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The Theory used in ADINA is richly documented in the following books by K.J. Bathe and co-authors



To Enrich Life
(Sample pages here)

Following are more than 700 publications — that we know of — with reference to the use of ADINA. Since there are numerous papers published in renowned journals, we can only give here a selection. The pages give the Abstracts of some papers published since 1986 referring to ADINA. The most recent papers are listed first. All these papers may be searched using the box:

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Natural frequency analysis of shells of revolution based on hybrid dual-mixed hp-finite element formulation

Tóth, B.1

1 Institute of Applied Mechanics, University of Miskolc, Miskolc-Egyetemváros, H-3515, Hungary

Applied Mathematical Modelling, Volume 98, October 2021, Pages 772-746

Abstract: A newly-developed, dimensionally reduced, hp-type axisymmetric shell finite element model is extended to linear elastodynamic problems of thin shells of revolution. The hp-shell finite element relies on the hybridized version of a three-field dual-mixed variational formulation, the application of which dictates the obligate usage of the inverse three-dimensional constitutive relation for homogeneous and isotropic materials, thereby ensuring the volumetric locking-free characteristic of the shell model at theory level. The fundamental fields are the a priori non-symmetric stress tensor, the displacement vector, the infinitesimal rotation vector and the hybrid variable defined on the element interfaces. Since the dimensional reduction process guided by this hybrid-mixed formulation does not necessitate the use of any classical kinematic assumptions appearing in the scientific literature, the inverse 3D Hooke’s law does not have to be modified. The numerical performance of the shell finite element is analyzed comprehensively for natural frequency computations of clamped-free and simply supported, silicone, conoid, spherical and hyperboloid shells of revolution. From their relative error convergence behaviors it follows that the extended hybrid-mixed shell finite element is not sensitive to the decrease of the slenderness ratio, namely providing reliable, uniformly stable numerical results for both h- and p-approximation. From theoretical point of view, the beneficial properties of the hybrid-mixed hp shell finite element model are as follows: (i) this is effectively applicable to modeling not only extremely thin but also moderately thick shell structures with transverse shear deformations, as well as (ii) both the through-the-thickness variation and the membrane stress normal to the shell mid-surface are retained as independent variables, making it much easier to upbuild shell model for contact problems. From numerical point of view, the nice feature of the hybrid-mixed hp shell finite element is that the global flexibility matrix of the system can be inverted block-wise at element level at cheap computational cost during the assembling procedure because of the hybridization technique.

Keywords: Hybridization - Dual-mixed formulation - hp-finite element - Shells of revolution - Elastodynamics - Natural frequency analysis


Parametric studies on sloshing in a three-dimensional prismatic tank with different water depths, excitation frequencies, and baffle heights by a Cartesian grid method

Jin, Q.1 , Xin, J.2, , Shi, F.3, Shi, F.2

1 Faculty of Engineering and the Environment, University of Southampton, Southampton, SO167QF, UK
2 Department of Biomedical Engineering, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239, United States
3 School of Shipping and Naval Arechitecture, Chongqing Jiaotong University, Chongqing, 400074, China

International Journal of Naval Architecture and Ocean Engineering, Available online 6 September 2021

Abstract: This paper aims to numerically investigate violent sloshing in a partially filled three-dimensional (3D) prismatic tank with or without a baffle, further to clarify the suppressing performance of the baffle and the damping mechanism of sloshing. The numerical model is based on a Cartesian grid multiphase flow method, and it is well validated by nonlinear sloshing in a 3D rectangular tank with a vertical baffle. Then, sloshing in an unbaffled and baffled prismatic tank is parametrically studied. The effects of chamfered walls on the resonance frequency and the impact pressure are analyzed. The resonance frequencies for the baffled prismatic tank under different water depths and baffle heights are identified. Moreover, we investigated the effects of the baffle on the impact pressure and the free surface elevation. Further, the free surface elevation, pressure and vortex contours are analyzed to clarify the damping mechanism between the baffle and the fluid.

Keywords: Cartesian grid method - Violent sloshing - Prismatic tank - Baffle height - Resonance frequency


Porcine and bovine aortic valve comparison for surgical optimization: A fluid-structure interaction modeling study

Li, C.1 , Tang, D.2,3 , Yao, J.4, Shao, Y.5, Sun, H.5 , Hammer, P.6 , Gong, C.7, Ma, L.5, Zhang, Y.4, Wang, L.2 , Yu, H.2, Yang, C.8, Baird, C.6

1 School of Mathematics, Southeast University, Nanjing, China
2 School of Biological Science & Medical Engineering, Southeast University, Nanjing, China
3 Mathematical Sciences Department, Worcester Polytechnic Institute, Worcester, MA, USA
4 Department of Cardiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
5 Department of cardiovascular surgery, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
6 Department of Cardiac Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
7 Department of anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
8 China Information Tech. Designing & Consulting Institute Co., Ltd., Beijing, China

International Journal of Cardiology, Volume 3341, 1 July 2021, Pages 88-95

Porcine aortic valve (PAV) and bovine aortic valve (BAV) are commonly used in aortic valve replacement (AVR) surgeries. A detailed comparison for their hemodynamic and structural stress/strain performances would help to better understand valve cardiac function and select valve type and size for AVR outcome optimizations.
Eight fluid-structure interaction models were constructed to compare hemodynamic and stress/strain behaviors of PAV and BAV with 4 sizes (19, 21, 23, and 25 mm). Blood flow velocity, systolic cross-valve pressure gradient (SCVPG), geometric orifice area (GOA), flow shear stresses (FSS), and stress/strain were obtained for comparison.
Compared with PAV, BAV has better hemodynamic performance, with lower maximum flow velocity (7.17%) and pressure (9.82%), smaller pressure gradient (mean and peak SCVPG: 8.92% and 9.28%), larger GOA (9.56%) and lower FSS (6.61%). The averages of the mean and peak net pressure gradient values from 4 BAV models were 8.10% and 8.35% lower than that from PAV models. Larger valve sizes for both PAV and BAV had improved hemodynamic performance. Maximum flow velocity, pressure, mean SCVPG and maximum FSS from 25 mm BAV were 36.80%, 15.81%, 39.05% and 38.83% lower than those from 19 mm BAV. The GOA of PAV and BAV 25 mm Valve were 43.75% and 33.07% larger than 19 mm valves, respectively. BAV has lower stress on the leaflets than PAV.
BAV had better hemodynamic performance and lower leaflets stress than PAV. More patient studies are needed to validate our findings.

Keywords: Aortic valve replacement - Fluid-structure interaction - Porcine aortic valve - Bovine aortic valve


Theoretical analysis and finite element simulation of pipeline structure in liquefied soil

Yang, C., Li, S.1

1 MOE Key Laboratory of Disaster Forecast and Control in Engineering, School of Mechanics and Construction Engineering, Jinan University, Guangzhou, China

Heliyon, Volume 7, Issue 7, July 2021, e07480

Abstract: A mechanical analysis model for the floating of buried pipelines in soil liquefaction areas is established in this paper. In order to improve the inherent defects of the elastic foundation beam method based on the Winkler model and increase the calculation accuracy, the Pasternak model is introduced and the interaction between soil and spring is considered. A mechanical analysis method for buried pipelines in liquefaction zone considering axial load is proposed in present paper. According to the Pasternak model and the deflection curve differential equation, the pipe bending deformation curve equation and the deformation coordination equation are derived. The analytical calculation method of the pipe mechanical response is established. A new method of the mechanical analysis of the floating of buried pipelines in the liquefaction zone is provided. The mechanical response of the pipeline under the conditions of different pipeline parameters and liquefaction zone length is analyzed. The reliability of the analysis method in this paper is verified by the comparison of finite element method (FEM). Considering that the previous researches of scholars mainly focused on straight pipes, there are few studies on the pipe structure nodes in liquefied soil. The mechanical properties of the three-way pipe structure in the soil liquefaction zone are analyzed by the finite element method (FEM). The influence of pipe diameter, wall thickness, liquefied soil density, transition zone length, buried depth, and pipeline internal pressure on the mechanical response of the pipeline is analyzed.

Keywords: Buried pipeline - Liquefied soil - Pasternak model - Pipeline node - Mechanical response


Rutting prediction models for flexible pavement structures: A review of historical and recent developments

Singh, A.K.1 , Sahoo, J.P.2

1 Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
2 Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India

Journal of Traffic and Transportation Engineering, Volume 8, Issue 3, June 2021, Pages 315-338

Abstract: Rutting is the major distress mode in flexible pavements occurring due to the repeated movement of traffic loading. Deformation in the pavements comprise of both recoverable (elastic) and irrecoverable (plastic) part. Overall deformation occurring in the flexible pavement system due to continuous vehicular movement is contributed from all the components of pavement. A number of empirical models have been proposed by several researchers for analysis and prediction of accumulated rutting in different components of pavement. The accumulated permanent strain has been expressed as the function of the number of load applications and deviator stress applications in most of the models proposed; however, factors such as stress state, moisture content, material type and environmental conditions also impose a significant influence on the permanent deformation characteristics of pavement materials under cyclic loading. In this article, a comprehensive review has been carried out covering every aspect of deformation related to distress occurring in pavements. Important rut models, modeling approaches and modern concepts in the rutting analysis of pavement structures have been presented. In addition to review, fallacy existing in the current design practices related to adaptation of stiffness parameters and negligence of shear strength aspect of subgrade soil has been also presented with the support of literatures.

Keywords: Road engineering - Permanent deformation - Rutting models - Resilient modulus - Shear strength


Venous Biomechanics of Angioplasty and Stent Placement: Implications of the Poisson Effect

Li, N.1 , Mendoza, F.2,3 , Rugonyi, S.2, Farsad, K.1, Kaufman, J.A.1 , Jahangiri, Y.1 , Uchida, B.T.1, Bonsignore, C.4, Al-Hakim, R.1

1 Dotter Interventional Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239, United States
2 Department of Biomedical Engineering, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239, United States
3 Department of Biomedical Engineering, Oregon State University, Corvallis, OR, United States
4 Confluent Medical Technologies, Scottsdale, AZ, United States

Journal of Vascular and Interventional Radiology, Volume 31, Issue 8, August 2020, Pages 1348-1356

Abstract: Purpose: To characterize the Poisson effect in response to angioplasty and stent placement in veins and identify potential implications for guiding future venous-specific device design. Materials and Methods: In vivo angioplasty and stent placement were performed in 3 adult swine by using an established venous stenosis model. Iron particle endothelium labeling was performed for real-time fluoroscopic tracking of the vessel wall during intervention. A finite-element computational model of a vessel was created with ADINA software (version 9.5) with arterial and venous biomechanical properties obtained from the literature to compare the response to radial expansion. Results: In vivo angioplasty and stent placement in a venous stenosis animal model with iron particle endothelium labeling demonstrated longitudinal foreshortening that correlated with distance from the center of the balloon (R2 = 0.87) as well as adjacent segment narrowing that correlated with the increase in diameter of the treated stenotic segment (R2 = 0.89). Finite-element computational analysis demonstrated increased Poisson effect in veins relative to arteries (linear regression coefficient slope comparison, arterial slope 0.033, R2 = 0.9789; venous slope 0.204, R2 = 0.9975; P < .0001) as a result of greater longitudinal Young modulus in veins compared with arteries. Conclusions: Clinically observed adjacent segment narrowing during venous angioplasty and stent placement is a result of the Poisson effect, with redistribution of radially applied force to the longitudinal direction. The Poisson effect is increased in veins relative to arteries as a result of unique venous biomechanical properties, which may be relevant to consider in the design of future venous interventional devices.

Keywords: May-Thurner Syndrome - Iliac Vein - Blood Clot Lysis


Numerical Evaluation of the Knee Arthrodesis Using a Modified External Fixator

Neto, M.A.1,2 , Roseiro, L.M.2,3 , Paulino, M.F.1,2, Amaro, A.M.1,2

1 Mechanical Engineering Department, Coimbra University, Coimbra, Portugal
2 CEMMPRE, Department of Mechanical Engineering, University of Coimbra, Coimbra, Portugal
3 Coimbra Polytechnic - ISEC, Coimbra, Portugal

IFMBE Proceedings, Volume 76, 2020, Pages 1441-1445

Abstract: This work presents the numerical results of arthrodesis using a modified bilateral-monoplanar external fixator for the treatment of septic sequelae of the knee joint. The knee arthrodesis serves as an option of salvage treatment for failed total knee arthroplasty procedures [1]. The arthrodesis technique used in this work was promoted with external fixation consisting on the union of two or more femoral pins with two or more tibial pins through bended lateral bars. Biplanar fixation has higher sagittal stability and higher fusion rates than the monoplanar fixation, but the level of compression on the fusion area as well as the extension of contact area can have a great impact on the bone union. Hence, the main purpose of this work is to give the surgeons additional information on how to influence positively the knee arthrodesis, namely relatively to the fixation level, the homogeneity of contact and to the compression level, but also about some possible complications. The arthrodesis technique was implemented using the CAD Solidworks® software and the numerical analysis was carried out on ADINA® software. With this methodology it was possible to recreate the mechanical procedure of the knee arthrodesis and the results indicate that the arthrodesis technique is not only influenced by the parameters associated with the kind of externatal fixator used, but also with the type of supported used to perform the external fixation assembly.

Keywords: Arthrodesis - Finite element method - Knee


FE modeling of continuous fiber reinforced thermoplastic composite structures produced by additive manufacturing

Majko, J., Sága, M., Vaško, M., Handrik, M., Ságová, Z.

Faculty of Mechanical Engineering, University of Žilina, Univerzitná 8215/1, Žilina, 010 26, Slovakia

IOP Conference Series: Materials Science and Engineering, Volume 776, Issue 1, 1 April 2020, Article number 012080

Abstract: Additive manufacturing is process of joining material, bringing many benefits such as customization and low production cost. Markforged developed Continuous fiber fabrication technology, which allows to print continuous fiber reinforced thermoplastic (CFRTP) composites. Although printed CFRTP parts achieve mechanical properties better than another 3D printed counterparts, there is demand to gain suitable mechanical properties comparable with conventionally manufactured parts using improvements in printing parameters and fiber deposition. In this paper, the main goal is analyzing of geometry constraints of fiber deposition and modeling options in FEM program ADINA. Additionally, stress distribution analysis with regard to stresses in matrix and fibers will be performed.

Keywords: Fused Deposition Modeling - Frequency Division Multiplexing - 3D Printers


Mechanical optimization of a novel hollow traveling wave rotary ultrasonic motor

Ren, W.1 , Yang, M.2, , Chen, L.1, Ma, C.1, Yang, L.1

1 State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing, China
2 Nuaa Super Control Technology Co., Ltd, Nanjing, China

Journal of Intelligent Material Systems and Structures, Volume 31, Issue 8, 1 May 2020, Pages 1091-1100

Abstract: A novel hollow type of traveling wave rotary ultrasonic motor is proposed, optimized, fabricated, and tested in this study. Unlike conventional ultrasonic motors, this novel ultrasonic motor adopts a bran-new preloading method that preload is applied from the bottom of the stator through a wave spring, which can not only enhance the anti-overload ability but also extend the working life of the motor. According to this motor, a three-dimensional finite element model has been built by the commercial finite element software ADINA. In terms of the friction material and the preload, a detailed further optimization procedure is given after the initial design. Finally, the appropriate size and location of the friction layer and a proper preload for this motor have been determined. Almost all of the motor’s mechanical capacities, such as rotational speed, torque, and deformation, can be obtained by simulations in ADINA, which have good agreement with experimental results.

Keywords: ADINA - Friction material- hollow - mechanical optimization - Traveling wave - Ultrasonic motors


An analysis of implicit time integration schemes for wave propagations

Kwon, S.B.1 , Bathe, K.J.2 , Noh, G.3

1 Hyundai Heavy Industries, Ulsan 44032, Republic of Korea
2 Massachusetts Institute of Technology, Cambridge, MA 02139, USA
3 Kyungpook National University, Daegu 41566, Republic of Korea

Computers and Structures, Volume 230, 1 April 2020, Article number 106188

Abstract: The objective of this paper is to investigate the optimal use of some time integration schemes for the solution of transient wave propagation problems. We study the accuracy characteristics of the trapezoidal rule and the ρ-Bathe scheme considering various parameter sets (ρ, γ, CFL) with both consistent and lumped mass matrices. The ρ-Bathe scheme includes also the standard-, β12-Bathe methods, the Newmark method and the trapezoidal rule. The study of the numerical dispersion shows that in the case of the consistent mass matrix, the ρ-Bathe scheme with a proper setting of (ρ, γ) and standard Bathe scheme provide similar dispersion errors and outperform the trapezoidal rule. The optimal CFL number of the ρ-Bathe scheme is about 25% larger than for the standard Bathe scheme. In addition, we show that using a lumped mass matrix and proper values of ρ < 0, γ and CFL in the ρ-Bathe scheme, more accurate solutions can be obtained in some analyses.

Keywords: Wave propagations - Finite elements - Direct time integrations - Implicit schemes - Trapezoidal rule, Newmark and Bathe methods - Numerical dispersion


Sheet metal forming analysis using a large strain anisotropic multiplicative plasticity formulation, based on elastic correctors, which preserves the structure of the infinitesimal theory

Sanz, M.A.1 , Nguyen, K.1 , Latorre, M.2, Rodríguez, M.1 , Montáns, F.J.1

1 Escuela Técnica Superior de Ingeniería Aeronáutica y del Espacio, Universidad Politécnica de Madrid, Pza. Cardenal Cisneros, Madrid, 28040, Spain
2 Department of Biomedical Engineering, Yale University, New Heaven, United States

Finite Elements in Analysis and Design, Volume 164, 15 October 2019, Pages 1-17

Abstract: Sheet metal forming is a very important process in industry to create a wide variety of goods. The analysis of local ductility and residual stresses is important both to assess the viability of the manufacturing process and the reliability of the resulting elements in service. An example is crash-worthiness, where remaining ductility and residual stresses govern the safety of the overall structure during the impact. A main ingredient of finite element simulations for sheet metal forming in industry is a robust continuum-based computational algorithm for large strain elastoplasticity which includes both elastic and plastic anisotropy, as well as mixed hardening. The theory should use exactly-integrable (conservative) elastic and hardening behaviors based on physically motivated proper state variables and, if possible, result in a simple integration algorithm. In this work we implement a novel large strain formulation for anisotropic hyperelasto-plasticity in a user subroutine of the commercial program ADINA to perform sheet metal forming simulations, testing the robustness and suitability of the model for industry, as well as its accuracy. The formulation is based on a new approach to the treatment of large strain kinematics, using logarithmic elastic corrector rates instead of plastic rates. Furthermore, kinematic hardening is formulated without an explicit backstress. We compare and discuss the results with those in the literature which use alternative frameworks.

Keywords: Anisotropic plasticity - Hill plasticity - Large strains - Logarithmic strains - Multiplicative decomposition - Sheet metal forming


Free vibration and buckling of tapered columns made of axially functionally graded materials

Lee, J.K.1 , Lee, B.K.2

1 Department of Civil Engineering, University of Seoul, 163 Seoulsiripdae-ro, Dongdaemun-gu, Seoul 02504, South Korea
2 Department of Civil and Environmental Engineering, Wonkwang University, 460 Iksan-daero, Iksan-si, Jeollabuk-do 54538, South Korea

Applied Mathematical Modelling, Volume 75, November 2019, Pages 73-87

Abstract: This paper presents a unified model to analyze the free vibration and buckling of axially functionally graded Euler-Bernoulli columns subjected to an axial compressive force. The material properties vary linearly along the longitudinal direction, and column with circular and square cross sections is linearly tapered. The governing differential equations of the problem are derived and solved using the direct integral method combined with the determinant search technique. The computed results are compared with those reported in the literature and obtained from the finite element software ADINA. Numerical examples for natural frequency, buckling load and their corresponding mode shapes are given to highlight the effects of modular ratio, taper ratio and cross sectional shape as well as the end condition.

Keywords: Axially functionally graded material - Buckling - Free vibration - Tapered column


On blowdown analysis with efficient and reliable direct time integration methods for wave propagation and fluid-structure-interaction response

Nilsson, K.1 , Tornberg, F.2

1 Hifi Engineering, Månsagårdsvägen 12, 439 36 Onsala, Sweden
2Onsala Ingenjörsbyrå AB, Energigatan 4, 434 37 Kungsbacka, Sweden

Computers & Structures, Volume 216, May 2019, Pages 1-14


In literature time integration methods are described separately for wave propagation or structural dynamic problems. In this paper we focus on implicit methods for problems that involve simultaneous wave propagation and strong fluid-structure-interaction response. As example we show methods and models for nuclear pressure vessel blowdown analysis.

We present validation against measurements from literature for three different ways to perform this analysis. These are: 2-way iterative fluid-structure-interaction (FSI) between CFD and FE codes, direct 2-way FSI in the FE code and sequential 1+2-way FSI. The CFD and FE codes provide different time integration methods. Here we investigate the trapezoidal and composite methods, in the FE code the Bathe method.

We show that the selected validation problem is linear and follows the principle of superposition and can be solved with the all-linear fluid-structure FE model, with the trapezoidal rule for computational efficiency.

On the contrary, in applied analyses of reactor pressure vessels structural non-linearities must often be included, such as contact, friction stick-slip and plasticity. We show that for non-linear fluid-structure FE models the Bathe method is efficient and reliable. The Bathe method provides high accuracy in both the wave propagation and the fluid-structure-interaction response.

Keywords: Fluid structure interaction - Wave propagation - Implicit time integration - Bathe method - Potential based fluid - Nonlinear structural dynamics


Analysis of heat flow in composite structures used in window installation

Adamus, J., Pomada, M.

Czestochowa University of Technology, 69 Dabrowskiego St., Czestochowa, 42-201, Poland

Composite Structures, Volume 202, 15 October 2018, Pages 127-135

Abstract: In the paper, the influence of sill beam material and its construction on heat flow through an external wall with a window was analysed. Such beams are used as the support elements in window installation in the thermal insulation layer. The beams were made of fibre-reinforced polyurethane composites. Some of them were reinforced with metal profiles. Taking into consideration the material properties such as specific strength, heat transfer coefficient and corrosion resistance, in addition to typical steel materials, reinforcements made of aluminium and titanium alloys were also analysed. Numerical calculations were performed with the ADINA System, which is based on the finite element method (FEM). The process of heat exchange between the interior with the constant temperature of 20 °C and the external environment with the temperature of −20 °C was simulated. Temperature distribution in the wall as well as the course of the 0° isotherm and the possibility of condensation in the wall were analysed. Moreover, corrosion and the economic aspects connected with the application of metal profiles used as reinforcements were taken into consideration. The numerical model for the sill beam without reinforcement was verified in experiments.

Keywords: Heat transfer - Metal reinforcement - Numerical analysis - Warm installation - Window installation


Numerical modal analysis for vibration-damping properties of ductile cast

Kováčiková, P., Vavro, J., Dubec, A.

Department of Numerical Methods and Computational Modeling, Faculty of Industrial Technologies, Alexander Dubcek University of Trencin, I. Krasku 491/30, Púchov, 020 01, Slovakia

MATEC Web of Conferences: Volume 157, 14 March 2018, Article number 02019

Abstract: This paper deals with standard test method for the measurement of vibration-damping properties of materials, ductile cast iron-graphitic cast iron with the spherical shape of graphite (ductile cast iron). Investigation is focused on its mechanical properties, chemical composition and microstructure, which are necessary as input parameters for computational modeling and numerical analysis. The vibration or oscillating of experimental samples are closely connected with such parameters as natural shapes (eigenshapes) and natural frequencies (eigenfrequencies). Preparation of a geometric model of a homogeneous beam sample and numerical analysis was performed by finite element method in the ADINA software environment. This paper can be used for further development and growth from the aspect of application of computational tools in the area of damping and eigenfrequency properties for construction materials.

Keywords: ADINA - Cast iron - Eigenfrequencies - Eigenshapes - Finite elements methods - Graphite


Comparison of steel-concrete composite column and steel column

Lacki, P., Derlatka, A., Kasza, P.

Czestochowa University of Technology, Dąbrowskiego 69, Częstochowa, 42-201, Poland

Composite Structures: Volume 202, 15 October 2018, Pages 82-88

Abstract: 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.

Keywords: FEM - Steel - Steel reinforced concrete column - Steel-concrete composite column


Numerical study of the blockage length effect on the transient wave in pipe flows

Zhao, M.1, Ghidaoui, M.S.2, Louati, M.3, Duan, H.-F.4

1 Department of Engineering Mechanics, Dalian University of Technology, Dalian, China
2 Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong
3 Post-doctoral Fellow, Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong
4 Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong

Journal of Hydraulic Research: Volume 56, Issue 2, 4 March 2018, Pages 245-255

Abstract: 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 turbulent flow problem with complex geometry. Two-dimensional axisymmetric computational results are validated by several examples. In practice, the water hammer wave generated by rapid valve closure usually exhibits wave front smearing. The numerical analysis shows that for a blockage length larger than the wave front thickness, the magnitude of the incident wave may be significantly suppressed as a result of the interaction between the blockage and the wave front. By reflecting negative pressure waves toward the incident wave before its maximum pressure arrives at the blockage, the maximum transient pressure may be considerably reduced. Consequently, the blockage behaves as a discrete blockage. However, if the blockage length is large compared with the thickness of the wave front, the incident wave conserves its initial amplitude, and the blockage behaves as an extended blockage. Therefore, the occurrences of discrete and extended blockages depend on the thickness of the wave front and thus on the rapidity of the manoeuvre that generates the transient.

Keywords: Blockage - computational fluid dynamics - numerical diffusion - transient - water pipeline - wave


Numerical simulation of one-way concrete slabs reinforced with glass fiber reinforced polymer bars under service temperatures

Lardjane, S.1, Bellakehal, H.1, Zaidi, A.1, Masmoudi, R.2

1 Structures Rehabilitation and Materials Laboratory (SREML), University of Laghouat, Algeria
2 Department of Civil Engineering, University of Sherbrooke, Canada

Canadian Journal of Civil Engineering: Volume 45, Issue 10, 2018, Pages 878-888

Abstract: 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 (∆Tcr) varied between 15°C and 30°C. While, the circumferential cracks appear within concrete, at FRP bar – concrete interface, at ∆Tcr 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 f ct = 1.9 to 2.9 MPa. Nevertheless, for high temperatures, the splitting failure of concrete cover is produced at thermal loads ∆Tsp' varied from 30°C to 59°C. While, for concrete situated between GFRP bars, the splitting failure occurred at thermal loads ∆T sp ' 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.

Keywords: Concrete slabs - Cracking thermal loads - Glass fiber reinforced polymer (GFRP) bars - Numerical model - Thermal stresses and strains


Seismic response of base-isolated CRLSS considering nonlinear elasticity of concrete

Cheng, X., Ma, L., Zhang, A., Liu, B.

School of Civil Engineering, Lanzhou University of Technology, China

Journal of Asian Architecture and Building Engineering: Volume 17, Issue 3, 2018, Pages 533-540

Abstract: The purpose of this paper is to study the seismic response of a base-isolated, concrete rectangular liquid-storage structure (CRLSS) under small-amplitude sloshing. In this study, the three-dimensional FEM of the base isolated CRLSS is established by using ADINA. The concrete material is assumed to be nonlinear and elastic, and the criterion for the small amplitude sloshing is defined to determine the seismic response of a base-isolated CRLSS under different conditions. The results show that when small-amplitude sloshing occurs and the nonlinear elasticity of the concrete material is considered, the displacement of wallboard, the height of liquid sloshing and the equivalent stress are increased with the increase in the earthquake intensity when comparing the same liquid height and different intensities of a bidirectional earthquake. The liquid height is found to affect the seismic response of the base-isolated CRLSS. The lower the liquid height is, the larger the equivalent stress is, and the greater the displacement of the wallboard and the amplitude of the liquid sloshing are.

Keywords: Concrete - Liquid-solid interaction - Nonlinear elasticity - Rectangular liquid-storage structure - Seismic response


Tuned mass damper system of high-rise intake towers optimized by improved harmony search algorithm

Li, D.1,2,3, Chen, J.2, Zhou, Y.3

1 Faculty of Civil and Architecture Engineering, East China Institute of Technology, Nanchang, 330013, China
2 School of Civil Engineering, Fujian University of Technology, Fuzhou, 350108, China
3School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan, 232001, China

Advances in Materials Science and Engineering: Volume 2018, 2018, Article number 7458696

Abstract: Artificial frozen soil is a kind of typical creep material, and the frozen clay under the unloading stress paths of high-confining pressure conforms to the improved the Zienkiewicz-Pande parabola-type yield criterion, and the Mohr-Coulomb yield function can describe the shear yield surface of artificial frozen clay under low-confining pressure. Based on the results of triaxial creep and shear tests for artificial frozen soil, the viscoplastic damage variable and evolution rule of artificial frozen clay were obtained by using the theory of viscoelastic-plastic mechanics and damage mechanics. An improved Zienkiewicz-Pande parabola-type yield criterion was used instead of a linear Newton body to obtain a coupled constitutive model of viscoelastic-plastic damage in the frozen soil under the unloading stress paths and to derive the coupling flexibility matrix for viscoelastic and viscoplastic damage. A finite element program of artificial frozen soil considering creep damage was written in the Visual Fortran 6.6A environment and embedded into the nonlinear finite element software ADINA as a user subroutine. The results of numerical simulation and laboratory testing were identical, with a maximum error of no more than 4.8%. This work shows that it is reasonable to describe the creep constitutive model of frozen soil with the viscoelastic-plastic-coupled constitutive model.


Measuring of vibration-damping properties of cast iron

Kováčiková, P., Vavro, J., Jr., Dubec, A.

Faculty of Industrial Technologies in Púchov, Alexander Dubček University of Trenčín, I. Krasku 491/30, Púchov, 020 01, Slovakia

Manufacturing Technology: Volume 18, Issue 1, 2018, Pages 57-59

Abstract: Nowadays, ever increasing demands are being made on equipment and machine structures. This fact negatively affects their lifespan, reliability and security. Internal damping is caused by material malfunctions in the microstructure, thermoelastic effects, movement of dislocations or the effects of swirling currents. This paper deals with microstructure, chemical composition and mechanical properties of ductile iron. These data are required as input parameters for computational modeling and numerical analysis. The numerical part is focused on the modal analysis of the homogeneous beam sample by finite element method in the ADINA software environment.

Keywords: Cast iron - Finite element methods - Mechanical properties - Microstructure


Experimental and Numerical Studies on Sloshing Dynamics of PCS Water Tank of Nuclear Island Building

Li, X.1,2, Song, C.1, Zhou, G.3, Wei, C.3, Lu, M.4

1 College of Architecture and Civil Engineering, Beijing University of Technology, Beijing, 100124, China
2 Institute of Geophysics, China Earthquake Administration, Beijing, 100081, China
3 Nuclear and Radiation Safety Center, Ministry of Environmental Protection of the People's Republic of China, Beijing, 100082, China
4 Institute of Crustal Dynamics, China Earthquake Administration, Beijing, 100085, China

Science and Technology of Nuclear Installations: Volume 2018, 2018, Article number 5094810

Abstract: Water tank is one important component of passive containment cooling system (PCS) of nuclear island building. The sloshing frequency of water is much less than structure frequency and large-amplitude sloshing occurs easily when subjected to seismic loadings. Therefore, the sloshing dynamics and fluid-structure interaction (FSI) effect of water tank should be considered when the dynamic response of nuclear island building is analyzed. A 1/16 scaled model was designed and the shaking table test was done, in which the hydrodynamic pressure time histories and attenuation data of wave height were recorded. Then the sloshing frequencies and 1st sloshing damping ratio were recognized. Moreover, modal analysis and time history analysis of numerical model were done by ADINA software. By comparing the sloshing frequencies and hydrodynamic pressures, it is proved that the test method is reasonable and the formulation of potential-based fluid elements (PBFE) can be used to simulate FSI effect of nuclear island building.


Dynamical analysis of steel point connectors used for fixation of glass façades

Major, I., Major, M., Respondek, Z.

Czestochowa university of technology, Faculty of civil engineering, 3 Akademicka str., Częstochowa, 42-200, Poland

Archives of Metallurgy and Materials: Volume 63, Issue 1, 2018, Pages 491-496

Abstract: This study presents the numerical comparative analysis of the point connector and its modification used for fixation of glass façades in terms of the obtained values of stresses and displacements. Since the most popular components of glass façades are square, rectangular or triangular, it was adopted that the load to the connectors is transferred from a rectangular façade component. Furthermore, the dynamic effect of wind gusts on façades was also assumed, with both wind pressure and wind suction. Adoption of the rectangular component of the glass façade leads to an unfavourable load distribution observed in the location of the connection, with the connector additionally twisted with respect to its own symmetry axis. ADINA software, based entirely on the finite elements method, was used for numerical analysis. The examinations allowed for evaluation of how the modifications introduced into the referential model reduce values of the obtained stresses and displacements.

Keywords: ADINA - Dynamics - Glass façades - Point connector - Wind load


A posteriori error estimation for incompressible viscous fluid with a new boundary condition

El Akkad, A.1, Elkhalfi, A.2

1 Département de mathématiques, Centre Régional des Métiers d'Education et de Formation de Fès (CRMEF Fès), Rue de Koweit, Ville: Fès, Morocco
2 Laboratoire Génie Mécanique, Faculté des Sciences et Techniques, Route d'Imouzzer - Fès, Morocco

Boletim da Sociedade Paranaense de Matematica, Volume 36, Issue 3, 2018, Pages 53-74

Abstract: This paper describes numerical solutions of incompressible Navier-Stokes equations with a new boundary condition. To solve this problem, we use the discretization by mixed finite element method. We use a vector extrapolation method for computing numerical solutions of the steady-state Navier-Stokes equations. In addition, two types of a posteriori error indicator are introduced and are shown to give global error estimates that are equivalent to the true error. A numerical experiment on the driven cavity flow is given to demonstrate the effectiveness of the vector extrapolation method. We compare the result with the solution from commercial code like ADINA system as well as with values from other simulations.

Keywords: A posteriori error estimation - ADINA system - Finite Element Method - Navier-Stokes Equations - Vector extrapolation


Analysis of stress field in a single anisotropic diamond/square shaped inclusion using the volume integral equation method and the numerical equivalent inclusion method

Lee, J.1, Nozaki, H.2, Lee, H.3

1 Department of Mechanical and Design Engineering, Hongik University, Sejong, South Korea
2 College of Education, Ibaraki University, Mito, Japan
3 College of Liberal Studies, Seoul National University, Seoul, South Korea

Composite Interfaces, Volume 25, Issue 3, 4 March 2018, Pages 221-249

Abstract: A volume integral equation method (VIEM) is used to study elastostatic problems in an unbounded elastic solid containing a single diamond/square shaped inclusion subject to uniform tensile stress at infinity. The inclusion is assumed to be a long parallel diamond/square cylinder composed of isotropic or anisotropic elastic materials and perfectly bonded to the isotropic matrix. The solid is assumed to be under plane strain on the plane normal to the cylinder. A detailed analysis of the stress field at the interface between the isotropic matrix and the single isotropic/orthotropic diamond/square shaped inclusion is carried out. The effects of a single isotropic/orthotropic diamond/square shaped inclusion on the stress field at the interface between the matrix and the inclusion are investigated in detail. The accuracy of the volume integral equation method for the interfacial stress field is validated and compared by the numerical equivalent inclusion method (NEIM) and the finite element method (FEM) using ADINA. Through detailed analysis of plane elastostatic problems using the parallel volume integral equation method (PVIEM) in an unbounded isotropic matrix with multiple isotropic diamond shaped inclusions under uniform remote tensile loading, it is demonstrated that the volume integral equation method can also be applied to solve general two- and three-dimensional elastostatic problems involving multiple isotropic/anisotropic inclusions whose shape and number are arbitrary.

Keywords: anisotropic inclusion - diamond/square shaped inclusion - finite element method - numerical equivalent inclusion method - Volume integral equation method


Layer-wise numerical model for laminated glass plates with viscoelastic interlayer

Zemanová, A., Zeman, J., Janda, T., Šejnoha, M.

Department of Mechanics, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, Prague 6, 166 29, Czech Republic

Structural Engineering and Mechanics, Volume 65, Issue 4, 25 February 2018, Pages 369-380

Abstract: In this paper, a multi-layered finite element model for laminated glass plates is introduced. A layer-wise theory is applied to the analysis of laminated glass due to the combination of stiff and soft layers; the independent layers are connected via Lagrange multipliers. The von Kármán large deflection plate theory and the constant Poisson ratio for constitutive equations are assumed to capture the possible effects of geometric nonlinearity and the time/temperature-dependent response of the plastic foil. The linear viscoelastic behavior of a polymer foil is included by the generalized Maxwell model. The proposed layer-wise model was implemented into the MATLAB code and verified against detailed three-dimensional models in ADINA solver using different hexahedral finite elements. The effects of temperature, load duration, and creep/relaxation are demonstrated by examples.

Keywords: Finite element method - Generalized Maxwell model - Geometric nonlinearityLagrange multipliers - Laminated glass plate - Layer-wise plate model - Newton method - Time/temperature-dependent behavior - Von Kármán assumptions - Williams-Landel-Ferry equation


Finite element modelling of reinforced road pavements with geogrids

Neves, J.1, Gonçalves, M.2

1 CERIS, CESUR, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
2 Infraestruturas de Portugal, Lisboa, Portugal

Numerical methods in geotechnical engineering IX, Volume 2, 2018, Pages 1371-1376

Abstract: Finite Element Modelling (FEM) is one of the most common methods used to solve complex problems in civil engineering. The aim of this paper is to demonstrate the use of FEM to analyse the reinforcing influence of geogrids in road pavements. Using ADINA software, a parametric study was carried out, taking into consideration diverse pavement structures, climatic and traffic conditions, and geogrid reinforcement solutions. The paper describes the two-dimensional axisymmetric finite element model developed for unreinforced and reinforced pavement analysis. In general, the research confirmed the adequacy of ADINA for the analysis of reinforced road pavements that use geogrids. Results from the numerical analysis allowed for the following main conclusions: 1) fatigue resistance was improved when the geogrid was applied on top of unbound granular layers; 2) rutting decreased when the geogrid was applied on top of the subgrade soil.


A Fluid-Structure Interaction case study on a square sail in a wind tunnel

Ghelardi, S.1, Freda, A.2, Rizzo, C.M.1, Villa, D.1

1 DITEN - Polo Navale, Università degli Studi di Genova, via Montallegro 1, Genova, I-16145, Italy
2 DICCA - Dipartimento di Ingegneria Civile, Chimica e Ambientale, via Montallegro 1, Genova, I-16145, Italy

Ocean Engineering, Volume 163, 1 September 2018, Pages 136-147

Abstract: A Fluid-Structure Interaction (FSI) conventional case study is proposed to be used as a benchmark for numerical analyses. Experimental tests were carried out to provide targets for comparisons; in particular, the study regarded the estimate of the deformed configuration (“flying shape” in the sailing field) of a square sail under a uniform flow regime in a wind tunnel facility. Several tests have been carried out at different wind velocities. The sailcloth has been characterized by means of mono-axial tensile tests obtaining Young's and shear moduli as well as Poisson's coefficients, which have then been used as input parameters for numerical analyses. Test results are considered a benchmark target deserving challenging aspects for numerical simulations in spite of the selected simple test geometry and conditions. Numerical tests have been carried out by means of a commercial software (ADINA™). Analyses used a strongly coupled partitioned approach between a Finite Volume Method (FVM) based on Reynolds Averaged Navier Stokes (RANS) equations, whereas a Finite Element Method (FEM) has been adopted for the structural field. A comparison has been eventually carried out assessing different numerical models. A good overall agreement between experimental and numerical results has been obtained by suitably setting FSI simulation algorithms.

Keywords: Benchmark - CFD - FEA - Fluid structure interaction (FSI) - Sail - Wind tunnel


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