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An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1531-1544 doi: 10.1007/s11709-020-0675-7

摘要: Some of the current concrete damage plasticity models in the literature employ a single damage variable for both the tension and compression regimes, while a few more advanced models employ two damage variables. Models with a single variable have an inherent difficulty in accounting for the damage accrued due to tensile and compressive actions in appropriately different manners, and their mutual dependencies. In the current models that adopt two damage variables, the independence of these damage variables during cyclic loading results in the failure to capture the effects of tensile damage on the compressive behavior of concrete and vice-versa. This study presents a cyclic model established by extending an existing monotonic constitutive model. The model describes the cyclic behavior of concrete under multiaxial loading conditions and considers the influence of tensile/compressive damage on the compressive/tensile response. The proposed model, dubbed the enhanced concrete damage plasticity model (ECDPM), is an extension of an existing model that combines the theories of classical plasticity and continuum damage mechanics. Unlike most prior studies on models in the same category, the performance of the proposed ECDPM is evaluated using experimental data on concrete specimens at the material level obtained under cyclic multiaxial loading conditions including uniaxial tension and confined compression. The performance of the model is observed to be satisfactory. Furthermore, the superiority of ECDPM over three previously proposed constitutive models is demonstrated through comparisons with the results of a uniaxial tension-compression test and a virtual test.

关键词: damage plasticity model     plain concrete     cyclic loading     multiaxial loading conditions    

Endochronic damage constitutive model for fully-graded aggregate mass concrete

SONG Yupu, WANG Huailiang

《结构与土木工程前沿(英文)》 2007年 第1卷 第3期   页码 274-280 doi: 10.1007/s11709-007-0035-x

摘要: The behavior of deformation and strength of a fully-graded aggregate concrete under complex stress state is the basis of the nonlinear analysis and design for mass concrete structures such as concrete dams. In this paper, based on the combined endochronic theory with damage mechanics and on the quantities of experimental data, an endochronic damage constitutive model suitable for various aggregate grade concrete is proposed. This model takes into consideration the scale effect and the effect of wet screen sieve of aggregate in which the concept of yield surface is not needed and the difference of damage evolution rule of various graded aggregate concrete is a concern. The proposed model is used to analyze the deformation and strength of fully-graded aggregate mass concrete and the wet screened aggregate concrete specimens. The calculated results are in good agreement with experimental data, which can be used as a guide for the design of arch dams and other mass concrete structures.

关键词: concept     surface     design     concern     strength    

Nonlinear cumulative damage model for multiaxial fatigue

SHANG De-guang, SUN Guo-qin, DENG Jing, YAN Chu-liang

《机械工程前沿(英文)》 2006年 第1卷 第3期   页码 265-269 doi: 10.1007/s11465-006-0035-x

摘要: On the basis of the continuum fatigue damage theory, a nonlinear uniaxial fatigue cumulative damage model is first proposed. In order to describe multiaxial fatigue damage characteristics, a nonlinear multiaxial fatigue cumulative damage model is developed based on the critical plane approach. The proposed model can consider the multiaxial fatigue limit, mean hydrostatic pressure and the unseparated characteristic for the damage variables and loading parameters. The recurrence formula of fatigue damage model was derived under multilevel loading, which is used to predict multiaxial fatigue life. The results showed that the proposed nonlinear multiaxial fatigue cumulative damage model is better than Miner s rule.

Damage-constitutive model for seawater coral concrete using different stirrup confinements subjected

《结构与土木工程前沿(英文)》 2023年 第17卷 第3期   页码 429-447 doi: 10.1007/s11709-022-0913-2

摘要: Recently, the application of detrital coral as an alternative to natural aggregates in marine structures has attracted increased attention. In this study, research on the compressive performance of coral aggregate concrete (CAC) confined using steel stirrups with anti-rust treatment was experimentally conducted. A total of 45 specimens were cast, including 9 specimens without stirrups and under different strength grades (C20, C30, and C40) and 36 specimens under different strength grades (C20, C30, and C40). Moreover, three stirrup levels (rectangular, diamond-shaped compound, and spiral stirrups) and different stirrup spacings (40, 50, 60, and 70 mm) were used. Subsequently, the stress−strain curves of specimens subjected to axial loading were measured. The effects of the stirrup spacing and stirrup configurations on the stress and strain were investigated, respectively, and the lateral effective stress of the different stirrups was calculated based on the cohesive-elastic ring model and modified elastic beam theory. Moreover, a damage-constitutive model of CAC considering the lateral stress was set up based on damage mechanics theory. The results indicated an increase in the stress and strain with a decrease in the stirrup spacing, and the adopted stirrup ratio had a better strengthening effect than the different concrete grades, and the variation in the deformation was restricted by the performance of coral coarse aggregate (CA). However, an increment in the lateral strain was observed with an increase in the axial strain. The lateral stress model showed a good agreement with the experimental data, and the proposed damage-constitutive model had a good correlation with the measured stress−strain curves.

关键词: coral aggregate concrete     stress−strain curves     lateral effective stress     peak stress     axial−lateral curves     damage-constitutive model.    

An efficient two-stage approach for structural damage detection using meta-heuristic algorithms and groupmethod of data handling surrogate model

Hamed FATHNEJAT, Behrouz AHMADI-NEDUSHAN

《结构与土木工程前沿(英文)》 2020年 第14卷 第4期   页码 907-929 doi: 10.1007/s11709-020-0628-1

摘要: In this study, the performance of an efficient two-stage methodology which is applied in a damage detection system using a surrogate model of the structure has been investigated. In the first stage, in order to locate the damage accurately, the performance of the modal strain energy based index for using different numbers of natural mode shapes has been evaluated using the confusion matrix. In the second stage, to estimate the damage extent, the sensitivity of most used modal properties due to damage, such as natural frequency and flexibility matrix is compared with the mean normalized modal strain energy (MNMSE) of suspected damaged elements. Moreover, a modal property change vector is evaluated using the group method of data handling (GMDH) network as a surrogate model during damage extent estimation by optimization algorithm; in this part of methodology, the performance of the three popular optimization algorithms including particle swarm optimization (PSO), bat algorithm (BA), and colliding bodies optimization (CBO) is examined and in this regard, root mean square deviation ( ) based on the modal property change vector has been proposed as an objective function. Furthermore, the effect of noise in the measurement of structural responses by the sensors has also been studied. Finally, in order to achieve the most generalized neural network as a surrogate model, GMDH performance is compared with a properly trained cascade feed-forward neural network (CFNN) with log-sigmoid hidden layer transfer function. The results indicate that the accuracy of damage extent estimation is acceptable in the case of integration of PSO and MNMSE. Moreover, the GMDH model is also more efficient and mimics the behavior of the structure slightly better than CFNN model.

关键词: two-stage method     modal strain energy     surrogate model     GMDH     optimization damage detection    

Damage mechanism and evaluation model of compressor impeller remanufacturing blanks: A review

Haiyang LU, Yanle LI, Fangyi LI, Xingyi ZHANG, Chuanwei ZHANG, Jiyu DU, Zhen LI, Xueju RAN, Jianfeng LI, Weiqiang WANG

《机械工程前沿(英文)》 2019年 第14卷 第4期   页码 402-411 doi: 10.1007/s11465-019-0548-8

摘要: The theoretical and technological achievements in the damage mechanism and evaluation model obtained through the national basic research program “Key Fundamental Scientific Problems on Mechanical Equipment Remanufacturing” are reviewed in this work. Large centrifugal compressor impeller blanks were used as the study object. The materials of the blanks were FV520B and KMN. The mechanism and evaluation model of ultra-high cycle fatigue, erosion wear, and corrosion damage were studied via theoretical calculation, finite element simulation, and experimentation. For ultra-high cycle fatigue damage, the characteristics of ultra-high cycle fatigue of the impeller material were clarified, and prediction models of ultra-high cycle fatigue strength were established. A residual life evaluation technique based on the “ - - ” (where was the nonlinear parameter, was the Vickers hardness, and was the fatigue life) double criterion method was proposed. For erosion wear, the flow field of gas-solid two-phase flow inside the impeller was simulated, and the erosion wear law was clarified. Two models for erosion rate and erosion depth calculation were established. For corrosion damage, the electrochemical and stress corrosion behaviors of the impeller material and welded joints in H S/CO environment were investigated. (critical stress intensity factor) and d /d (crack growth rate, where is the total crack length and is time) varied with H S concentration and temperature, and their variation laws were revealed. Through this research, the key scientific problems of the damage behavior and mechanism of remanufacturing objects in the multi-strength field and cross-scale were solved. The findings provide theoretical and evaluation model support for the analysis and evaluation of large centrifugal compressor impellers before remanufacturing.

关键词: remanufacturing     centrifugal compressor impeller     remanufacturing blank     damage mechanism     evaluation model    

Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

João Pedro SANTOS,Christian CREMONA,André D. ORCESI,Paulo SILVEIRA,Luis CALADO

《结构与土木工程前沿(英文)》 2015年 第9卷 第1期   页码 1-16 doi: 10.1007/s11709-014-0277-3

摘要: A large amount of researches and studies have been recently performed by applying statistical and machine learning techniques for vibration-based damage detection. However, the global character inherent to the limited number of modal properties issued from operational modal analysis may be not appropriate for early-damage, which has generally a local character. The present paper aims at detecting this type of damage by using static SHM data and by assuming that early-damage produces dead load redistribution. To achieve this objective a data driven strategy is proposed, consisting of the combination of advanced statistical and machine learning methods such as principal component analysis, symbolic data analysis and cluster analysis. From this analysis it was observed that, under the noise levels measured on site, the proposed strategy is able to automatically detect stiffness reduction in stay cables reaching at least 1%.

关键词: structural health monitoring     early-damage detection     principal component analysis     symbolic data     symbolic dissimilarity measures     cluster analysis     numerical model     damage simulations    

Regional seismic-damage prediction of buildings under mainshock–aftershock sequence

Xinzheng LU, Qingle CHENG, Zhen XU, Chen XIONG

《工程管理前沿(英文)》 2021年 第8卷 第1期   页码 122-134 doi: 10.1007/s42524-019-0072-x

摘要: Strong aftershocks generally occur following a significant earthquake. Aftershocks further damage buildings weakened by mainshocks. Thus, the accurate and efficient prediction of aftershock-induced damage to buildings on a regional scale is crucial for decision making for post-earthquake rescue and emergency response. A framework to predict regional seismic damage of buildings under a mainshock–aftershock (MS–AS) sequence is proposed in this study based on city-scale nonlinear time-history analysis (THA). Specifically, an MS–AS sequence-generation method is proposed to generate a potential MS–AS sequence that can account for the amplification, spectrum, duration, magnitude, and site condition of a target area. Moreover, city-scale nonlinear THA is adopted to predict building seismic damage subjected to MS–AS sequences. The accuracy and reliability of city-scale nonlinear THA for an MS–AS sequence are validated by as-recorded seismic responses of buildings and simulation results in published literature. The town of Longtoushan, which was damaged during the Ludian earthquake, is used as a case study to illustrate the detailed procedure and advantages of the proposed framework. The primary conclusions are as follows. (1) Regional seismic damage of buildings under an MS–AS sequence can be predicted reasonably and accurately by city-scale nonlinear THA. (2) An MS–AS sequence can be generated reasonably by the proposed MS–AS sequence-generation method. (3) Regional seismic damage of buildings under different MS–AS scenarios can be provided efficiently by the proposed framework, which in turn can provide a useful reference for earthquake emergency response and scientific decision making for earthquake disaster relief.

关键词: regional seismic damage prediction     city-scale nonlinear time-history analysis     mainshock–aftershock sequence     multiple degree-of-freedom (MDOF) model     2014 Ludian earthquake    

Intermediate HSS bracing members during seismic excitations: modeling, design, and behavior

Madhar HADDAD

《结构与土木工程前沿(英文)》 2018年 第12卷 第1期   页码 148-162 doi: 10.1007/s11709-016-0375-5

摘要: Concentric hollow structural section (HSS) bracing members are used frequently in steel framed structural systems to resist seismic excitations. Finite element modeling of the HSS braces that utilizes the true stress-strain curves produces hysteresis responses that are reasonable matches to the experimental response. True stress-strain curves are obtained from coupon tests or stub-column tests while utilizing an exponential function or strain hardening rule with a trial and error procedure to obtain the hysteresis behavior. In the current study, the true stress-strain curves are directly obtained from tests on stub-columns extracted from the full scale HSS bracing members away from the mid-length plastic hinge after cyclic testing. Two experimental tests (Shaback 2001 and Haddad 2004) were used to validate the model. Results indicate that the stress-strain curves for these braces are not unique. A refined damage accumulation model for ultra-low-cycle fatigue is implemented to predict fracture of the brace tests. The refined damage model is then used in the finite element modeling to predict fracture of braces in a chevron braced frame of an eight-storey building subjected to selected ground motions analyzed using OpenSees program. Results indicate that all braces could sustain the selected earthquake records without fracture.

关键词: HSS     FEM     stress-strain curves     damage model    

Uncertainty quantification of stability and damage detection parameters of coupled hydrodynamic-ground

Nazim Abdul NARIMAN, Tom LAHMER, Peyman KARAMPOUR

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 303-323 doi: 10.1007/s11709-018-0462-x

摘要: In this paper, models of the global system of the Koyna dam have been created using ABAQUS software considering the dam-reservoir-foundation interaction. Non coupled models and the coupled models were compared regarding the horizontal displacement of the dam crest and the differential settlement of the dam base in clay foundation. Meta models were constructed and uncertainty quantification process was adopted by the support of Sobol’s sensitivity indices considering five uncertain parameters by exploiting Box-Behnken experimental method. The non coupled models results determined overestimated predicted stability and damage detection in the dam. The rational effects of the reservoir height were very sensitive in the variation of the horizontal displacement of the dam crest with a small interaction effect with the beta viscous damping coefficient of the clay foundation. The modulus of elasticity of the clay foundation was the decisive parameter regarding the variation of the differential settlement of the dam base. The XFEM approach has been used for damage detection in relation with both minimum and maximum values of each uncertain parameter. Finally the effects of clay and rock foundations were determined regarding the resistance against the propagation of cracks in the dam, where the rock foundation was the best.

关键词: massed foundation     hydrodynamic pressure     Box-Behnken method     meta model     Sobol’s sensitivity indices    

Optimal CNN-based semantic segmentation model of cutting slope images

Mansheng LIN; Shuai TENG; Gongfa CHEN; Jianbing LV; Zhongyu HAO

《结构与土木工程前沿(英文)》 2022年 第16卷 第4期   页码 414-433 doi: 10.1007/s11709-021-0797-6

摘要: This paper utilizes three popular semantic segmentation networks, specifically DeepLab v3+, fully convolutional network (FCN), and U-Net to qualitively analyze and identify the key components of cutting slope images in complex scenes and achieve rapid image-based slope detection. The elements of cutting slope images are divided into 7 categories. In order to determine the best algorithm for pixel level classification of cutting slope images, the networks are compared from three aspects: a) different neural networks, b) different feature extractors, and c) 2 different optimization algorithms. It is found that DeepLab v3+ with Resnet18 and Sgdm performs best, FCN 32s with Sgdm takes the second, and U-Net with Adam ranks third. This paper also analyzes the segmentation strategies of the three networks in terms of feature map visualization. Results show that the contour generated by DeepLab v3+ (combined with Resnet18 and Sgdm) is closest to the ground truth, while the resulting contour of U-Net (combined with Adam) is closest to the input images.

关键词: slope damage     image recognition     semantic segmentation     feature map     visualizations    

Finite element analysis of controlled low strength materials

Vahid ALIZADEH

《结构与土木工程前沿(英文)》 2019年 第13卷 第5期   页码 1243-1250 doi: 10.1007/s11709-019-0553-3

摘要: Controlled low strength materials (CLSM) are flowable and self-compacting construction materials that have been used in a wide variety of applications. This paper describes the numerical modeling of CLSM fills with finite element method under compression loading and the bond performance of CLSM and steel rebar under pullout loading. The study was conducted using a plastic-damage model which captures the material behavior using both classical theory of elasto-plasticity and continuum damage mechanics. The capability of the finite element approach for the analysis of CLSM fills was assessed by a comparison with the experimental results from a laboratory compression test on CLSM cylinders and pullout tests. The analysis shows that the behavior of a CLSM fill while subject to a failure compression load or pullout tension load can be simulated in a reasonably accurate manner.

关键词: CLSM     finite element method     compressive strength     pullout     numerical modeling     plastic damage model    

基于人工神经网络的多处损伤加筋板剩余强度预测

杨茂胜,陈跃良,郁大照

《中国工程科学》 2008年 第10卷 第5期   页码 46-50

摘要:

用BP神经网络算法对多处损伤加筋板的剩余强度数据进行训练学习,将预测值和3种经典分析方法的计算值与实验值进行对比,结果表明,ANN法预测值与实验值吻合得最好,LMC修正法和WSU3修正法次之,Swift塑性区连通法最差。最后用所建立的BP网络对不同主裂纹半长和韧带长度的剩余强度进行了预测,结果发现,在其他参数不变的情况下,不管是双筋条还是三筋条加筋板,剩余强度总是随主裂纹半长的增加而成线性降低,随韧带长度的增加而成线性增加,但双筋条加筋板比三筋条加筋板对主裂纹半长和韧带长度的变化更加敏感。

关键词: 神经网络     多处损伤     加筋板     剩余强度    

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

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    

Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

《结构与土木工程前沿(英文)》 2016年 第10卷 第1期   页码 63-71 doi: 10.1007/s11709-015-0294-x

摘要: A composite structural system consisting of prefabricated reinforced concrete frame with infill slit shear walls (PRCFW), with good ductility, is a new type of earthquake resistant structure. Pseudo-static tests were performed to evaluate the seismic behavior of the PRCFW system. Two one-bay, two-story PRCFW specimens were both built at one-half scale. Additional computational research is also conducted to enhance the nonlinear analytical capabilities for this system. Combined with the concrete damaged plastic (CDP) model provided by finite element program ABAQUS and the constitutive model of concrete proposed by Chinese code, the damage process of the PRCFW structure under cyclic load is simulated. The simulated results show a good agreement with the test data, the dynamic behavior of the PRCFW system can be simulated sufficiently accurate and efficient to provide useful design information. The experimental and numerical study show that this system has the potential to offer good ductility and energy absorption capacity to dissipate input energy, and stiffness adequate for controlling drift for buildings located in earthquake-prone regions.

关键词: slit shear wall     constitutive model     cyclic     seismic     damage    

标题 作者 时间 类型 操作

An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

期刊论文

Endochronic damage constitutive model for fully-graded aggregate mass concrete

SONG Yupu, WANG Huailiang

期刊论文

Nonlinear cumulative damage model for multiaxial fatigue

SHANG De-guang, SUN Guo-qin, DENG Jing, YAN Chu-liang

期刊论文

Damage-constitutive model for seawater coral concrete using different stirrup confinements subjected

期刊论文

An efficient two-stage approach for structural damage detection using meta-heuristic algorithms and groupmethod of data handling surrogate model

Hamed FATHNEJAT, Behrouz AHMADI-NEDUSHAN

期刊论文

Damage mechanism and evaluation model of compressor impeller remanufacturing blanks: A review

Haiyang LU, Yanle LI, Fangyi LI, Xingyi ZHANG, Chuanwei ZHANG, Jiyu DU, Zhen LI, Xueju RAN, Jianfeng LI, Weiqiang WANG

期刊论文

Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

João Pedro SANTOS,Christian CREMONA,André D. ORCESI,Paulo SILVEIRA,Luis CALADO

期刊论文

Regional seismic-damage prediction of buildings under mainshock–aftershock sequence

Xinzheng LU, Qingle CHENG, Zhen XU, Chen XIONG

期刊论文

Intermediate HSS bracing members during seismic excitations: modeling, design, and behavior

Madhar HADDAD

期刊论文

Uncertainty quantification of stability and damage detection parameters of coupled hydrodynamic-ground

Nazim Abdul NARIMAN, Tom LAHMER, Peyman KARAMPOUR

期刊论文

Optimal CNN-based semantic segmentation model of cutting slope images

Mansheng LIN; Shuai TENG; Gongfa CHEN; Jianbing LV; Zhongyu HAO

期刊论文

Finite element analysis of controlled low strength materials

Vahid ALIZADEH

期刊论文

基于人工神经网络的多处损伤加筋板剩余强度预测

杨茂胜,陈跃良,郁大照

期刊论文

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

Abdelwahhab KHATIR; Roberto CAPOZUCCA; Samir KHATIR; Erica MAGAGNINI

期刊论文

Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

期刊论文