资源类型

期刊论文 259

年份

2023 12

2022 16

2021 18

2020 18

2019 28

2018 5

2017 7

2016 10

2015 13

2014 20

2013 10

2012 11

2011 11

2010 19

2009 12

2008 7

2007 11

2006 4

2005 8

2004 1

展开 ︾

关键词

有限元 7

有限元分析 5

有限元法 5

ANSYS 3

裂缝 3

三维有限元 2

可拓学 2

应力 2

有限元模型 2

混凝土 2

ACP1000 1

AFHW模型 1

ARMA模型 1

CFRP索斜拉桥 1

Cu(In 1

FHW 1

Ga)Se2 1

Halbach阵列 1

ISO标准火灾实验系统 1

展开 ︾

检索范围:

排序: 展示方式:

A “Sequential Design of Simulations” approach for exploiting and calibrating discrete element simulationsof cohesive powders

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 874-885 doi: 10.1007/s11705-021-2131-1

摘要: The flow behaviours of cohesive particles in the ring shear test were simulated and examined using discrete element method guided by a design of experiments methodology. A full factorial design was used as a screening design to reveal the effects of material properties of partcles. An augmented design extending the screening design to a response surface design was constructed to establish the relations between macroscopic shear stresses and particle properties. It is found that the powder flow in the shear cell can be classified into four regimes. Shear stress is found to be sensitive to particle friction coefficient, surface energy and Young’s modulus. A considerable fluctuation of shear stress is observed in high friction and low cohesion regime. In high cohesion regime, Young’s modulus appears to have a more significant effect on the shear stress at the point of incipient flow than the shear stress during the pre-shear process. The predictions from response surface designs were validated and compared with shear stresses measured from the Schulze ring shear test. It is found that simulations and experiments showed excellent agreement under a variety of consolidation conditions, which verifies the advantages and feasibility of using the proposed “Sequential Design of Simulations” approach.

关键词: discrete element method     cohesive materials     parameter calibration     ring shear cell     design of experiments    

Cohesive zone model-based analyses of localized leakage of segmentally lined tunnels

《结构与土木工程前沿(英文)》 2023年 第17卷 第4期   页码 503-521 doi: 10.1007/s11709-023-0927-4

摘要: This paper presents a novel approach for simulating the localized leakage behavior of segmentally lined tunnels based on a cohesive zone model. The proposed approach not only simulates localized leakage at the lining segment, but also captures the hydromechanically coupled seepage behavior at the segmental joints. It is first verified via a tunnel drainage experiment, which reveals its merits over the existing local hydraulic conductivity method. Subsequently, a parametric study is conducted to investigate the effects of the aperture size, stratum permeability, and spatial distribution of drainage holes on the leakage behavior, stratum seepage field, and leakage-induced mechanical response of the tunnel lining. The proposed approach yields more accurate results than the classical local hydraulic conductivity method. Moreover, it is both computationally efficient and stable. Localized leakage leads to reduced local ground pressure, which further induces outward deformation near the leakage point and slight inward deformation at its diametrically opposite side. A localized stress arch spanning across the leakage point is observed, which manifests as the rotation of the principal stresses in the adjacent area. The seepage field depends on both the number and location of the leakage zones. Pseudostatic seepage zones, in which the seepage rate is significantly lower than that of the adjacent area, appear when multiple seepage zones are considered. Finally, the importance of employing the hydromechanical coupled mechanism at the segment joints is highlighted by cases of shallowly buried tunnels subjected to surface loading and pressure tunnels while considering internal water pressure.

关键词: segmentally lined tunnel     localized leakage     cohesive element     hydraulic behavior     numerical modeling    

Simulation of cohesive crack growth by a variable-node XFEM

Weihua FANG, Jiangfei WU, Tiantang YU, Thanh-Tung NGUYEN, Tinh Quoc BUI

《结构与土木工程前沿(英文)》 2020年 第14卷 第1期   页码 215-228 doi: 10.1007/s11709-019-0595-6

摘要: A new computational approach that combines the extended finite element method associated with variable-node elements and cohesive zone model is developed. By using a new enriched technique based on sign function, the proposed model using 4-node quadrilateral elements can eliminate the blending element problem. It also allows modeling the equal stresses at both sides of the crack in the crack-tip as assumed in the cohesive model, and is able to simulate the arbitrary crack-tip location. The multiscale mesh technique associated with variable-node elements and the arc-length method further improve the efficiency of the developed approach. The performance and accuracy of the present approach are illustrated through numerical experiments considering both mode-I and mixed-mode fracture in concrete.

关键词: extended finite element method     cohesive zone model     sign function     crack propagation    

Hydraulic fracturing pressure of concentric double-layered cylinder in cohesive soil

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 937-947 doi: 10.1007/s11709-021-0754-4

摘要: This study aims to investigate hydrofracturing in double-layered soil through theoretical and experimental analysis, as multilayered soils where the difference in mechanical properties exists are generally encountered in practical engineering. First, an analytical solution for fracturing pressure in two different concentric regions of soil was presented based on the cavity expansion theory. Then, several triaxial hydraulic fracturing tests were carried out to validate the analytical solution. The comparison between the experimental and analytical results indicates the remarkable accuracy of the derived formula, and the following conclusions were also obtained. First, there is a linear relationship between the fracturing pressure and confining pressure in concentric double-layered cohesive soil. Second, when the internal-layer soil is softer than the external-layer soil, the presence of internal soil on the fracturing pressure approximately brings the weakening effect, and the greater strength distinction between the two layers, the greater the weakening effect. Third, when the internal-layer soil is harder than the external-layer soil, the existence of the internal-layer soil has a strengthening effect on the fracturing pressure regardless of the proportion of internal-layer soil. Moreover, the influence of strength distinction between the two layers on the fracturing pressure is significant when the proportion of internal-layer soil is less than half, while it’s limited when the proportion is more than half. The proposed solution is potentially useful for geotechnical problems involving aspects of cohesive soil layering in a composite formation.

关键词: hydraulic fracturing pressure     layered     cavity expansion theory     triaxial fracturing test     cohesive soil    

Isogeometric cohesive zone model for thin shell delamination analysis based on Kirchhoff-Love shell model

Tran Quoc THAI, Timon RABCZUK, Xiaoying ZHUANG

《结构与土木工程前沿(英文)》 2020年 第14卷 第2期   页码 267-279 doi: 10.1007/s11709-019-0567-x

摘要: We present a cohesive zone model for delamination in thin shells and composite structures. The isogeometric (IGA) thin shell model is based on Kirchhoff-Love theory. Non-Uniform Rational B-Splines (NURBS) are used to discretize the exact mid-surface of the shell geometry exploiting their C -continuity property which avoids rotational degrees of freedom. The fracture process zone is modeled by interface elements with a cohesive law. Two numerical examples are presented to test and validate the proposed formulation in predicting the delamination behavior of composite structures.

关键词: cohesive zone model     IGA     Kirchhoff-Love model     thin shell analysis     delamination    

Effect of interface adhesion factor on the bearing capacity of strip footing placed on cohesive soil

《结构与土木工程前沿(英文)》 2021年 第15卷 第6期   页码 1494-1503 doi: 10.1007/s11709-021-0768-y

摘要: The problem related to bearing capacity of footing either on pure soil or on pure rock mass has been investigated over the years. Currently, no study deals with the bearing capacity of strip footing on a cohesive soil layer overlying rock mass. Therefore, by implementing the lower bound finite element limit analysis in conjunction with the second-order cone programming and the power cone programming, the ultimate bearing capacity of a strip footing located on a cohesive soil overlying rock mass is determined in this study. By considering the different values of interface adhesion factor (αcr) between the cohesive soil and rock mass, the ultimate bearing capacity of strip footing is expressed in terms of influence factor (If) for different values of cohesive soil layer cover ratio (Tcs/B). The failure of cohesive soil is modeled by using Mohr−Coulomb yield criterion, whereas Generalized Hoek−Brown yield criterion is utilized to model the rock mass at failure. The variations ofIf with different magnitudes of αcr are studied by considering the influence of the rock mass strength parameters of beneath rock mass layer. To examine stress distribution at different depths, failure patterns are also plotted.

关键词: bearing capacity     soil-rock interface     Hoek−Brown yield criterion     plasticity     limit analysis    

influence of delamination on the stiffness of composite pipes under compressive transverse loading using cohesive

Sattar MALEKI, Roham RAFIEE, Abolfazl HASANNIA, Mohammad Reza HABIBAGAHI

《结构与土木工程前沿(英文)》 2019年 第13卷 第6期   页码 1316-1323 doi: 10.1007/s11709-019-0555-1

摘要: The effect of delamination on the stiffness reduction of composite pipes is studied in this research. The stiffness test of filament wound composite pipes is simulated using cohesive zone method. The modeling is accomplished to study the effect of the geometrical parameters including delamination size and its position with respect to loading direction on stiffness of the composite pipes. At first, finite element results for stiffness test of a perfect pipe without delamination are validated with the experimental results according to ASTM D2412. It is seen that the finite element results agree well with experimental results. Then the finite element model is developed for composite pips with delaminated areas with different primary shapes. Thus, the effect of the size of delaminated region on longitudinal and tangential directions and also its orientation with respect to loading direction on delamination propagation and stiffness reduction of the pipes is assessed.

关键词: delamination     composite pipes     stiffness test     cohesive zone method    

The effects of mismatch fracture properties in encapsulation-based self-healing concrete using cohesive-zone

Luthfi Muhammad MAULUDIN, Chahmi OUCIF, Timon RABCZUK

《结构与土木工程前沿(英文)》 2020年 第14卷 第3期   页码 792-801 doi: 10.1007/s11709-020-0629-0

摘要: Finite element analysis is developed to simulate the breakage of capsule in capsule-based self-healing concrete. A 2D circular capsule with different core-shell thickness ratios embedded in the mortar matrix is analyzed numerically along with their interfacial transition zone. Zero-thickness cohesive elements are pre-inserted into solid elements to represent potential cracks. This study focuses on the effects of mismatch fracture properties, namely fracture strength and energy, between capsule and mortar matrix into the breakage likelihood of the capsule. The extensive simulations of 2D specimens under uniaxial tension were carried out to investigate the key features on the fracture patterns of the capsule and produce the fracture maps as the results. The developed fracture maps of capsules present a simple but valuable tool to assist the experimentalists in designing appropriate capsule materials for self-healing concrete.

关键词: self-healing concrete     interfacial zone     capsule materials     cohesive elements     fracture maps    

Application of a weakly compressible smoothed particle hydrodynamics multi-phase model to non-cohesive

Rasoul MEMARZADEH, Gholamabbas BARANI, Mahnaz GHAEINI-HESSAROEYEH

《结构与土木工程前沿(英文)》 2018年 第12卷 第3期   页码 412-424 doi: 10.1007/s11709-017-0432-8

摘要:

The subject of present study is the application of mesh free Lagrangian two-dimensional non-cohesive sediment transport model applied to a two-phase flow over an initially trapezoidal-shaped sediment embankment. The governing equations of the present model are the Navier-Stocks equations solved using Weakly Compressible Smoothed Particle Hydrodynamics (WCSPH) method. To simulate the movement of sediment particles, the model considers a powerful two-part technique; when the sediment phase has rigid behavior, only the force term due to shear stress in the Navier-Stokes equations is used for simulation of sediment particles’ movement. Otherwise, all the Navier-Stokes force terms are used for transport simulation of sediment particles. In the present model, the interactions between different phases are calculated automatically, even with considerable difference between the density and viscosity of phases. Validation of the model is performed using simulation of available laboratory experiments, and the comparison between computational results and experimental data shows that the model generally predicts well the flow propagation over movable beds, the induced sediment transport and bed changes, and temporal evolution of embankment breaching.

关键词: WCSPH method     non-cohesive sediment transport     rheological model     two-part technique     two-phase dam break    

Influence of axial load on the lateral pile groups response in cohesionless and cohesive soil

Jasim M. ABBASA,Zamri CHIK,Mohd Raihan TAHA

《结构与土木工程前沿(英文)》 2015年 第9卷 第2期   页码 176-193 doi: 10.1007/s11709-015-0289-7

摘要: The lateral response of single and group of piles under simultaneous vertical and lateral loads has been analyzed using a 3D finite element approach. The response in this assessment considered lateral pile displacement and lateral soil resistance and corresponding - curve. As a result, modified - curves for lateral single pile response were improved with respect to the influence of increasing axial load intensities. The improved plots can be used for lateral loaded pile design and to produce the group action design -multiplier curves and equations. The effect of load combination on the lateral pile group response was performed on three pile group configurations (i.e., 2×1, 2×2 and 3×2) with four pile spacings (i.e., = 2 , 4 , 6 and 8 ). As a result, design curves were developed and applied on the actual case studies and similar expected cases for assessment of pile group behavior using improved p-multiplier. A design equation was derived from predicted design curves to be used in the evaluation of the lateral pile group action taking into account the effect of axial load intensities. It was found that the group interaction effect led to reduced lateral resistance for the pile in the group relative to that for the single pile in case of pure lateral load. While, in case of simultaneous combined loads, large axial load intensities (i.e., more than 6 , where is lateral load values) will have an increase in -multiplier by approximately 100% and will consequently contribute to greater group piles capacities.

关键词: piles     pile group     spacing     configuration     combined load    

混凝土裂缝端部粘聚力的计算

徐世烺,王利民

《中国工程科学》 2002年 第4卷 第5期   页码 53-58

摘要:

混凝土裂缝端部断裂过程区的粘聚力分布是导致混凝土断裂呈现非线性特性的重要原因。基于混凝土的断裂特性和虚拟裂缝端部存在粘聚力的分析模型,并通过分布函数的特性分析,提出了粘聚力分布函数的两种简化表达式:一为单参数待定式,另一为双参数待定式。由变形体叠加原理,推导出计算单参数待定函数公式和计算双参数待定函数代数方程组。进而通过裂缝张开位移实测数据即可求得粘聚力分布,并且给出了适当的算例分析和讨论。

关键词: 混凝土     裂缝张开位移     虚拟裂缝粘聚力     代数方程    

New pseudo-dynamic analysis of two-layered cohesive-friction soil slope and its numerical validation

Suman HAZARI, Sima GHOSH, Richi Prasad SHARMA

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1492-1508 doi: 10.1007/s11709-020-0679-3

摘要: Natural slopes consist of non-homogeneous soil profiles with distinct characteristics from slopes made of homogeneous soil. In this study, the limit equilibrium modified pseudo-dynamic method is used to analyze the stability of two-layered soil slopes in which the failure surface is assumed to be a logarithmic spiral. The zero-stress boundary condition at the ground surface under the seismic loading condition is satisfied. New formulations derived from an analytical method are proposed for the predicting the seismic response in two-layered soil. A detailed parametric study was performed in which various parameters (seismic accelerations, damping, cohesion, and angle of internal friction) were varied. The results of the present method were compared with those in the available literature. The present analytical analysis was also verified against the finite element analysis results.

关键词: layered soil     limit equilibrium method     seismic analysis     damping     PLAXIS    

黏聚裂纹阻抗的弯曲梁承载力

王利民,徐世,任传波

《中国工程科学》 2007年 第9卷 第2期   页码 30-35

摘要:

在混凝土类软化材料断裂研究中,裂纹端部损伤区被简化为具有黏聚应力分布的非线性裂纹,该黏 聚力对裂纹扩展有阻抗作用。裂纹体的应力强度因子是断裂力学标志载荷作用与几何构型因素的量化表达指标; 黏聚力形成的阻抗强度因子数值,与黏聚裂纹长度和材料极值拉伸应力存在数量关系。通过双K断裂判据,以 带切口的三点弯曲梁为断裂力学模型,分析了裂纹黏聚阻力对断裂过程的影响规律,计算该弯曲梁结构断裂试 样的最大承担载荷;其结果比较符合实验数据。

关键词: 黏聚裂纹     三点弯曲梁     混凝土     双K断裂参数     结构承载力    

Studies of fiber-matrix debonding

Navneet DRONAMRAJU,Johannes SOLASS,Jörg HILDEBRAND

《结构与土木工程前沿(英文)》 2015年 第9卷 第4期   页码 448-456 doi: 10.1007/s11709-015-0316-8

摘要: In this paper, the debonding of a single fiber-matrix system of carbon fiber reinforced composite (CFRP) AS4/Epson 828 material is studied using Cohesive Zone Model (CZM). The effect of parameters namely, maximum tangential contact stress, tangential slip distance and artificial damping coefficient on the debonding length at the interface of the fiber-matrix is analyzed. Contact elements used in the CZM are coupled based on a bilinear stress-strain curve. Load is applied on the matrix, tangential to the interface. Hence, debonding is observed primarily in Mode II. Wide range of values are considered to study the inter-dependency of the parameters and its effect on debonding length. Out of the three parameters mentioned, artificial damping coefficient and tangential slip distance significantly affect debonding length. A thorough investigation is recommended for case wise interface debonding analysis, to estimate the optimal parametric values while using CZM.

关键词: single fibre     cohesive zone model     interface debonding     carbon fiber reinforced composite (CFRP)    

Computational modeling of fracture in capsule-based self-healing concrete: A 3D study

《结构与土木工程前沿(英文)》 2021年 第15卷 第6期   页码 1337-1346 doi: 10.1007/s11709-021-0781-1

摘要: We present a three-dimensional (3D) numerical model to investigate complex fracture behavior using cohesive elements. An efficient packing algorithm is employed to create the mesoscale model of heterogeneous capsule-based self-healing concrete. Spherical aggregates are used and directly generated from specified size distributions with different volume fractions. Spherical capsules are also used and created based on a particular diameter, and wall thickness. Bilinear traction-separation laws of cohesive elements along the boundaries of the mortar matrix, aggregates, capsules, and their interfaces are pre-inserted to simulate crack initiation and propagation. These pre-inserted cohesive elements are also applied into the initial meshes of solid elements to account for fracture in the mortar matrix. Different realizations are carried out and statistically analyzed. The proposed model provides an effective tool for predicting the complex fracture response of capsule-based self-healing concrete at the meso-scale.

关键词: 3D fracture     self-healing concrete     spherical     cohesive elements     heterogeneous    

标题 作者 时间 类型 操作

A “Sequential Design of Simulations” approach for exploiting and calibrating discrete element simulationsof cohesive powders

期刊论文

Cohesive zone model-based analyses of localized leakage of segmentally lined tunnels

期刊论文

Simulation of cohesive crack growth by a variable-node XFEM

Weihua FANG, Jiangfei WU, Tiantang YU, Thanh-Tung NGUYEN, Tinh Quoc BUI

期刊论文

Hydraulic fracturing pressure of concentric double-layered cylinder in cohesive soil

期刊论文

Isogeometric cohesive zone model for thin shell delamination analysis based on Kirchhoff-Love shell model

Tran Quoc THAI, Timon RABCZUK, Xiaoying ZHUANG

期刊论文

Effect of interface adhesion factor on the bearing capacity of strip footing placed on cohesive soil

期刊论文

influence of delamination on the stiffness of composite pipes under compressive transverse loading using cohesive

Sattar MALEKI, Roham RAFIEE, Abolfazl HASANNIA, Mohammad Reza HABIBAGAHI

期刊论文

The effects of mismatch fracture properties in encapsulation-based self-healing concrete using cohesive-zone

Luthfi Muhammad MAULUDIN, Chahmi OUCIF, Timon RABCZUK

期刊论文

Application of a weakly compressible smoothed particle hydrodynamics multi-phase model to non-cohesive

Rasoul MEMARZADEH, Gholamabbas BARANI, Mahnaz GHAEINI-HESSAROEYEH

期刊论文

Influence of axial load on the lateral pile groups response in cohesionless and cohesive soil

Jasim M. ABBASA,Zamri CHIK,Mohd Raihan TAHA

期刊论文

混凝土裂缝端部粘聚力的计算

徐世烺,王利民

期刊论文

New pseudo-dynamic analysis of two-layered cohesive-friction soil slope and its numerical validation

Suman HAZARI, Sima GHOSH, Richi Prasad SHARMA

期刊论文

黏聚裂纹阻抗的弯曲梁承载力

王利民,徐世,任传波

期刊论文

Studies of fiber-matrix debonding

Navneet DRONAMRAJU,Johannes SOLASS,Jörg HILDEBRAND

期刊论文

Computational modeling of fracture in capsule-based self-healing concrete: A 3D study

期刊论文