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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.

Metode strut-and-tie model merupakan metode perencanaan struktur yang didasarkan padapemahaman tentang adanya daerah D dan daerah B pada struktur beton bertulang. Untuk itu, metodestrut-and-tie model dirintis oleh penelitian yang dilakukan oleh Schlaich [Schlaich et al., 1987] diUni-Stuttgart, Jerman. Selanjutnya berkembang pesat [Adebar et al., 1990; Jirsa et al., 1991; Reineck,1996, 1999, 2002; ACI 318R, 2002, 2005, 2008]. Tujuan penelitian ini adalah mempelajari metodestrut-and-tie model untuk perencanaan balok tinggi beton bertulang, mempelajari simulasi numerikmodel benda uji dengan menggunakan metode elemen hingga dengan ADINA untuk mendapatkanparameter yang diperlukan dalam perencanaan metode strut-and-tie model. Model benda uji dalampenelitian ini diambil dari hasil penelitian eksperimental balok tinggi Hardjasaputra [Hardjasaputra,2006]. Hasil penelitian memperlihatkan bahwa perbedaan %_relatif lendutan balok hasil simulasiADINA terhadap eksperimental berkisar antara 25,49%-27,71%. Perbedaan %_relatif regangan-z hasilsimulasi ADINA terhadap eksperimental berkisar antara 10,53%-17,25%. Penentuan nilai

Fiber reinforced composites have significant usage in aircraft and automotive industries due to their advantages like high strength to weight and stiffness to weight ratios. Short manufacturing cycle time and low production cost are reasons of continued development of additive manufacturing. 3D printing allows to produce reinforced composites but there is necessity to improve printing parameters and propose appropriate fiber deposition with aim to gain suitable mechanical properties. Article is focused on assessment of different options of creating long fibre composite models for 3D printing. These models are reinforced using long aramid, carbon and glass fibres. The goal of paper is analyzing of geometry constraints of fiber adding into structure. In addition, the alternative ways of modelling in FEM software ADINA will be presented.

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 book Difference Equations, Discrete Dynamical Systems and Applications, edited by Saber Elaydi, Christian Potzsche and Adina Luminiţa Sasu, represents selected contributions from the 23rd Inter...

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.

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 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.

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.

Circle of Willis (CoW) is one of the most important cerebral arteries in the human body and various attempts have been made to study the hemodynamic of blood flow in this vital part of the brain. In the present study, blood flow in a patient specific CoW is numerically modeled to predict disease-prone regions of the CoW. Medical images and computer aided design software are used to construct a realistic three-dimensional model of the CoW for this particular case. The arteries are considered as elastic conduits and the interactions between arterial walls and the blood flow are taken into account. Mooney-Rivlin hyperelastic model is used to describe the behavior of arterial walls and blood is considered as a non-Newtonian fluid obeying the Carreau model. An available experimental-based pulsatile velocity profile is used at the entrance of the CoW. The finite element-based commercial software, ADINA, is used to solve the governing equations. Blood pressure and velocity and arterial wall shear stress are calculated in different regions of the CoW. A simplified form of the model is also compared with the available published data. Results affirmed that the proposed computational model has the potential to capture the hemodynamic characteristics of the CoW. The computational results can be used to determine disease-prone locations for a given CoW.

Classical approach for elastohydrodynamic lubrication problems contains solution of Reynolds and elasticity equations simultaneously, where elasticity equation was derived based on semi-infinite solid assumption. Fluid–structure interaction method which uses finite element formulation is another alternative approach for elastohydrodynamic lubrication problems. Present study contains two sections: first finite element method was used to evaluate accuracy of semi-infinite assumption for deformation in an artificial joint cup for a verity of material and geometrical properties. Then fluid–structure interaction method was used to simulate an artificial hip joint lubrication under squeeze film motion and efficiency and accuracy of this method was speculated by comparing the results to a previously done work. In the first section, deformation of a cup under Hertzian contact was calculated by finite element software ADINA. Various combinations of cup thickness, material properties, and dimensions of contact ellipse were modeled and results compared to the answer of semi-infinite assumption and column method for the same problem. Then a ball-in socket configuration for an artificial hip joint was modeled by an ultra-high-molecular-weight polyethylene cup and a Stainless Steel ball in the same software. Fluid film pressure and thickness were extracted from the results and compared to a previous study. Results for deformation of cup show that semi-infinite assumption and column method do not lead to acceptable accuracy for geometrical conditions of artificial hip joint. For fluid–structure interaction analysis of squeeze film motion, at first time steps, pressure distribution shows differences with the previous work, but at last time steps, fluid film pressure matches the previous study. For all time steps, film thickness of fluid–structure interaction method is higher than what was reported by previous work. The main reason is that no mesh independency check was performed for previous work, while for this study mesh independency of answers was analyzed by creating two other models.

This paper presents numerical modelling of wave phenomena in simple elastic structures such as rods and shields made of hyperelastic Zahorski material. The main difference between the Zahorski material, which is an elastic material in the Green sense, and the commonly used Mooney–Rivlin material lies in the non-linear term including the constant C3. Consequently, qualitative and quantitative differences are observed compared to the Mooney–Rivlin material, for example in the values of effective stresses. The extension to the ADINA software developed by the author, which helps create 2D and 3D libraries, significantly facilitates modelling of the Zahorski material. The modification can be used for comparison of wave phenomena that are observed during the propagation of disturbances in the Mooney–Rivlin and Zahorski materials. It should be emphasised that the Zahorski material behaves much better at high strains during the analysis of incompressible rubber and rubber-like hyperelastic materials and can be used in various fields of science wherever the model of Mooney–Rivlin material is successfully applied. The results of numerical computations for both Mooney–Rivlin and Zahorski materials were presented in a graphical form and compared in order to illustrate the differences.

This paper describes the analysis of scaffold frame intersection joint crack. Independent scaffolding type is selected and analyzed for the cracks and deformations. The modelling of the structure is done with the Solid works software and the rendered model was imported to ADINA structures software. All the dimensions for the scaffold design were followed as specified in the standard codes BS4945. Live loads of 2kN/sq.m were taken. The post processing is executed and the results were generated. The results show that maximum bending moment 11.94N-m is at intersection joints particularly at joints. The minimum bending moment -13.44N–m has occurred below the junction the effective stress calculated around the junction of the scaffold is 3.493N/mm2 and the deformation of the scaffolding frame is at intersection joints and the cracks are formed. Visualizing the crack by using ADINA may be the best way to estimate the deformation modes and crack. This will definitely be useful for the remedial measures to prevent cracks in a scaffold structure.

The seismic safety and proper functioning of intake towers in a major earthquake are very crucial to the whole hydraulic project, since the controlled release of the reservoir could help to prevent catastrophic failure of a dam after an earthquake by reducing the water pressure. In this study, the tuned mass damper (TMD) system was introduced into the seismic design of high-rise intake towers. The installation of TMD can effectively dissipate the seismic energy acting on the intake tower and thus overcome the whiplash effect of the hoist room. The 3D finite element model of the intake tower was simplified into a 2D MDOF model. Improved harmony search (IHS) algorithm was used to determine the optimal parameters for the TMD systems using Matlab, and the robustness of the TMD systems was investigated. The simulation elements of the TMD system were incorporated into ADINA to simulate and evaluate the effect of the TMD system on the dynamic displacement and stress responses of various key points of the intake tower to different seismic excitations.

This article is focused on the stress analyses of the welded structure of the device designed to the scales calibrating with maximum loading capacity up to ten tons. The article includes basic knowledges of the theory of elasticity and stress analysis and numerical method called Finite Element Method that were used for the task solution. Cores of the work were stress analyses of selected parts of the designed structure of the device. For stress analyses the ADINA numerical software was used. Results of analyses of the primary design device showed that strength in same locations did not respond to the required maximal load. The structure in critical locations was modified and subsequently reanalyses confirmed the sufficient strength with prescribed safety factor.

Attaining an economical and safe design of structures is regarded as a prerequisite for the structural engineer. The market prices of reinforcing steels have dramatically soared in recent years internationally. Therefore, the purpose of the current paper is not just reducing the ratio of reinforcing steel in the foundations for skeleton structures, but rather minimizing this ratio through choosing the most effective footing shape (folded strip footings). Folded footings have been used as an alternative to the conventional rectangular strip footings. The height of the studied model is ten floors. Two different foundation systems are used in the analysis namely; rectangular strip footings, and folded strip footings respectively. Both footing shapes will be designed as continuous footings with grid shape under the building. Comparison between the two systems is also presented regarding the concrete sections and reinforcement ratio under the same applied loads. The finite element analysis software ADINA is used in modeling and analysis of the structural and geotechnical behavior of both types of footings, with emphasis on the effect of changing the footing shape on the stresses in the footing concrete body and the underlying soils. Research results presents the internal stresses within the footing and soil domains, as well as the contact pressure distribution for a reinforced folded strip footing resting on different soil types. The influence of folding inclination angle, and soil type on the results are also studied. Results showed that folded strip footings are efficient in reducing the amount of needed reinforcements, and such efficiency in reducing the required steel reinforcement in the footings is depending on the applied footing loads, and to some degree on the soil type and properties. Reduction in the reinforcement ratio between the rectangular and folded footing types is about 26% in favor of the folded strip footings. A comparative economical study shows that the total cost of the reinforced concrete section for the folded strip footings is less than the traditional one by about 18%. This difference in cost of both types of footings is mainly due to the relatively smaller in steel reinforcement ratio needed for the folded type as compared with the rectangular ones. So, the folded strip footing is more economical than the rectangular strip footing. Highlights Two different foundation systems are used in the analysis namely; rectangular strip footings, and folded strip footings respectively. The finite element analysis software ADINA is used in modeling and analysis of structural and geotechnical behavior of both types of footings with emphasis on the effect of changing the footing shape and soil type (Ks) on the stresses and soil settlement. Results showed that the maximum value of contact pressure decreased by about 38% for folded strip footing when compared with the traditional strip footing in stiff clay soil, and by about 25% in dense sand soil when increasing vertical static load to its peak value. The reduction in the reinforcement ratio between the two types of footings is about 26% in favor of the folded strip footings. While the total cost of the concrete for the folded strip footings is less than the rectangular one by about 18%. So, the folded shape is more economical than the ordinary rectangular strip footing.

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.