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The main scientific goal of the article is to modernize the methods of designing the rotating mechanisms of working machines (excavators, cranes, backhoe loaders, loaders) and other devices (wind turbines, radars, radio telescopes, drilling machines, wastewater treatment plants) in which the construction of the rotate node uses slewing bearings. In this article, the research will focus on how to mount the bearing to the machine. The calculations will be carried out by numerical modelling of bearings and support structures of machines using the finite element method with the wide use of non-linear FEM techniques and taking into account the elastic-plastic state of deformation in the contact zone. In the research, the ADINA program will be used as the basic numerical calculation tool.

The paper is focused to size and shape influence analysis of inner structures to mechanical properties of the construction created by 3D printing. Analysis is solving in finite element method software ADINA. Foundation of the analysis is a specimen, where have same dimensions and boundary conditions. Boundary conditions replace tensile test with loading 1000N. Aim of the research is to get results (size and shape of the inner structure) of the specimen by tensile test. In results will be outputs (mechanical properties - stress, strain) compared among each other and used next calculations and optimization. Knowledge of these properties is very important in the production of Onyx-based components for the automotive and aerospace industries.

Liquid sloshing is a problem of serious concern in partially liquid filled containers mounted in the moving vehicle or structure. An analytical technology is developed to solve the dynamic response of the liquid in the circular cylindrical container with multiple rigid baffles subjected to the pitching excitation. The generalized coordinates are introduced to expand the free surface elevation and the velocity potential, which contains the Stokes-Joukowski potential. Based on the partition of the liquid domain, a new method is developed to obtain the analytical solution of the Stokes-Joukowski potential. According to the kinematic and dynamic boundary conditions on the free surface, the dynamic response equation can be established. The analytical model for liquid sloshing is validated with the numerical results obtained from the commercial software ADINA. Systematic parametric investigations are carried out to reveal the effects of baffles’ parameters and the pitching excitation frequency on the responses of the liquid.

The submitted paper is devoted to the numerical modeling of the dynamic effects of moving vehicles on concrete pavements. The finite element method, namely the ADINA program, is used to model the problem. To solve the task, it is necessary to create a vehicle and a road computational models. The vehicle model is spacious and corresponds to a heavy truck of the Tatra type. The so-called single-layer road model on an elastic Winkler foundation is used. Concrete pavements are modeled using shell or solid elements. The output of the solution is the time course of the dynamic deflections at the individual points of the slab and internal forces and the stress states in the concrete slab at the individual time points of the solution. The calculation results for each computational model are compared to each other.

Mitochondrial DNA cytochrome oxidase (COI) and microsatellite DNA loci were used to better explain the speciation events, history of hybridization, and genetic population structure of the stone crabs Menippe adinaWilliams & Felder, 1986 and M. mercenaria (Say, 1817–1818). A survey of a 670-bp COI sequence of 711 stone crabs collected from Texas to North Carolina and from Belize, Central America showed the presence of two well-defined mtDNA lineages, Lin-A and Lin-B. Based on molecular clock calibrations of a published study these lineages shared a common ancestor between 1.5 to 1.8 million years. Lin-A was evident throughout the range of the two Menippe species, but Lin-B was found only in the eastern Gulf of Mexico and does not represent any of the two species. Our findings refute the claim that the eastern Gulf hybrid zone is the product of hybridization between M. adina and M. mercenaria. We propose that the hybrid zone is instead a relic of introgressive hybridization between the M. mercenaria of eastern Gulf stone crab nDNA Lin-AA that carries Lin-A and the new nDNA Lin-BB that carries Lin-B, forming the hybrid nDNA Lin-AB. Lin-B emerged from a founder effect in the Okefenokee Trough and introgressed into the eastern Gulf. There is no Lin-B in the Atlantic, hence no hybridization in that region. Using stone crab-specific microsatellite markers we found no evidence of an ongoing hybridization in the eastern Gulf and this region cannot be called a hybrid zone since hybridization here ceased probably soon after the last glacial episode. The microsatellite-marker analyses also suggested that the stone crab was geographically divided into four genetic clusters by three barriers to gene flow, the strongest of which is the one between the two species, M. adina and M. mercenaria, around Cape San Blas, Apalachicola Bay, Florida.

45 p. : il. -- Bibliogr.: p. 32-36 [EUS] Lan honen helburua, nagusiki, Lehen Hezkuntzako ikasleen autokontzeptuan sexuaren eta adinaren arabera egon daitezkeen aldeak aztertzea izan da. Ebaluatutako lagina Amurrioko Lucas Rey HLHIko Lehen Hezkuntzako 7 eta 13 urte bitarteko 100 ikaslekoa izan da. Horietatik 46 (%46) lehen ziklokoak dira eta 54 (%54) bigarren ziklokoak, horien artean 49 (%49) neskak eta 51 (% 51) mutilak. Ikasle hauen autokontzeptua neurtzeko Piers Harrisen inkesta erabili da. Inkesta honek ikasleek beren buruaz duten pertzepzioari buruzko informazioa lortzeko aukera ematen du (autokontzeptu globala), bai eta autokontzeptuak barne hartzen dituen alderdiei buruzkoa ere, 6 dimentsioen bidez (izendatu dimentsio horiek). Lortutako datuek ez dute autokontzeptuaren dimentsioetan sexuaren araberako alde esanguratsurik adierazten. Aldiz, adinari dagokionez, lortutako emaitzek adierazten dute ikasle zaharrenek estatistikoki puntuazio hobeak lortzen dituztela autokontzeptu konduktualean, sozialean eta zoriontasun-asebetetzean. Hobekuntza proposamena bezala, autokontzeptu sozialaren garapen positiboa lantzeko. Lehen Hezkuntzako 3. eta 4. mailako ikasleei zuzendutako esku-hartze proposamen bat aurkezten da. Autokontzeptuaren dimentsio soziala hobetzeko, 5 jarduera proposatzen dira, eta horietan gizarte-trebetasunak landuko dira; izan ere, trebetasun horiek funtsezkoak dira beste pertsona batzuekin harremanetan jartzeko edo gizarte-eremuan behar bezala moldatzeko. [ES] El objetivo de este trabajo ha sido principalmente analizar las posibles diferencias en el autoconcepto del alumnado de Educación Primaria en función del sexo y la edad. La muestra evaluada ha sido de 100 alumnos de 7 a 13 años del CEIP Lucas Rey HLHI de Amurrio. De los cuales 46 (46%) son de primer ciclo y 54 (54%) son de segundo ciclo, entre ellos 49 (49%) son niñas y 51 (51%) son niños. Para medir el autoconcepto de estos alumnos se ha utilizado la encuesta de Piers Harris. Esta encuesta permite obtener información sobre la percepción del alumno (autoconcepto global) y sobre los aspectos que incluye el autoconcepto a través de 6 dimensiones. Los datos obtenidos no muestran diferencias significativas según el sexo en las dimensiones del autoconcepto. Por el contrario, en cuanto a la edad, los resultados obtenidos indican que el alumnado de mayor edad obtiene mejor puntuación estadísticamente en autoconcepto conductual, social y satisfacción de felicidad. Como una propuesta de mejora, para trabajar el desarrollo positivo del autoconcepto social. Se presenta una propuesta de intervención dirigida al alumnado de 3º y 4º de Educación Primaria. Para mejorar la dimensión social del autoconcepto se proponen 5 actividades en las que se trabajarán habilidades sociales; ya que son fundamentales para relacionarse con otras personas o desenvolverse adecuadamente en el ámbito social. [EN] The aim of this work has been mainly to analyse possible differences in the self-concept of primary school pupils according to sex and age. The evaluated sample has been 100 students from 7 to 13 years old from CEIP Lucas Rey HLHI in Amurrio. From these, 46 (46%) are in the first cycle and 54 (54%) are in the second cycle, including 49 (49%) girls and 51 (51%) boys. The Piers Harris survey was used to measure the self-concept of these pupils. This survey allows us to obtain information on the student's perception (global self-concept) and on the aspects included in the self-concept through 6 dimensions. The data obtained does not show significant differences according to sex in the dimensions of self-concept. On the contrary, in terms of age, the results obtained indicate that the older students obtain a statistically better score in behavioural and social self-concept and happiness satisfaction. As a proposal of improvement, to work the positive development of the social self-concept. A proposal of intervention directed to the students of 3rd and 4th grade of Primary Education is presented. In order to improve the social dimension of the self-concept, 5 activities are proposed in which social skills will be worked; since they are fundamental to relate to other people or to develop adequately in the social field.

Shallow foundations resting on a deep layer of soft saturated clay are considered a geotechnical challenge. The design engineer is faced with challenges in selecting safe and economic solutions for the foundations of these light weight structures by turning to the shell-shaped foundations to deal with such foundation problems and avoid the use of the costly deep foundations or other soil improvement schemes. This paper introduces different bottom of foundations shapes resting on extended soft clay layer in an effort to minimize the soil stresses and reduce the settlements. Elliptical, trapezoidal and inverted folded footings have been used as an alternative to the conventional flat bottom shallow footings. The purpose of the current study is to reach the optimal shape of the foundations, which achieves reduced stresses, reduced settlements and consequently cost. The geotechnical behavior of different bottom of foundation shapes resting on saturated soft clay is investigated experimentally and numerically. The experimental investigation started with studying a model for the conventional square flat footing shape resting over saturated soft clay. Elliptical, trapezoidal and inverted folded bottom of foundation models are tested and compared with the reference conventional square flat ones. In addition to the experimental study, a numerical analysis is performed using the finite element software ADINA. Verification of the numerical model is conducted first against the experimental results for all the studied cases. The verified numerical model is then extended to cover full-scale footing sizes of conventional and other studied footing cases and shapes. The optimum bottom of foundation shape is the one that gives the lowest soil stresses and consequently the lowest settlements.

Design scheme of steel shell flow tube in the inflow and outflow passage of the vertical axial pumping stations takes advantages of conventional concrete scheme in simple construction and convenient installation of the pump. A three-dimensional pumping station model was established based on fluid-structure interaction method in ADINA. Typical measure points were selected to analyze the features of the unsteady turbulent flow in fluid zone and vibration responses of the steel shell tube in solid zone. Time and frequency domain investigation of fluid domain revealed the transmission path of pressure pulsation, that was the pulsation transferred from the pump to the inlet and outlet respectively with amplitudes sharply decreasing, which verified the rationality of calculation and established the basis on structure analysis. Dynamic displacement, velocity and acceleration analysis of measure points in steel shell tube showed that top shell domain near the inlet of steel shell flow tube had obvious vibration amplitude, which required great attention. The first main frequency equaled the rotational frequency of the blade, indicating one of the most important vibration sources in the pump was the pressure pulsation induced by blade rotation. The design scheme of steel shell flow tube is practical and could be promoted to other similar pumping stations because the vibration amplitude is much lower than the regularity. This research provides great importance to the design and application of the steel shell flow tube in pumping stations.

The effects of seawater and site conditions on the seismic response of the isolated continuous girder bridge are evaluated in this study. The seawater-muddy soil-isolated bridge coupling model is built in the dynamic analysis software ADINA, and the external seismic wave input is realized by the seismic wave motion analysis program. The influences of seawater and muddy soil on the seismic response of isolated continuous girder bridges are determined by comparing different offshore site models. The results indicated that the seawater and the muddy soil magnify the displacement of the seabed. The existence of seawater increases the longitudinal relative displacement of piers by 20%–40% but has limited influence on the bending moment and shear force of piers. The muddy soil can increase the longitudinal relative displacement and internal force of the piers remarkably. Moreover, the displacement of bridge bearings increases significantly under the combined influence of muddy soil and seawater. In the seawater-muddy soil-isolated bridge coupling model, the seawater and site condition can influence the seismic performance of sea-crossing bridges obviously.

Mitral insufficiency is the first valvular disease worldwide, with a 2% prevalence. When open-heartsurgery is impossible for the patient, surgeons use percutaneous devices to help the mitral leaflets coapt. However, the only device currently available is based on the edge-to-edge mitral valve repair technique. This type of implant is not adapted for patients suffering from functional mitral insufficiency, where the ventricle is responsible for the lack of coaptation of the leaflets. This thesis aims to provide a numerical platform to help the development of a mitral valve implant adapted for those patients. Several mitral valve geometries were created from a parametric model using anatomical measurements. Finite element simulations of the mitral valve were performed using ADINA to determine the valve closure under constant pressure. Several material models were developed in large strain and large deformation to model the valve closure accurately. Pathological behaviour such as annulus dilatation and chordae rupture were modelled, and several methods were tested to implement medical devices. Fluid-structure interaction of a 2D mitral valve was obtained using an ALE description and a monolithic coupling approach. Both the systole and the diastole were reproduced and studied, and the hermetic seal of the valve was detailed. The numerical platform developed is suited to model mitral valve function and can be used to help the development of mitral implants. In addition, the parametric geometry model and the anisotropic material model will be useful to depict with realism the valve function. A 3D fluid-structure interaction of the mitral valve could be developed., L’insuffisance mitrale est la valvulopathie mondiale la plus fréquente avec une prévalence de 2%. Lorsque le patient n’est pas en mesure d’être opéré à cœur ouvert, un implant percutané est utilisé pour aider la fermeture des feuillets. Le seul implant actuellement disponible est basé sur la réparation bord à bord de la valve mitrale. Il réduit le reflux vers l’oreillette lors de la systole, mais n’est pas adapté pour les patients souffrant d’insuffisance mitrale fonctionnelle, chez qui la pathologie provient du ventricule et non des éléments de la valve. L’objectif de la thèse est de fournir une plateforme numérique permettant d’aider au développement d’un implant adapté pour ces patients. Plusieurs géométries de valve ont été réalisées au moyen d’un modèle paramétrique, en utilisant des données anatomiques. La dynamique de la valve a été modélisée avec le logiciel ADINA par des simulations éléments finis en grandes déformations. Des modèles structurels de la valve ont permis de représenter la fermeture de la valve sous une pression uniforme. Les lois de comportement de matériaux ont été développé dans le but d’obtenir une fermeture réaliste de la valve. Cela a nécessité la prise en compte de l’hyperélasticité et de l’anisotropie des tissus. Des pathologies valvulaires, telles que la dilatation de l’anneau mitrale ou la rupture des cordages tendineux ont été modélisées, et plusieurs méthodes ont été testées pour y apposer des systèmes médicaux. En utilisant une description ALE et un couplage monolithique, les interactions fluide-structure ont été simulées pour une valve mitrale bi-dimensionnelle. La fermeture hermétique de la valve pendant la systole a pu être reproduite et l’ouverture de la valve étudiée pendant la diastole. La plateforme numérique développée permet de modéliser la fonction de la valve mitrale et peut être utilisée pour aider au développement d’un implant mitral grâce au modèle paramétrique reproduisant différentes géométries de valve et aux lois matériaux anisotropes. Une perspective reste la création d’un modèle 3D des interactions fluide-structure de la valve mitrale.

In the deep sea mining system, the lifting pipe is a special articulated cantilever pipe, which is prone to large deviations and bending deformations. The finite element plane beam element idea is used to discretize the dynamic differential equation of the lifting pipe, and the vibration balance equation of the lifting pipe affected by internal flow is established. Through the computer simulation software ADINA, the model of lifting pipe and internal flow is established, and the computer simulation process is determined. The computer simulation results show that under different working conditions, the maximum stress of the lifting pipe acts on the top of the lifting pipe, and the maximum offset occurs at the bottom of the lifting pipe. When the internal flow is considered in the lifting pipe, the maximum stress at the top of the pipe increases gradually and the maximum lateral displacement at the bottom of the pipe increases gradually with the increase of the internal flow velocity.

This work focuses on subcooled boiling heat transfer during flow in a minichannel heat sink with three or five minichannels of 1 mm depth. The heated element for FC-72 flowing along the minichannels was a thin foil of which temperature on the outer surface was measured due to the infrared thermography. The test section was oriented vertically or horizontally. A steady state heat transfer process and a laminar, incompressible flow of the fluid in a central minichannel were assumed. The heat transfer problem was described by the energy equations with an appropriate system of boundary conditions. Several mathematical methods were applied to solve the heat transfer problem with the Robin condition to determine the local heat transfer coefficients at the fluid/heated foil interface. Besides the 1D approach as a simple analytical method, a more sophisticated 2D approach was proposed with solutions by the Trefftz functions and ADINA software. Finite element method (FEM) calculations were conducted to find the temperature field in the flowing fluid and in the heated wall. The results were illustrated by graphs of local heated foil temperature and transfer coefficients as a function of the distance from the minichannel inlet. Temperature distributions in the heater and the fluid obtained from the FEM computations carried out by ADINA software were also shown. Similar values of the heat transfer coefficient were obtained in both the FEM calculations and the 1D approach. Example boiling curves indicating nucleation hysteresis are shown and discussed.

This article is divided into two parts&mdash, in the first part, authors inform about their testing device that enables the acquisition of results from uniaxial and multiaxial fatigue tests (the bending&minus, torsion combination). We present the approaches used during designing and building the testing device. The direct implementation of the research in the second part will concentrate on implementing the acquired results for the frame design of a vehicle worked out by the authors. The three-wheeled vehicle has the front steered wheel suspended in an unconventional way. This original design can cause an increased load on the vehicle&rsquo, s frame. This can be apparent mainly during driving through curves. Therefore, the fatigue curves of the tested material (EN AW 6063) will be implemented from the point of view of its usability in operation. A vehicle frame is most often loaded by bending and torsion. The authors assess the influence of welding on the fatigue life of this unique unconventional vehicle by determining the fatigue curves of the material for its production. The stresses achieved on the test specimens fully correspond to the load of the frame (in welds) during its operation.

At some coastal areas in Egypt, especially Port Said and Damietta, there are layers of loose to medium silty sand with traces of seashells fragments at the surface, overlying a very deep soft clay layer. The construction of shallow foundations over such soil formation is difficult and in some cases is not possible due to the high soil compressibility, large settlements, low bearing capacity, and near surface groundwater. In such case, small diameter piles could be used especially under low rise structures to transmit the structure loads with much lower settlements. A finite element-based numerical analysis using ADINA software (Version 9.4.2) ‎[4] is used to analyze and study the behavior of piles in such soil formations. Results indicated that both pile diameter and embedded length in loose sand have significant effect on the pile capacity and settlement on the other hand pile embedded length in soft clay layer has no effect on either pile capacity or pile settlement. One of the key findings of this study is that, most of the load carried by the pile transmitted to soil by skin friction so that, the choice of using pile foundation in such soil formations is practical to some extent.

In Egypt, large diameter piles are used in some sites with diameters exceeding 2 m. In some cases, these piles carry foundations of heavy structures and/or large vertical and lateral loads. The analysis and design methodologies of large diameter piles are mainly controlled by the relatively smaller diameter piles, usually ranging between 60 and 120 cm. However, there is a special need for the analysis and design of larger diameter piles (i.e., larger than 120 cm) to assess their actual load carrying capacities. This paper presents numerical modeling of end bearing piles constructed in thick layer of soft to very soft clay underlain by a dense sand layer, typical to large zones in Northern and North Eastern zones in Egypt. The finite element analysis software ADINA (2018) [2] is used to simulate the behavior of the large diameter bored piles. Results showed that increasing the pile diameter cause a corresponding increase in pile capacity. It is also noticed that increasing pile embedded length in the end bearing sand layer has an enormous effect on pile capacity especially for larger diameter piles.

The computing finite element model of the elastic-frictional draft gear was developed with application of the Siemens NX software package. The theoretical foundations of computational methods laid in the NX Nastran software system were analyzed. The optimal solver settings that make it possible to achieve the convergence of the solution without sacrificing acceptable accuracy were determined.

Cellular polymer foams find extensive applications as energy absorbers under static, impact and blast loads due to their capacity to absorb energy under constant stress up to full densification strain (Ashby et al. Metal foams: a design guide. Butterworth-Heinemann, Oxford, 2000 [1]; Gibson and Ashby, Cellular solids: structure and properties. Cambridge University Press, Cambridge, 1999 [2]). In the present paper, the material characterization of natural latex cellular polymer foam used in the field air blast experiments (Venkataramana et al. Proc Eng 173:547–554, 2017 [3]; Venkataramana et al. Numerical simulation of blast wave mitigation using foam impregnated with water. DAE BRNS Symposium on Multiscale Modeling of Materials and Devices (MMMD-2014), 2014 [4]) performed to assess the blast mitigation effect of fluid-filled open-cell pin-core polymer foam is presented. Static compression tests were performed to study the quasi-static behavior of the pin-core latex polymer foam. The Ogden hyper-elastic material parameters are determined from the analysis of static compression test data using ADINA (automatic dynamic incremental nonlinear analysis) v 9.2, ADINA R&D, Inc., Watertown [5]). Further, results of the static compression tests on dry foam and water-saturated foam are compared and discussed. In addition, the dynamic behavior of the pin-core latex cellular foam is investigated by conducting drop tower impact experiment and numerical simulation of the drop tower experiment using LS-DYNA (LS-DYNA v971, Livermore Software Technology Corporation, Livermore [6]). The stress–time history from the drop tower experiment is compared with that of simulation, and good correlation is found between the two sets of results.

Aiming at solving the problem of low unloading sensitivity, bad dynamic performance and poor stability of high-pressure and large-flow relief valve in hydraulic support system, a new differential type of high-pressure and large-flow relief valve, functioned by high water-based hydraulic medium, is designed. Through analysing the influence of spool form, elastic element, and working principle on valve performance, a structural scheme of large-flow and high-pressure safety valve is put forward. The three-dimensional fluid–solid coupling model of differential safety valve is established; through ADINA software, three-dimensional fluid–solid coupling simulation of relief valve's orifice from shutdown to full opening is carried out to analyse the distribution of internal pressure in the flow field of the safety valve and the pressure change of the structure field. The physical simulation model of safety valve is established by using AMESim software, and the dynamic performance of safety valve is simulated under the given signal of nominal flow and small flow. According to the design structure, the safety valve with the rated flow of 3000 L/min is manufactured and tested. The simulation and experimental results show that the safety valve has good dynamic performance and high sensitivity..

The aim of the work was numerical analyses of a steel-concrete composite column and a steel column. An internal column 3.60 m in length was considered. The column was on the second storey of a six-storey building designed for retail and services. The column was subjected to compression and uniaxial bending. The existing steel column was made from a welded H-profile. In the first stage of the work, the composite column was designed as an alternative to the existing steel column using the analytical method. A steel reinforced concrete column with a steel H-profile was selected. The second part of the work consisted in modelling the steel and composite columns. The geometries, loads and boundary conditions used in simulations of the columns were the same as in the analytical calculations. Numerical analysis was carried out using the ADINA System based on the finite element method. In the steel column, the stresses and displacements were considered. In the composite column, the stresses in the steel and concrete elements, the stresses distributions in the reinforcement bars and displacements of the whole column were evaluated.

The thermal incompatibility between fiber reinforced polymer (FRP) bars and concrete may cause splitting cracks within the concrete and, eventually, the deterioration of the bond between the FRP bar and the concrete. This paper presents a numerical study using ADINA finite elements software to investigate the thermal behavior of actual one-way concrete slabs reinforced with glass FRP (GFRP) bars varying the ratio of concrete cover thickness to FRP bar diameter (c/db) from 1.3 to 2.8. Slabs are submitted to temperature variations varied from −50 to 60 °C. The main results prove that first radial cracks occur in concrete, at the FRP bar – concrete interface, at thermal loads (ΔTcr) varied between 15 °C and 30 °C. While, the circumferential cracks appear within concrete, at FRP bar – concrete interface, at ΔTcr varied between −15 °C and −35 °C depending of the ratio c/db (1.3 to 2.8) and the tensile strength of concrete fct (1.9 to 2.9 MPa). These numerical thermal loading values are relatively in good agreement with those predicted from the analytical model. The numerical model shows that there is no failure of the concrete cover for low temperatures for slabs having c/db = 1.3 to 2.8 and fct = 1.9 to 2.9 MPa. Nevertheless, for high temperatures, the splitting failure of concrete cover is produced at thermal loads ΔTsp′ varied from 30 °C to 59 °C. While, for concrete situated between GFRP bars, the splitting failure occurred at thermal loads ΔTsp′ equal to 46 °C. Thermal stresses and strains, and also cracking thermal loads predicted from the numerical model are compared with those obtained from analytical models and experimental tests.

The presentation of the plastic zone for flexural members is basic as it administrates the load carrying and deformation capacities of the member. Therefore, plastic hinge study has been of great attention to structural researchers for decades. The behavior of plastic hinge is very tricky due to the high nonlinearity of materials, and relative movement between the component materials and strain localization. As a result, most researchers investigated the problem experimentally or by using programs which depend on the materials nonlinearity such as ANSYS, ABAQUS or ADINA programs. This paper tries to investigate the problem analytically by proposing a simple approximate equation to compute the plastic hinge rotation. A lot of parameters such as the tension and compression steel ratios, concrete strength, steel yield, section geometry and the load position were considered in the suggested equation. The analytical results of simply supported beams under middle concentrated load with different parameters were presented and compared with the conjectures of the various formulations, software programs (ANSYS and NONLACS2) and experimental results. The simplified suggested equation gave satisfying results. Moreover this paper presented a structural mathematical model based on the suggested equation to predict the deformations behavior of the beams. The plastic rotation and deflections can be predicted by the mathematical model after yielding till the failure moment, not only at the failure moment as in the common formulations. The mathematical model was verified and gave values of deflections matching experimental results.

The object of the present research concerns the structural response of Xana, one of the earliest khans in the Balkan area, located in the archeological site of the municipality of Traianoupolis, Evros, Greece, due to static and seismic loading. The main research question is twofold: (a) what are the causes of nowadays structural pathology; and (b) what is the most adequate restoration scheme. The main methods used for the research refer to historical and bibliographical survey, experimental testing of the monument’s materials and nonlinear numerical analyses conducted by the used of the finite element code ADINA. Therefore, two 3D nonlinear finite element models were constructed by the use of ‘birth’ and ‘death’ element option. The first model refers to the initial monument’s stage till its current stage and the second model refers to its current stage till the restoration proposal. The results refer to the displacement field and failure figure due to static and dynamic loading, under the prism of a pushover analysis. Taking into account soil-structure interaction, the accurate structural geometry and staged construction proved to be essential for the correct estimation of the structural behavior. The absence of wooden tendons in combination with the large self-weight of the structure is the main reason of the monument’s pathology. Therefore, the restoration proposal includes the construction of a light-weighted roof and the function of steel tendons.

This work revealed the flood damage rule of road-bridge binding sites in highway bridge engineering according to the Fr similarity criterion by adopting the orthogonal test design method and emphasizing, exploring, and analyzing the influence degree of flood damage on the model while considering the length into fluid of the model, the included angle between the model and the fluid direction, the slope ratio of the model, and the existence of protective measures for the model. According to a comparison and an analysis, ADINA finite element numerical calculation and model test results coincided perfectly. Findings suggested that when the length of the fluid into the model is long, the extent of the damage of the model structure body is serious. After water scouring the model, and when the included angle between the model and the fluid direction was set at 135 degrees, the deposits was enlarged and dispersed, the scouring depth was significant, and the model was nearly completely destroyed. The slope surface could effectively decompose the fluid velocity with its strong anti-scouring capability given a certain slope ratio of the model. The protective measures of grouting layers or cofferdams could fully protect the model structure body. These results provide important references for enriching the flood damage mechanism of road-bridge binding sites and the safety operation of related highway bridge engineering.

A pipeline with an extended blockage is modelled as a system of three pipes in series. A computational fluid dynamics approach using the ADINA software is adapted to solve the slightly compressible...

Fiber-reinforced polymer (FRP) bars are being increasingly used in civil engineering constructions due to their excellent properties in comparison with steel bars, especially in terms of corrosion resistance. Designers generally adopt over-reinforced sections to avoid a sudden failure mode of FRP bars. Therefore, the overlap of the bars is omnipresent. However, under large temperature increase, the overlap area may be regarded as a zone of radial stress concentration generated by a pressure caused by the thermal expansion of both bars. Several studies have been conducted on the thermal behavior of FRP bars-reinforced concrete elements, but none of these studies has taken into account the overlapping effect of bars under high temperature. The aim of this study is to develop numerical and analytical models to predict transverse thermal strains and stresses in FRP bars interaction zone by varying the ratio of concrete cover thickness to FRP bar diameter ( $$c/d_\mathrm{b})$$ from 1 to 3.2, and the temperature increases from 0 to $$+\,60\,^{\circ }\hbox {C}$$ for concrete beams reinforced with two overlapped glass FRP (GFRP) bars. The numerical model is developed using ADINA finite element software, and its results are compared with those obtained from the analytical model based on linear elasticity theory.

The use of circular steel flange plates with circular bolts pattern connections is common in tubular structures used in different applications such as transmission and communication structures. Several published literatures include methods for the design of these connections under tension loads. These methods are not widely used in the industry as they are either complex or yielding results that are not always consistent with published test data. Therefore, there is still a need for a simplified, yet accurate, method for designing these connections when subjected to tension loads. This paper presents a numerical study performed on circular flanged connections subjected to concentric axial tension loads. The analysis part of the study is conducted using the Finite Element (FE) package ADINA considering one common geometrical flange plate configuration, ring configuration, while considering contact surface separation. The results obtained from the FE analyses are compared with published experimental data from which it is concluded that the FE model can predict the behaviour of these connections with a high degree of accuracy. Parametric investigation is then conducted to numerically expand the experimental data to gain more insight into the behaviour of these flange plate connections and to use this data later in this work to validate the proposed design method. The varying parameters considered in the numerical investigation include base plate thickness; number of bolts; bolt circle diameter and plate diameter. A simple design approach based on yield line theory is then introduced and a comparison between yield loads predicted using the proposed model and the finite element results is presented. The yield loads resulting from proposed design method show good agreement with the finite element results with 10% maximum difference.

In this paper the comparative analysis of obtained stress and displacements results from two different FEM programs – Robot Structural Analysis and ADINA was performed. As a subject of the analysis, the numerical model of the arch footbridge in steel construction was adopted.

The work presents the parametric study of a steel–concrete composite beam with composite dowel connectors. The designed beam is located in a highly loaded warehouse ceiling with a useful load of 20 kN/m2. In the first part of the work, the best solution of the composite dowel beam was selected from among 7 variants. The parameterization of the composite beam was made on the basis of the following parameters determined by numerical calculations: mass of the steel part, vertical deflection of the beam, stresses in the steel and concrete, and the character of concrete cracks. Then in the second part of the work, the best variant of the beam with composite dowels was compared with the commonly used solution of a composite steel–concrete beam with headed stud connectors. In the numerical model, the finite element method was used to describe the influence of mechanical loads on the strains and stresses in the floor beam. Numerical calculations were made using the ADINA System based on FEM. A model was built from 3D-solid elements. However, the reinforcing bars were modelled with truss elements (rebar elements). The applied boundary conditions reflected the freely supported composite beam. The advanced concrete model available in the ADINA System program was used to simulate concrete, assessing the possibility of concrete cracking.