Publications

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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)

To Download — Second Edition of the Book "Finite Element Procedures" (6th printing)

You are welcome to download the second edition of the book, 6th printing, however, please note that the book is copyrighted and should only be used in the same manner as a purchased hard-copy of the book.

Improved versions will be made available here, from time to time, as the 7th printing, and so on.

"Finite Element Procedures", 2nd Edition (.pdf)

Solutions to exercises in the book "Finite Element Procedures", 2nd Edition, 2014 are given in this manual (.pdf)

The Chinese translation of the 2nd edition is also available: Vol. 1 Vol. 2


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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Seismic performance numerical simulation analysis of LNG storage tank with filled wall

Li, J.1, Sun, J.2, Cui, L.2, Wang, X.3, Hao, J.3

1 China Huanqiu Contracting and Engineering Cooperation, Beijing 100012, China
2 College of Civil and Architecture Engineering, Dalian Nationalities University, Dalian 116600, China
3 College of Civil and Architecture Engineering, Northeast Petroleum University, Daqing 163318, China

Journal of Earthquake Engineering and Engineering Vibration: Volume 34, Issue 3, June 2014, Pages 157-164

Abstract: To study pile-soil, filled wall and inner tank and outer tank interaction effect on seismic responsees of 16 × 104 m3 full-containment LNG tanks, pile-soil and filled wall use spring damper element, prestressed concrete outer tank uses 3D solid element, inner tank uses shell element, and fluid uses potential flow element, based on ADINA, three-dimensional finite element model is established. Peak acceleration 0. 34g El Centro ground motion is adopted to analyze seismic response by using Newmark numerical integration method, and it is compared with the theory solution. The results show that:filled wall between inner tank and outer tank could reduce seismic response, but has little effect on the sloshing height; finite element solutions are compared with the theoreticat solutions; base shear and base bending moment are coincident; sloshing height is less than the theoretical solution. From actual conditions, the finite element solution is feasible. On the safe side,the filled wall may be ignored in seismic design of LNG storage tank.

Keywords: ADINA - Filled wall - LNG tanks - Seimic response

 

CFD-based thrust analysis of unmanned aerial vehicle in hover mode: Effects of single rotor blade shape

Yun, J.H.1, Choi, H.-Y.2, Lee, J.1

1 School of Mechanical Engineering, Yonsei Univ., South Korea
2 Dept. of Mechanical Engineering, Dongyang Mirae Univ., South Korea

Transactions of the Korean Society of Mechanical Engineers, A: Volume 38, Issue 5, May 2014, Pages 513-520

Abstract: An unmanned aerial vehicle (UAV) should be designed to be as small and lightweight as possible to optimize the efficiency of changing the blade shape to enhance the aerodynamic performance, such as the thrust and power. In this study, a computational fluid dynamics (CFD) simulation of an unmanned multi-rotor aerial vehicle in hover mode was performed to explore the thrust performance in terms of the blade rotational speed and blade shape parameters (i.e., taper ratio and twist angle). The commercial ADINA-CFD program was used to generate the CFD data, and the results were compared with those obtained from blade element theory (BET). The results showed that changes in the blade shape clearly affect the aerodynamic thrust of a U AV rotor blade.

Keywords: Blade element theory - Blade parameters - Computational fluid dynamics simulation - Hovering - Multi-rotor unmanned aerial vehicle - Thrust

 

Real-time estimation of the structural response using limited measured data

Sedarat, H.1, Talebinejad, I.1, Emami-Naeini, A.1, Falck, D.1, Van Der Linden, G.1, Nobari, F.1, Krimotat, A.1, Lynch, J.2

1 SC Solutions, 1261 Oakmead Pkwy, Sunnyvale, CA 94085, United States
2 University of Michigan, G. Brown Building, Ann Arbor, MI 48109-2125, United States

Proceedings of SPIE - The International Society for Optical Engineering: Volume 9063, 2014, Article number 906311

Abstract: This study introduces an efficient procedure to estimate the structural response of a suspension bridge in real-time based on a limited set of measured data. Unlike conventional techniques, the proposed procedure does not employ mode shapes and frequencies. In this study, the proposed technique is used to estimate the response of a suspension bridge structure based on a set of strain gauge measurements. Finite element analysis is performed only once to set up the structural parameters, namely computed flexibility matrix, and computed hanger forces matrix. The response of the bridge was estimated without any additional finite element analysis using the computed structural parameters and the measured hanger strains. The Alfred Zampa Memorial Bridge, on Interstate 80 in California, was selected for this study. A high fidelity finite element model of the bridge was developed using the general purpose computer program ADINA. The proposed method has been proven to have the capability to estimate any type of structural response in real time based on the measured hanger strains, and provides an important part of an integrated Structure Health Monitoring (SHM) system for major bridges.

Keywords: Alfred Zampa Memorial Bridge - Finite element - Real-time response - SHM - Suspension bridges

 

Study on the thermal-stress couple field of nuclear power pump mechanical seal based on ADINA

Zhang, H.Y.1, Zhu, W.B.1, Zhou, G.1, Hao, X.2

1 School of Mechanical Engineering and Automation, Xihua University, Chengdu, China
2 The Design Department of the Fourth Plant of YTO Group, China

Advanced Materials Research: Volume 971-973, 2014, Pages 1160-1164

Abstract: In this paper, a two-dimensional axisymmetric thermal-stress coupling model of mechanical seal's rotator and stator components was established by ADINA, simplification and appropriate boundary constrained condition of stator and rotator was obtained by analyzing the contact state among the seal rings. It's shown that the contact surface is equivalent to a resource of constant thermal, temperature of contact surface rises step by step and the location of the maximum temperature getting close to the midpoint within the contact surface according to the sliding time, the temperature gradient decrease along the worksheet so that the temperature decrease accordingly in a parabolic isogram.

Keywords: ADINA - Mechanical seal - Nuclear reactor coolant pump (NNCP) - Thermal-stress coupling

 

Numerical simulation of mining overburden and surface deformation law

Zhao, D.S., Guo, D.L.

Key Laboratory of Liaoning Province for Prediction and Control on Complicated Structure System, Dalian University, Dalian 116622, China

Advanced Materials Research: Volume 962-965, 2014, Pages 1066-1069

In order to obtain overburden and surface deformation law, this paper takes S2S9 working face fully-mechanized mining of certain coal mine for example, uses the finite element ADINA software, and it establishes two-dimensional numerical model, analyzes overburden and surface deformation caused by the working face mining. The study shows the amount of each point movement in the top of the mined-out area gradually decreases from the bottom to up, and the range of surface movement is also increasing with advancement of the coal excavation. After the completion of the working face, it forms a subsidence curve which is symmetry for the maximum vertical point and an antisymmetric horizontal deformation curve. The zero point of horizontal movement is located above the center of mining sector, and the maximum tilt is 2.044 mm/m.

Keywords: Horizontal deformation - Numerical - Overburden - Subsidence - Working face mining

 

Real-time estimation of the structural response using limited measured data

Sedarat, H.1, Talebinejad, I.1, Emami-Naeini, A.1, Falck, D.1, Van Der Linden, G.1, Nobari, F.1, Krimotat, A.1, Lynch, J.2

1 SC Solutions, 1261 Oakmead Pkwy, Sunnyvale, CA 94085, United States
2 University of Michigan, G. Brown Building, Ann Arbor, MI 48109-2125, United States

Proceedings of SPIE - The International Society for Optical Engineering: Volume 9063, 2014, Article number 906311

Abstract: This study introduces an efficient procedure to estimate the structural response of a suspension bridge in real-time based on a limited set of measured data. Unlike conventional techniques, the proposed procedure does not employ mode shapes and frequencies. In this study, the proposed technique is used to estimate the response of a suspension bridge structure based on a set of strain gauge measurements. Finite element analysis is performed only once to set up the structural parameters, namely computed flexibility matrix, and computed hanger forces matrix. The response of the bridge was estimated without any additional finite element analysis using the computed structural parameters and the measured hanger strains. The Alfred Zampa Memorial Bridge, on Interstate 80 in California, was selected for this study. A high fidelity finite element model of the bridge was developed using the general purpose computer program ADINA. The proposed method has been proven to have the capability to estimate any type of structural response in real time based on the measured hanger strains, and provides an important part of an integrated Structure Health Monitoring (SHM) system for major bridges.

Keywords: Alfred Zampa Memorial Bridge - Finite element - Real-time response - SHM - Suspension bridges

 

Computational analysis of cartilage implants based on an interpenetrated polymer network for tissue repairing

Manzano, S.1, 2, 3, Poveda-Reyes, S.4, Ferrer, G.G. 3, 4, Ochoa, I. 1, 2, 3, Hamdy Doweidar, M.1, 2, 3

1 Group of Structural Mechanics and Materials Modelling (GEMM), Aragón Institute of Engineering Research (I3A), University of Zaragoza, Spain
2 Mechanical Engineering Department, School of Engineering and Architecture (EINA), University of Zaragoza, Spain
3 Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Spain
4 Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Valencia, Spain

Computer Methods and Programs in Biomedicine: Volume 116, Issue 3, October 2014, Pages 249-259

Abstract: Interpenetrated polymer networks (IPNs), composed by two independent polymeric networks that spatially interpenetrate, are considered as valuable systems to control permeability and mechanical properties of hydrogels for biomedical applications. Specifically, poly(ethyl acrylate) (PEA)-poly(2-hydroxyethyl acrylate) (PHEA) IPNs have been explored as good hydrogels for mimicking articular cartilage. These lattices are proposed as matrix implants in cartilage damaged areas to avoid the discontinuity in flow uptake preventing its deterioration. The permeability of these implants is a key parameter that influences their success, by affecting oxygen and nutrient transport and removing cellular waste products to healthy cartilage. Experimental try-and-error approaches are mostly used to optimize the composition of such structures. However, computational simulation may offer a more exhaustive tool to test and screen out biomaterials mimicking cartilage, avoiding expensive and time-consuming experimental tests. An accurate and efficient prediction of material's permeability and internal directionality and magnitude of the fluid flow could be highly useful when optimizing biomaterials design processes. Here we present a 3D computational model based on Sussman-Bathe hyperelastic material behaviour. A fluid structure analysis is performed with ADINA software, considering these materials as two phases composites where the solid part is saturated by the fluid. The model is able to simulate the behaviour of three non-biodegradable hydrogel compositions, where percentages of PEA and PHEA are varied. Specifically, the aim of this study is (i) to verify the validity of the Sussman-Bathe material model to simulate the response of the PEA-PHEA biomaterials; (ii) to predict the fluid flux and the permeability of the proposed IPN hydrogels and (iii) to study the material domains where the passage of nutrients and cellular waste products is reduced leading to an inadequate flux distribution in healthy cartilage tissue. The obtained results show how the model predicts the permeability of the PEA-PHEA hydrogels and simulates the internal behaviour of the samples and shows the distribution and quantification of fluid flux.

Keywords: Cartilage-like hydrogels - Computational model - FE simulation - Interpenetrated polymer networks - Sussman-Bathe model

 

Numerical analysis of stress states for graphitic cast iron structures

Vavro, J.1, Vavro, J.1, Kováciková, P.1, Kopas, P.2, Handrik, M.2, Bezdedová, R.1

1 Alexander Dubcek University of Trencín, Slovakia

2 University of Žilina, Slovakia

Applied Mechanics and Materials: Volume 611, 2014, Pages 252-255

Abstract: The presented work is focused on the analysis of stress distribution around the graphitic particles in microstructure of ductile cast iron with the spheroidal shape of graphite (SGCI) and grey cast iron with the lamellar shape of graphite (LGCI). The analysis was made with help of the finite element method in the software system ADINA.v.8.6.2. On the basis of the real structure, the finite element method was used for creation of the model which was subsequently used for calculation of the distribution of stress in the material structure. The input data for numerical analysis were obtained on the basis of evaluation of the structure with help of image analysis. The numerical analysis proved that graphitic particles in the matrix cause the accumulation of stress and the distribution of given stress depends on the shape of the graphitic particles.

Keywords: Cast iron - Ductile cast iron - Finite element method - Grey cast iron - Microstructure - Numerical analysis - Stress

 

Dynamic time-history response of cylindrical tank considering fluid - Structure interaction due to earthquake

Kotrasová, K.1, Grajciar, I.2, Kormaníková, E.1

1 Vysokoškolská 4, 040 01 Košice, Slovakia
2 Ricardo Prague, s.r.o, Czech Republic

Applied Mechanics and Materials: Volume 617, 2014, Pages 66-69

Abstract: Ground-supported cylindrical tanks are used to store a variety of liquids. The fluid was develops a hydrodynamic pressures on walls and bottom of the tank during earthquake. This paper provides dynamic time-history response of concrete open top cylindrical liquid storage tank considering fluid-structure interaction due to earthquake. Numerical model of cylindrical tank was performed by application of the Finite Element Method (FEM) utilizing software ADINA. Arbitrary-Lagrangian-Eulerian (ALE) formulation was used for the problem analysis. Two way Fluid-Structure Interaction (FSI) techniques were used for the simulation of the interaction between the structure and the fluid at the common boundary.

Keywords: Cylindrical tank - Earthquake - FEM - Fluid - structure interaction

 

Ship impact behavior on Jacket type offshore wind turbine foundation

Zhang, J.1, Gao, D.1, Sun, K.2, Zhang, Z.2

1 College of Aerospace and Civil Engineering, Harbin Engineering University, Harbin, China
2 Deepwater Engineering Research Center, Harbin Engineering University, Harbin, China

Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE: Volume 4B, 2014

Abstract: Jacket is an ideal supporting structure for large 4 to 6 MW offshore wind turbine (OWT) in deep sea. However, Due to the harsh marine environment, as well as offshore wind farms are mostly located near a busy waterway, it is inevitable that ships crash offshore wind power structures. Sometimes, collision accidents may result in severe damage in the support structure. To study the collision behavior of jacket offshore structure, dynamic characteristics of the jacket OWT foundation is analyzed in this paper, based on ADINA explicit dynamic analysis method, considering different ship speed, impact locations and joint thickness. Based on the numerical results, the joints are reinforced in special location to meet requirements. Structural performances of jacket type OWT foundation under ship impact are studied. The research results in the paper can provide the reference for practical engineering design.

 

Effective finite element solution and post-processing for wide load spectrum

Handrik, M., Vasko, M., Kopas, P., Saga, M.

Department of Applied Mechanics, Faculty of Mechanical Engineering, University of Zilina, Slovakia

Communications - Scientific Letters of the University of Zilina: Volume 16, Issue 3 a, 2014, Pages 19-26

Abstract: This paper presents a computational algorithm allowing the efficient use of high-performance computing resources to solve nonlinear problems of continuum mechanics using FEM. The algorithm is suitable for solving static problems and tasks of estimating lifetime of structures in cases where the load is defined by the load spectrum. The complexity of the problem increases significantly in the case of nonlinear problems. The principle of the stress superposition cannot be used in that case. For each loading mode a separate FE analysis must be made. A quick and efficient procedure for evaluating the results of mentioned analysis for the static calculation as well as for the estimated life calculation is also presented in this paper. In the presented examples the contact of bodies is used as a source of nonlinearity. The size, shape or position of the contact area is not possible to estimate in contact of bodies. These types of problems are thus highly nonlinear. Programs for the presented algorithms are processed in the program package OCTAVE and calculations using FEM are made in the software ADINA.

Keywords: ADINA - Contact of bodies - FEM - Finite element mesh - Lifetime - OCTAVE - Spectrum of load - State of stress - Static analysis - Stress tensor

 

Numerical analysis of aluminum cellular beams with cells of different arrangement

Derlatka, A. , Kasza, P.

Czȩstochowa University Of Technology, 69 Da̧browskiego Str., 42-201 Czȩstochowa, Poland

Advanced Materials Research: Volume 1020, 2014, Pages 158-164

Abstract: The paper presents a numerical analysis of cellular beams with cells of different arrangement. The ADINA System based on the Finite Element Method (FEM) is used in the calculations. The beams made of 6061-T6 aluminum alloy are analysed. Such beams are used in civil engineering and aircraft industry as load-bearing parts. The beam components are joined by Refill Friction Stir Spot Welding (RFSSW). The I-profile beams with cell diameter of 62 mm are analysed. The beam length is 0.8 m and its cross section is 50x100mm. The bending of fixed-end beams with concentrated load is analysed. Extreme values of the displacement for the beams material and RFSSW joints are emphasized. The effective stresses for the beams and RFSSW joints are calculated. Normal stresses in the top flanges, bottom flanges and webs are given.

Keywords: Aluminium - Cellular beams - Finite Element Method - Refill Friction Spot Stir Welding (RFSSW)

 

Finite element modelling of the residual stresses induced in thermally deposited coatings

Zimmerman, J.

Warsaw University of Technology, Faculty of Production Engineering, 85 Narbutta Str., 02-524 Warsaw, Poland

Archives of Metallurgy and Materials: Volume 59, Issue 2, 2014, Pages 593-599

Abstract: A numerical model based on the finite element method has been constructed with the aim to examine the residual stress state induced during thermal deposition of coatings on various substrates. The first stage of the modelling was designed to solve the problem of the high-velocity impact of a single spherical particle on a substrate using the "dynamics-explicit" module of the FEM ADINA software. In the second stage, the deposition process was simulated as a progressive growth of the coating until it achieved the desired thickness, and then the entire system was cooled to the ambient temperature. This problem was assumed to be thermo-mechanical and was also solved with the use of the FEM ADINA software. The samples assumed in the computations were cylindrical in shape and were built of a titanium coating, with three different thicknesses, deposited on an Al2O3 ceramic substrate by the detonation method. The numerical model was verified experimentally by measuring the deflection of the samples after their cooling. The computed values appeared to be in good agreement with those obtained experimentally.

Keywords: Coatings - Finite element modelling - Residual stress - Thermal spraying

 

An integrated ice-shedding model of electric transmission lines with consideration of ice adhesive/cohesive failure

McClure, G.1, Ji, K.2, Rui, X.2

1 Department of Civil Engineering and Applied Mechanics, Faculty of Engineering, McGill University, Montreal, Canada
2 Department of Power Machinery Engineering, School of Energy Power, Mechanical Engineering, North China Electric Power University, Beijing, 102206, China

Proceedings of the International Conference on Structural Dynamics , EURODYN, Volume 2014-January, 2014, Pages 3731-3736

Abstract: This research is an attempt to propose an integrated accreted ice failure model for iced overhead line conductors that will lead to more realistic nonlinear dynamic analysis of the ice-shedding phenomenon of transmission lines, by taking into account the adhesive/cohesive strength of ice deposits. Ice shedding induced by sudden mechanical forces is understood to be a two-stage process. First, the continuous ice deposits along the conductor span are broken into smaller separate ice chunks and fragments (ice fracture failure), and then these fragments detach from the cables and fall off due to insufficient cohesive strength within the ice or adhesive strength at the ice-cable interface (ice detachment failure). Two recent successive studies have developed computational models using ice deposit failure criteria based on the maximum effective plastic strain and the maximum bending stress. These models have yielded reasonably accurate results in predicting cable tensions and mid-span displacements, by comparing their numerical results with experimental data from tests carried out on a 4m reduced-scale model span with varying cable diameters and ice thickness, following sudden mechanical shock loads. However, there is still about 20% disparity in ice fracture rates between the computational results and experimental data, and it is deemed necessary to refine the ice failure model to introduce the effects of adhesive/cohesive forces. Therefore, as the first step towards the development of an integrated two-tier ice shedding criterion, the authors have improved the previous FE models, in terms of mesh size, load types and locations, material models and so on, to provide a better description of the experiment results. Then, the refined FE models of the reduced-scale span tests are used to check the newly proposed ice adhesive/cohesive failure criterion. The idea of this criterion is to simply compare the inertia forces acting on the fractured ice segments, and the ice adhesive strength or cohesive strength. The process is done automatically by a subroutine interacting with the nonlinear dynamic analysis commercial software ADINA. Although there is no satisfactory model to calculate the adhesive and cohesive strengths of glaze ice-especially for atmospheric ice, only several representative pairs of values are selected. Validation is underway to ascertain that the proposed two-tier glaze ice shedding criterion provides a more realistic description of the ice-shedding phenomenon of transmission lines than in the previous studies.

Keywords: Computational models - Ice failure - Nonlinear dynamics - Shock loads

 

Distribution of stress around the graphitic particles in cast iron microstructure

Vavro, J., Kováčiková, P.

University of Alexander Dubček in Trenčín, Slovakia

Applied Mechanics and Materials, Volume 486, 2014, Pages 20-25

Abstract: The given work is focused on the analysis of the distribution of stress around graphitic particles in microstructure of the ductile cast iron with the spheroidal shape of graphite (SGCI) and grey cast iron with the lamellar shape of graphite (LGCI). The analysis was made with help of finite element method in the software system ADINA.v.8.6.2. On the basis of the real structure, the finite element method was used for creation of the model which was subsequently used for calculation of the distribution of stress in the material structure. The input data for numerical analysis were obtained on the basis of evaluation of the structure by help of image analysis. The numerical analysis proved that the graphitic particles in the matrix cause the accumulation of the stress and the distribution of the given stress depends on the shape of the graphitic particles.

Keywords: Cast iron - Ductile cast iron - Finite element method - Grey cast iron - Microstructure - Numerical analysis - Stress

 

A new cladding embrittlement criterion derived from ring compression tests

Herb, J., Sievers, J., Sonnenburg, H.-G.

Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) MbH, Boltzmannstraße 14, 85748 Garching, Germany

Nuclear Engineering and Design, Volume 273, 1 July 2014, Pages 615-630

Abstract: It is of regulatory interest to prevent the breaking of fuel rods in LOCA transients. In current regulations this is accomplished by limiting the oxidation during LOCA to such an extent that still some residual ductility is preserved in the fuel rod cladding. The current oxidation limit in German as well as in US regulations is set to 17% ECR (Equivalent Cladding Reacted) which aims at maintaining a residual ductility for oxidized claddings. Recent ANL tests have shown that the combination of both oxidation and additionally hydrogen up-take affects the transition to zero-ductility. Furthermore, the oxidation during LOCA transient is accompanied by a significant up-take of hydrogen (secondary hydriding) if the fuel rod bursts during this transient. This secondary hydriding affects the cladding in the vicinity of the burst opening. These findings necessitate a new criterion for preserving cladding's strength. This paper describes a method how to derive a criterion which assures the required residual mechanical strength of the cladding for LOCA transients. This method utilizes the experimental results of 102 ring compression tests (RCT) conducted at ANL and KIT. RCTs of various cladding materials, oxidation levels and hydrogen content were considered. The basic approach was to compare the RCT test data with finite element analyses using the code ADINA. Starting with the cladding oxidation model of Leistikov, both the layer structure of the cladding and the distribution of the oxygen among these layers were determined. The mechanical properties of these layers were taken from MATPRO/FRAPCON models and adapted if necessary. For each RCT the calculated load/displacement curve followed the measured curve up to that displacement at which the first leaping drop appears which indicates the first crack in the test. For this displacement the maximum equivalent stress in the computational mesh is considered as burst stress. The burst stresses were determined for cladding materials Zircaloy-4, Zircaloy-4 HBR, ZIRLO and M5 at different levels of oxidation, hydrogen content and test temperatures. The ratio burst stress to yield stress (R) shows a linear dependency on the levels of oxidation and hydrogen up-take. The stress ratio R = 1 describes the transition from ductile to brittle behavior dependent on the levels of oxidation and the hydrogen up-take. This ratio can be applied for a conservative safety assessment of fuel rod claddings undergoing LOCA transients with fuel rod burst including secondary hydriding.

 

Anti-liquefaction characteristics of composite bucket foundations for offshore wind turbines

Zhang, P. 1,2,3, Xiong, K.3, Ding, H.1,2,3, Le, C.1,3

1 State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin, 300072, China
2 Key Laboratory of Coast Civil Structure Safety (Tianjin University), Ministry of Education, Tianjin, 300072, China
3 School of Civil Engineering, Tianjin University, Tianjin, 300072, China

Journal of Renewable and Sustainable Energy, Volume 6, Issue 5, 1 September 2014, Article number 053102

Abstract: Occurrence of liquefaction in saturated sandy deposits under structure foundation can cause a wide range of structural damages from minor settlement to general failure because of bearing capacity loss. By comparing traditional foundations for offshore wind turbines, the soil inside and underneath the composite bucket foundation is subjected to the overburden pressure from the foundation self-weight and constrained by a half-closed bucket skirt. The objective of this paper is to clarify the effects of the soil-foundation interaction on the soil liquefaction resistance around the skirt and under the foundation. The dynamic response of the composite bucket foundation during earthquake, including coupled soil mode of porous media, is calculated using the ADINA finite-element program. A typical configuration of composite bucket foundation is used for the analysis, and two earthquake waves (peak ground accelerations of 0.035 g and 0.22 g) are applied as the base acceleration. The results show that the composite bucket foundation exhibited good resistance to seismic action by improving the anti-liquefaction capacity of the soil inside and under the foundation because of the overburden pressure of the self-weight and the constraint effect of the skirt.

Keywords: Bucket foundation

 

Monte Carlo simulation for seismic analysis of a long span suspension bridge

Sgambi, L.1, Garavaglia, E.1, Basso, N.2, Bontempi, F.3

1 Department of Civil and Environmental Engineering, Politecnico di Milano, Milan, Italy
2 Department of Architecture, Tokyo Denki University, Tokyo, Japan
3 Department of Structural and Geotechnical Engineering, University of Rome La Sapienza, Rome, Italy

Engineering Structures,Volume 78, November 01, 2014, Pages 100-111

Abstract: The seismic analysis of long-span cable suspended bridges is undoubtedly a problem in structural analysis that involves a high number of uncertain parameters. In this work, through a probabilistic approach (Monte Carlo simulation) seismic analysis is carried out able to take into account the variability of certain factors relating to the seismic input. Displacement time histories, necessary to define seismic scenarios, are built artificially based on the response spectrum of the site. The analysis is carried out using a 3D numerical model built using one-dimensional finite elements using ADINA software code. This model has been developed in conjunction with a purpose-built program in FORTRAN language to conduct the Monte Carlo simulations. The results expressed in terms of displacements and stresses are described by their average value and their variance.

Keywords: Long span suspension bridge - Monte Carlo simulation - Seismic analysis - Uncertainties

 

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