资源类型

期刊论文 1519

会议视频 28

会议信息 2

年份

2024 1

2023 62

2022 115

2021 104

2020 76

2019 106

2018 86

2017 83

2016 65

2015 86

2014 83

2013 63

2012 80

2011 71

2010 75

2009 50

2008 73

2007 86

2006 35

2005 24

展开 ︾

关键词

风险分析 9

能源 7

分析 4

可持续发展 4

对策 4

影响因素 4

数值模拟 4

有限元 4

隧道 4

ANSYS 3

农业科学 3

抗击疫情 3

数值分析 3

环境 3

营养健康 3

裂缝 3

2035年 2

BNLAS 2

COVID-19 2

展开 ︾

检索范围:

排序: 展示方式:

FEM-based strain analysis study for multilayer sheet forming process

Rongjing ZHANG,Lihui LANG,Rizwan ZAFAR

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 373-379 doi: 10.1007/s11465-015-0371-9

摘要:

Fiber metal laminates have many advantages over traditional laminates (e.g., any type of fiber and resin material can be placed anywhere between the metallic layers without risk of failure of the composite fabric sheets). Furthermore, the process requirements to strictly control the temperature and punch force in fiber metal laminates are also less stringent than those in traditional laminates. To further explore the novel method, this study conducts a finite element method-based (FEM-based) strain analysis on multilayer blanks by using the 3A method. Different forming modes such as wrinkling and fracture are discussed by using experimental and numerical studies. Hydroforming is used for multilayer forming. The Barlat 2000 yield criteria and DYNAFORM/LS-DYNA are used for the simulations. Optimal process parameters are determined on the basis of fixed die-binder gap and variable cavity pressure. The results of this study will enhance the knowledge on the mechanics of multilayer structures formed by using the 3A method and expand its commercial applications.

关键词: finite element method (FEM)     strain analysis     multilayer sheet forming    

Adaptive selective ES-FEM limit analysis of cracked plane-strain structures

H. NGUYEN-XUAN,T. RABCZUK

《结构与土木工程前沿(英文)》 2015年 第9卷 第4期   页码 478-490 doi: 10.1007/s11709-015-0317-7

摘要: This paper presents a simple and efficient approach for predicting the plastic limit loads in cracked plane-strain structures. We use two levels of mesh repartitioning for the finite element limit analysis. The master level handles an adaptive primal-mesh process through a dissipation-based indicator. The slave level performs the subdivision of each triangle into three sub-triangles and constitutes a dual mesh from a pair of two adjacent sub-triangles shared by common edges of the primal mesh. Applying a strain smoothing projection to the strain rates on the dual mesh, the incompressibility constraint and the flow rule constraint are imposed over the edge-based smoothing domains and everywhere in the problem domain. The limit analysis problem is recast into the compact form of a second-order cone programming (SOCP) for the purpose of exploiting interior-point solvers. The present method retains a low number of optimization variables. It offers a convenient way for designing and solving the large-scale optimization problems effectively. Several benchmark examples are given to show the simplicity and effectiveness of the present method.

关键词: cracked structure     limit analysis     von Mises criterion     edge-based strain smoothing     second-order cone programming     adaptive    

用有限元强度折减法进行边坡稳定分析

郑颖人,赵尚毅,张鲁渝

《中国工程科学》 2002年 第4卷 第10期   页码 57-61

摘要:

通过对边坡非线性有限元模型进行强度折减,使边坡达到不稳定状态时,非线性有限元静力计算将不收敛,此时的折减系数就是稳定安全系数,同时可得到边坡破坏时的滑动面。传统条分法无法获得岩质边坡的滑动面与稳定安全系数。该方法开创了求岩质边坡滑动面与稳定安全系数的先例。文章对此法的计算精度以及影响因素进行了分析。算例表明采用摩尔-库仑等面积圆屈服准则求得的稳定安全系数与简化Bishop法的误差为3%~8%,与Spencer法的误差为1%~4%,证实了其实用于工程的可行性。

关键词: 边坡稳定分析     有限元强度折减法     屈服准则    

An extended cell-based smoothed discrete shear gap method (XCS-FEM-DSG3) for free vibration analysis

M. H. NGUYEN-THOI,L. Le-ANH,V. Ho-HUU,H. Dang-TRUNG,T. NGUYEN-THOI

《结构与土木工程前沿(英文)》 2015年 第9卷 第4期   页码 341-358 doi: 10.1007/s11709-015-0302-1

摘要: A cell-based smoothed discrete shear gap method (CS-FEM-DSG3) was recently proposed and proven to be robust for free vibration analyses of Reissner-Mindlin shell. The method improves significantly the accuracy of the solution due to softening effect of the cell-based strain smoothing technique. In addition, due to using only three-node triangular elements generated automatically, the CS-FEM-DSG3 can be applied flexibly for arbitrary complicated geometric domains. However so far, the CS-FEM-DSG3 has been only developed for analyzing intact structures without possessing internal cracks. The paper hence tries to extend the CS-FEM-DSG3 for free vibration analysis of cracked Reissner-Mindlin shells by integrating the original CS-FEM-DSG3 with discontinuous and crack−tip singular enrichment functions of the extended finite element method (XFEM) to give a so-called extended cell-based smoothed discrete shear gap method (XCS-FEM-DSG3). The accuracy and reliability of the novel XCS-FEM-DSG3 for free vibration analysis of cracked Reissner-Mindlin shells are investigated through solving three numerical examples and comparing with commercial software ANSYS.

关键词: cracked Reissner-Mindlin shell     free vibration analysis     cell-based smoothed discrete shear gap method (CS-FEM-DSG3)     extended cell-based smoothed discrete shear gap method (XCS-FEM-DSG3)     smoothed finite element methods (SFEM)    

Maximum entropy based finite element analysis of porous media

Emad NOROUZI, Hesam MOSLEMZADEH, Soheil MOHAMMADI

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 364-379 doi: 10.1007/s11709-018-0470-x

摘要: The maximum entropy theory has been used in a wide variety of physical, mathematical and engineering applications in the past few years. However, its application in numerical methods, especially in developing new shape functions, has attracted much interest in recent years. These shape functions possess the potential for performing better than the conventional basis functions in problems with randomly generated coarse meshes. In this paper, the maximum entropy theory is adopted to spatially discretize the deformation variable of the governing coupled equations of porous media. This is in line with the well-known fact that higher-order shape functions can provide more stable solutions in porous problems. Some of the benchmark problems in deformable porous media are solved with the developed approach and the results are compared with available references.

关键词: maximum entropy FEM     fully coupled multi-phase system     porous media    

Two-scale modeling of granular materials: A FEM-FEM approach

Yun-Zhu CAI, Yu-Ching WU

《结构与土木工程前沿(英文)》 2013年 第7卷 第3期   页码 304-315 doi: 10.1007/s11709-013-0213-y

摘要: In the present paper, a homogenization-based two-scale FEM-FEM model is developed to simulate compactions of visco-plastic granular assemblies. The granular structure consisting of two-dimensional grains is modeled by the microscopic finite element method at the small-scale level, and the homogenized viscous assembly is analyzed by the macroscopic finite element method at large-scale level. The link between scales is made using a computational homogenization method. The two-scale FEM-FEM model is developed in which each particle is treated individually with the appropriate constitutive relations obtained from a representative volume element, kinematic conditions, contact constraints, and elimination of overlap satisfied for every particle. The method could be used in a variety of problems that can be represented using granular media.

关键词: homogenization     two-scale     representative volume element     compaction     granular assembly     finite element method    

Three-dimensional seismic response analysis of a concrete-faced rockfill dam on overburden layers

Dakuo FENG, Ga ZHANG, Jianmin ZHANG,

《结构与土木工程前沿(英文)》 2010年 第4卷 第2期   页码 258-266 doi: 10.1007/s11709-010-0031-4

摘要: Reasonable seismic response analysis of a high rockfill dam is of great engineering significance in guiding its design and ensuring its seismic safety during operation, especially of a concrete-faced rockfill dam (CFRD) on overburden layers. The three-dimensional seismic behavior of the Miaojiaba CFRD is simulated and analyzed by the finite element method (FEM). The results indicate that: 1) the amplification coefficient along the dam axis gradually increases with the altitude, and reaches maximum at the dam crest; 2) the vertical residual deformation mainly exhibits downwards and reaches maximum near the dam crest; 3) the earthquake significantly aggravates the deformation of peripheral joints; 4) the impounding condition and overburden characteristics have great effects on the dam’s seismic response.

关键词: concrete-faced rockfill dam (CFRD)     overburden layer     dynamic analysis     finite element method (FEM)    

Seismic response reduction of a three-story building by an MR grease damper

Tomoki SAKURAI, Shin MORISHITA

《机械工程前沿(英文)》 2017年 第12卷 第2期   页码 224-233 doi: 10.1007/s11465-017-0413-6

摘要:

This paper describes an application of magneto-rheological (MR) grease dampers as seismic dampers for a three-story steel structure. MR fluid is widely known as a smart material with rheological properties that can be varied by magnetic field strength. This material has been applied to various types of devices, such as dampers, clutches, and engine mounts. However, the ferromagnetic particles dispersed in MR fluid settle out of the suspension after a certain interval because of the density difference between the particles and their carrier fluid. To overcome this defect, we developed a new type of controllable working fluid using grease as the carrier of magnetic particles. MR grease was introduced into a cylindrical damper, and the seismic performance of the damper was subsequently studied via numerical analysis. The analysis results of the MR grease damper were compared with those of other seismic dampers. We confirmed that the MR grease damper is an effective seismic damper.

关键词: MR grease damper     seismic damper     vibration control     structural response     FEM analysis    

Dynamic analysis of a rig shafting vibration based on finite element

Van Thanh NGO, Danmei XIE, Yangheng XIONG, Hengliang ZHANG, Yi YANG

《机械工程前沿(英文)》 2013年 第8卷 第3期   页码 244-251 doi: 10.1007/s11465-013-0264-8

摘要:

In recently, finite elements method (FEM) has been used most popular for analysis of stress, vibration, heat flow and many other phenomena. Taking a rig shafting as an example, this paper studies the lateral vibration of the rig shafting with multi-degree-of-freedom by using FEM. The FEM model is created and the eigenvalues and eigenvectors are calculated and analyzed to find natural frequencies, critical speeds, mode shapes and unbalance responses. Then critical and mode shapes are determined. Finally, responses of unbalance force are analyzed in case of undamped and damped system, and peaks of response are compared.

关键词: Finite element method (FEM)     lateral vibration     rig shafting     rotor-bearing system     dynamic characteristics    

Elastic analysis of heterogeneous thick-walled spherical pressure vessels with parabolic varying properties

Keyhan KARAMI, Majid ABEDI, Mohammad ZAMANI NEJAD, Mohammad Hassan LOTFIAN

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 433-438 doi: 10.1007/s11465-012-0336-1

摘要:

On the basis of plane elasticity theory (PET), the displacement and stress components in a thick-walled spherical pressure vessels made of heterogeneous materials subjected to internal and external pressure is developed. The mechanical properties except the Poisson’s ratio are assumed to obey the parabolic variations throughout the thickness. Effect of material inhomogeneity on the elastic deformations and stresses is investigated. The analytical solutions and the solutions carried out through the FEM have a good agreement. The values used in this study are arbitrary chosen to demonstrate the effect of inhomogeneity on displacements, and stresses distributions.

关键词: thick-walled spherical vessels     heterogeneous materials     FGM     FEM     parabolic varying properties    

Confined masonry as practical seismic construction alternative–the experience from the 2014 Cephalonia Earthquake

Fillitsa KARANTONI, Stavroula PANTAZOPOULOU, Athanasios GANAS

《结构与土木工程前沿(英文)》 2018年 第12卷 第3期   页码 270-290 doi: 10.1007/s11709-017-0390-1

摘要:

During August 1953 three strong earthquakes of magnitude ranging from 6.3 to 7.2 shook the Ionian Island of Cephalonia (Kefalonia), Greece, and destroyed almost the entire building stock of the Island which consisted primarily of traditional unreinforced masonry (URM) houses. The authorities went on to restructuring of the building stock, using a structural system that is most like what is known today as confined masonry. They designed about 14 types of one- to two-storey buildings providing the engineers with detailed construction plans. These buildings are known as “Arogi” buildings (Arogi in Greek meaning Aid). On the 24th of January and 3rd of February 2014, two earthquakes of magnitude 6.1 and 6.0 struck the island, causing significant soil damages, developing excessively high ground accelerations. Surprisingly, no damage was reported in the “Arogi” buildings. The seismic behavior of the buildings is examined by FEM linear analysis and it is compared to that of URM structures. Computed results illustrate that the displacements of identical URM buildings would be about twice the magnitudes observed in the corresponding “Arogi” ones, with the implication that the earthquake sequence of 2014 would have caused critical damage should the type of structure be of the URM type. Furthermore, it is illustrated that this low cost alternative method of construction is a very effective means of producing earthquake resilient structures, whereas further reduction of seismic displacement may be achieved in the order of 50% with commensurate effects on damage potential, when reinforced slabs are used to replace the timber roofs.

关键词: Cephalonia     confined masonry     comparative FEM analysis     unreinforced masonry     seismic damage    

3D finite element method (FEM) simulation of groundwater flow during backward erosion piping

Kristine VANDENBOER,Vera van BEEK,Adam BEZUIJEN

《结构与土木工程前沿(英文)》 2014年 第8卷 第2期   页码 160-166 doi: 10.1007/s11709-014-0257-7

摘要: Backward erosion piping is an important failure mechanism for cohesive water retaining structures which are founded on a sandy aquifer. At present, the prediction models for safety assessment are often based on 2D assumptions. In this work, a 3D numerical approach of the groundwater flow leading to the erosion mechanism of backward erosion piping is presented and discussed. Comparison of the 2D and 3D numerical results explicitly demonstrates the inherent 3D nature of the piping phenomenon. In addition, the influence of the seepage length is investigated and discussed for both piping initiation and piping progression. The results clearly indicate the superiority of the presented 3D numerical model compared to the established 2D approach. Moreover, the 3D numerical results enable a better understanding of the complex physical mechanism involved in backward erosion piping and thus can lead to a significant improvement in the safety assessment of water retaining structures.

关键词: backward erosion piping     groundwater flow     3D finite element method (FEM)    

Research on acoustic-structure sensitivity using FEM and BEM

ZHANG Jun, ZHAO Wenzhong, ZHANG Weiying

《机械工程前沿(英文)》 2007年 第2卷 第1期   页码 62-67 doi: 10.1007/s11465-007-0010-1

摘要: Acoustic-structure sensitivity is used to predict the change of acoustic pressure when a structure design variable is changed. The sensitivity is significant for reducing noise of structure. Using FEM (finite element method) and BEM (boundary element method) acoustic-structure sensitivity was formulated and presented. The dynamic response and response velocity sensitivity with respect to structure design variable were carried out by using structural FEM, the acoustic response and acoustic pressure sensitivity with respect to structure velocity were carried out by using acoustic BEM. Then, acoustic-structure sensitivity was computed by linking velocity sensitivity in FEM and acoustic sensitivity in BEM. This method was applied to an empty box as an example. Acoustic pressure sensitivity with respect to structure thickness achieved in frequency ranges 1 100 Hz, and its change rule along with stimulating frequency and design variable were analyzed. Results show that acoustic-structure sensitivity method linked with FEM and BEM is effective and correct.

关键词: sensitivity method     BEM     acoustic pressure     pressure sensitivity     frequency    

end-to-end 3d seismic simulation of underground structures due to point dislocation source by using an FK-FEM

Zhenning BA; Jisai FU; Zhihui ZHU; Hao ZHONG

《结构与土木工程前沿(英文)》 2022年 第16卷 第12期   页码 1515-1529 doi: 10.1007/s11709-022-0887-0

摘要: Based on the domain reduction idea and artificial boundary substructure method, this paper proposes an FK-FEM hybrid approach by integrating the advantages of FK and FEM (i.e., FK can efficiently generate high-frequency three translational motion, while FEM has rich elements types and constitutive models). An advantage of this approach is that it realizes the entire process simulation from point dislocation source to underground structure. Compared with the plane wave field input method, the FK-FEM hybrid approach can reflect the spatial variability of seismic motion and the influence of source and propagation path. This approach can provide an effective solution for seismic analysis of underground structures under scenario of earthquake in regions where strong earthquakes may occur but are not recorded, especially when active faults, crustal, and soil parameters are available. Taking Daikai subway station as an example, the seismic response of the underground structure is simulated after verifying the correctness of the approach and the effects of crustal velocity structure and source parameters on the seismic response of Daikai station are discussed. In this example, the influence of velocity structure on the maximum interlayer displacement angle of underground structure is 96.5% and the change of source parameters can lead to the change of structural failure direction.

关键词: source-to-structure simulation     FK-FEM hybrid approach     underground structures     point dislocation source    

Vibration-based crack prediction on a beam model using hybrid butterfly optimization algorithm with artificial neural network

Abdelwahhab KHATIR; Roberto CAPOZUCCA; Samir KHATIR; Erica MAGAGNINI

《结构与土木工程前沿(英文)》 2022年 第16卷 第8期   页码 976-989 doi: 10.1007/s11709-022-0840-2

摘要: Vibration-based damage detection methods have become widely used because of their advantages over traditional methods. This paper presents a new approach to identify the crack depth in steel beam structures based on vibration analysis using the Finite Element Method (FEM) and Artificial Neural Network (ANN) combined with Butterfly Optimization Algorithm (BOA). ANN is quite successful in such identification issues, but it has some limitations, such as reduction of error after system training is complete, which means the output does not provide optimal results. This paper improves ANN training after introducing BOA as a hybrid model (BOA-ANN). Natural frequencies are used as input parameters and crack depth as output. The data are collected from improved FEM using simulation tools (ABAQUS) based on different crack depths and locations as the first stage. Next, data are collected from experimental analysis of cracked beams based on different crack depths and locations to test the reliability of the presented technique. The proposed approach, compared to other methods, can predict crack depth with improved accuracy.

关键词: damage prediction     ANN     BOA     FEM     experimental modal analysis    

标题 作者 时间 类型 操作

FEM-based strain analysis study for multilayer sheet forming process

Rongjing ZHANG,Lihui LANG,Rizwan ZAFAR

期刊论文

Adaptive selective ES-FEM limit analysis of cracked plane-strain structures

H. NGUYEN-XUAN,T. RABCZUK

期刊论文

用有限元强度折减法进行边坡稳定分析

郑颖人,赵尚毅,张鲁渝

期刊论文

An extended cell-based smoothed discrete shear gap method (XCS-FEM-DSG3) for free vibration analysis

M. H. NGUYEN-THOI,L. Le-ANH,V. Ho-HUU,H. Dang-TRUNG,T. NGUYEN-THOI

期刊论文

Maximum entropy based finite element analysis of porous media

Emad NOROUZI, Hesam MOSLEMZADEH, Soheil MOHAMMADI

期刊论文

Two-scale modeling of granular materials: A FEM-FEM approach

Yun-Zhu CAI, Yu-Ching WU

期刊论文

Three-dimensional seismic response analysis of a concrete-faced rockfill dam on overburden layers

Dakuo FENG, Ga ZHANG, Jianmin ZHANG,

期刊论文

Seismic response reduction of a three-story building by an MR grease damper

Tomoki SAKURAI, Shin MORISHITA

期刊论文

Dynamic analysis of a rig shafting vibration based on finite element

Van Thanh NGO, Danmei XIE, Yangheng XIONG, Hengliang ZHANG, Yi YANG

期刊论文

Elastic analysis of heterogeneous thick-walled spherical pressure vessels with parabolic varying properties

Keyhan KARAMI, Majid ABEDI, Mohammad ZAMANI NEJAD, Mohammad Hassan LOTFIAN

期刊论文

Confined masonry as practical seismic construction alternative–the experience from the 2014 Cephalonia Earthquake

Fillitsa KARANTONI, Stavroula PANTAZOPOULOU, Athanasios GANAS

期刊论文

3D finite element method (FEM) simulation of groundwater flow during backward erosion piping

Kristine VANDENBOER,Vera van BEEK,Adam BEZUIJEN

期刊论文

Research on acoustic-structure sensitivity using FEM and BEM

ZHANG Jun, ZHAO Wenzhong, ZHANG Weiying

期刊论文

end-to-end 3d seismic simulation of underground structures due to point dislocation source by using an FK-FEM

Zhenning BA; Jisai FU; Zhihui ZHU; Hao ZHONG

期刊论文

Vibration-based crack prediction on a beam model using hybrid butterfly optimization algorithm with artificial neural network

Abdelwahhab KHATIR; Roberto CAPOZUCCA; Samir KHATIR; Erica MAGAGNINI

期刊论文