnih zadaća metodom konačnih elemenata, primjenom načela izvorne metode pomaka. Polje pomaka je aproksimirano s dvije vrsti funkcija: baznih funkcija koje zadovoljavaju homogenu diferencijalnu jednadžbu i funkcije pune upetosti na elementu kao partikularno rješenje diferencijalne jednadžbe između čvorova. Funkcije pune upetosti predstavljaju rješenje stanje pune upetosti na elementu. Posljedica je poboljšano rješenje pomaka, deformacija i naprezanja ne samo u globalnim čvorovima nego i iznad konačnih elemenata, i to bez povećanja globalne baze. Razlog je ortogonalnost baznih i funkcija pune upetosti. Načelo je općenito primjenjivo za razne vrste konačnih elemenata. U radu je primijenjeno na linijske konačne elemente okvira i kvadratične konačne elemente savijanja tankih ploča.