资源类型

期刊论文 293

会议视频 1

年份

2024 1

2023 14

2022 27

2021 29

2020 23

2019 15

2018 12

2017 11

2016 10

2015 17

2014 15

2013 10

2012 12

2011 10

2010 14

2009 22

2008 5

2007 15

2006 10

2005 6

展开 ︾

关键词

安全系数 5

影响因素 5

对策 2

岩爆 2

数值模拟 2

疲劳寿命 2

2型糖尿病 1

Colebrook隐式方程 1

GVG农情采样系统 1

HHT 1

Logistic分析 1

Matlab仿真 1

PWM 1

Q值监测 1

三星一线 1

乙酰肝素酶 1

交叉模态 1

人工流产 1

人格素质 1

展开 ︾

检索范围：

排序： 展示方式：

Development of temperature-robust damage factor based on sensor fusion for a wind turbine structure

Jong-Woong PARK,Sung-Han SIM,Jin-Hak YI,Hyung-Jo JUNG

《结构与土木工程前沿（英文）》 2015年 第9卷 第1期   页码 42-47 doi: 10.1007/s11709-014-0285-3

摘要： Wind power systems have gained much attention due to the relatively high reliability, maturity in technology and cost competitiveness compared to other renewable alternatives. Advances have been made to increase the power efficiency of the wind turbines while less attention has been focused on structural integrity assessment of the structural systems. Vibration-based damage detection has widely been researched to identify damages on a structure based on change in dynamic characteristics. Widely spread methods are natural frequency-based, mode shape-based, and curvature mode shape-based methods. The natural frequency-based methods are convenient but vulnerable to environmental temperature variation which degrades damage detection capability; mode shapes are less influenced by temperature variation and able to locate damage but requires extensive sensor instrumentation which is costly and vulnerable to signal noises. This study proposes novelty of damage factor based on sensor fusion to exclude effect of temperature variation. The combined use of an accelerometer and an inclinometer was considered and damage factor was defined as a change in relationship between those two measurements. The advantages of the proposed method are: 1) requirement of small number of sensor, 2) robustness to change in temperature and signal noise and 3) ability to roughly locate damage. Validation of the proposed method is carried out through numerical simulation on a simplified 5 MW wind turbine model.

关键词： sensor fusion     damage detection     structural health monitoring    

HTML PDF 收藏

The damage evolution behavior of polypropylene fiber reinforced concrete subjected to sulfate attack

Ninghui LIANG; Jinwang MAO; Ru YAN; Xinrong LIU; Xiaohan ZHOU

《结构与土木工程前沿（英文）》 2022年 第16卷 第3期   页码 316-328 doi: 10.1007/s11709-022-0810-8

摘要： To study the damage evolution behavior of polypropylene fiber reinforced concrete (PFRC) subjected to sulfate attack, a uniaxial compression test was carried out based on acoustic emission (AE). The effect of sulfate attack relative to time and fiber hybridization were analyzed and the compression damage factor was calculated using a mathematical model. The changes to AE ringing counts during the compression could be divided into compaction, elastic, and AE signal hyperactivity stages. In the initial stage of sulfate attack, the concrete micropores and microcracks were compacted gradually under external load and a corrosion products filling effect, and this corresponded with detection of few AE signals and with concrete compression strength enhancement. With increasing sulfate attack time, AE activity decreased. The cumulative AE ringing counts of PFRC at all corrosion ages were much higher than those for plain concrete. PFRC could still produce AE signals after peak load due to drawing effect of polypropylene fiber. After 150 d of sulfate attack, the cumulative AE ringing counts of plain concrete went down by about an order of magnitude, while that for PFRC remained at a high level. The initial damage factor of hybrid PFRC was −0.042 and −0.056 respectively after 150 d of corrosion, indicating that the advantage of hybrid polypropylene fiber was more obvious than plain concrete and single-doped PFRC. Based on a deterioration equation, the corrosion resistance coefficient of hybrid PFRC would be less than 0.75 after 42 drying−wetting sulfate attack cycles, which was 40% longer than that of plain concrete.

关键词： polypropylene fiber reinforced concrete     sulfate attack     damage evolution behavior     acoustic emission     damage factor    

HTML PDF 收藏

Windborne debris damage prediction analysis

Fangfang SONG, Jinping OU,

《结构与土木工程前沿（英文）》 2010年 第4卷 第3期   页码 326-330 doi: 10.1007/s11709-010-0067-5

摘要： Windborne debris is one of the most important causes of the envelop destruction according to the post-damage investigations. The problem of windborne debris damage could be summarized as three parts, including windborne debris risk analysis, debris flying trajectories, and impact resistance of envelope analysis. The method of debris distribution is developed. The flying trajectories of compact and plate-like debris are solved by using a numerical method according to the different aerodynamic characteristics. The impact resistance of the envelopes is also analyzed. Besides, the process of windborne debris damage analysis is described in detail. An example of industrial building is given to demonstrate the whole method by using the observed data of typhoon Chanchu (2006). The method developed in this paper could be applied to risk assessment of windborne debris for structures in wind hazard.

关键词： typhoon     windborne debris     structural envelopes     damage estimation    

HTML PDF 收藏

Corrosion damage assessment and monitoring of large steel space structures

Bo CHEN, You-Lin XU, Weilian QU,

《结构与土木工程前沿（英文）》 2010年 第4卷 第3期   页码 354-369 doi: 10.1007/s11709-010-0088-0

摘要： Large steel space structures, when exposed to a harsh corrosive environment, are inevitably subjected to atmospheric corrosion and stress corrosion cracking. This paper proposes a framework for assessing the corrosion damage of large steel space structures subjected to both stress corrosion cracking and atmospheric corrosion. The empirical model for estimating atmospheric corrosion based on measured information is briefly introduced. The proposed framework is applied to a real large steel space structure built in the southern coastal area in China to assess its corrosion damage and investigate the effects of atmospheric corrosion on stress corrosion cracking. Based on the results, the conceptual design of the corrosion monitoring system of large steel space structures is finally conducted as the first step for a real corrosion monitoring system.

关键词： large steel space structure     atmospheric corrosion     stress corrosion cracking     corrosion damage     damage assessment     monitoring system    

HTML PDF 收藏

Detection of damage locations and damage steps in pile foundations using acoustic emissions with deep

Alipujiang JIERULA, Tae-Min OH, Shuhong WANG, Joon-Hyun LEE, Hyunwoo KIM, Jong-Won LEE

《结构与土木工程前沿（英文）》 2021年 第15卷 第2期   页码 318-332 doi: 10.1007/s11709-021-0715-y

摘要： The aim of this study is to propose a new detection method for determining the damage locations in pile foundations based on deep learning using acoustic emission data. First, the damage location is simulated using a back propagation neural network deep learning model with an acoustic emission data set acquired from pile hit experiments. In particular, the damage location is identified using two parameters: the pile location ( ) and the distance from the pile cap ( ). This study investigates the influences of various acoustic emission parameters, numbers of sensors, sensor installation locations, and the time difference on the prediction accuracy of and . In addition, correlations between the damage location and acoustic emission parameters are investigated. Second, the damage step condition is determined using a classification model with an acoustic emission data set acquired from uniaxial compressive strength experiments. Finally, a new damage detection and evaluation method for pile foundations is proposed. This new method is capable of continuously detecting and evaluating the damage of pile foundations in service.

关键词： pile foundations     damage location     acoustic emission     deep learning     damage step    

HTML PDF 收藏

Creep life assessment of aero-engine recuperator based on continuum damage mechanics approach

《机械工程前沿（英文）》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0702-6

摘要： The creep life of an aeroengine recuperator is investigated in terms of continuum damage mechanics by using finite element simulations. The effects of the manifold wall thickness and creep properties of brazing filler metal on the operating life of the recuperator are analyzed. Results show that the crack initiates from the brazing filler metal located on the outer surface of the manifold with the wall thickness of 2 mm and propagates throughout the whole region of the brazing filler metal when the creep time reaches 34900 h. The creep life of the recuperator meets the requirement of 40000 h continuous operation when the wall thickness increases to 3.5 mm, but its total weight increases by 15%. Decreasing the minimum creep strain rate with the enhancement of the creep strength of the brazing filler metal presents an obvious effect on the creep life of the recuperator. At the same stress level, the creep rupture time of the recuperator is enhanced by 13 times if the mismatch between the minimum creep rate of the filler and base metal is reduced by 20%.

关键词： creep     life assessment     brazed joint     continuum damage mechanics     aeroengine recuperator    

HTML PDF 收藏

Bacterial inactivation, DNA damage, and faster ATP degradation induced by ultraviolet disinfection

Chao Yang, Wenjun Sun, Xiuwei Ao

《环境科学与工程前沿（英文）》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1192-6

摘要： • Long amplicon is more effective to test DNA damage induced by UV. • ATP in bacteria does not degrade instantly but does eventually after UV exposure. • After medium pressure UV exposure, ATP degraded faster. The efficacy of ultraviolet (UV) disinfection has been validated in numerous studies by using culture-based methods. However, the discovery of viable but non-culturable bacteria has necessitated the investigation of UV disinfection based on bacterial viability parameters. We used quantitative polymerase chain reaction (qPCR) to investigate DNA damage and evaluated adenosine triphosphate (ATP) to indicate bacterial viability. The results of qPCR effectively showed the DNA damage induced by UV when using longer gene amplicons, in that sufficiently long amplicons of both 16S and gadA indicated that the UV induced DNA damages. The copy concentrations of the long amplicons of 16S and gadA decreased by 2.38 log/mL and 1.88 log/mL, respectively, after exposure to 40 mJ/cm2 low-pressure UV. After UV exposure, the ATP level in the bacteria did not decrease instantly. Instead it decreased gradually at a rate that was positively related to the UV fluence. For low-pressure UV, this rate of decrease was slow, but for medium pressure UV, this rate of decrease was relatively high when the UV fluence reached 40 mJ/cm2. At the same UV fluence, the ATP level in the bacteria decreased at a faster rate after exposure to medium-pressure UV.

关键词： UV disinfection     DNA damage     qPCR     ATP    

HTML PDF 收藏

Spectral element modeling based structure piezoelectric impedance computation and damage identification

Zhigang GUO, Zhi SUN

《结构与土木工程前沿（英文）》 2011年 第5卷 第4期   页码 458-464 doi: 10.1007/s11709-011-0133-7

摘要： This paper presents a numerical simulation study on electromechanical impedance technique for structural damage identification. The basic principle of impedance based damage detection is structural impedance will vary with the occurrence and development of structural damage, which can be measured from electromechanical admittance curves acquired from PZT patches. Therefore, structure damage can be identified from the electromechanical admittance measurements. In this study, a model based method that can identify both location and severity of structural damage through the minimization of the deviations between structural impedance curves and numerically computed response is developed. The numerical model is set up using the spectral element method, which is promised to be of high numerical efficiency and computational accuracy in the high frequency range. An optimization procedure is then formulated to estimate the property change of structural elements from the electric admittance measurement of PZT patches. A case study on a pin-pin bar is conducted to investigate the feasibility of the proposed method. The results show that the presented method can accurately identify bar damage location and severity even when the measurements are polluted by 5% noise.

关键词： PZT     piezoelectric impedance     optimization     spectral element     damage identification    

HTML PDF 收藏

Damage detection in beam-like structures using static shear energy redistribution

《结构与土木工程前沿（英文）》 2022年 第16卷 第12期   页码 1552-1564 doi: 10.1007/s11709-022-0903-4

摘要： In this study, a static shear energy algorithm is presented for the damage assessment of beam-like structures. According to the energy release principle, the strain energy of a damaged element suddenly changes when structural damage occurs. Therefore, the change in the static shear energy is employed to determine the damage locations in beam-like structures. The static shear energy is derived from the spectral factorization of the elementary stiffness matrix and structural deflection variation. The advantage of using shear energy as opposed to total energy is that only a few deflection data points of the beam structure are required during the process of damage identification. Another advantage of the proposed approach is that damage detection can be performed without establishing a structural finite-element model in advance. The proposed technique is first validated using a numerical example with single, multiple, and adjacent damage scenarios. A channel steel beam and rectangular concrete beam are employed as experimental cases to further verify the proposed approach. The results of the simulation and experiment examples indicate that the proposed algorithm provides a simple and effective method for defect localization in beam-like structures.

关键词： damage detection     beam structure     strain energy     static displacement variation     energy damage index    

HTML PDF 收藏

Temperature effects of shape memory alloys (SMAs) in damage control design of steel portal frames

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI

《结构与土木工程前沿（英文）》 2012年 第6卷 第4期   页码 348-357 doi: 10.1007/s11709-012-0176-4

摘要： The objective of the present study is to analytically investigate temperature effects of an axial-type seismic damper made of shape memory alloys (SMAs) equipped in steel frames. Based on a modified multilinear one dimensional constitutive model of SMAs, two types of SMAs are employed, which have different stress plateau and different stress growth rate with temperature increase. Temperature effects of SMA dampers on seismic performance upgrading are discussed in three aspects: different environment temperatures; rapid loading rate induced heat generation and different SMA fractions. The analysis indicates that the effect of environment temperature should be considered for the SMA damper in steel frames. However, the rapid loading rate induced heat generation has little adverse effect.

关键词： damage control design     shape memory alloy     temperature effect    

HTML PDF 收藏

Numerical simulation of damage in high arch dam due to earthquake

Hong ZHONG , Gao LIN , Hongjun LI

《结构与土木工程前沿（英文）》 2009年 第3卷 第3期   页码 316-322 doi: 10.1007/s11709-009-0039-9

摘要： Based on the assumption that concrete is macroscopic homogeneous, the cracking evolution process and damage mode of high arch dams are studied in consideration of the heterogeneity of concrete in mesoscale. The bilinear damage evolution model and the damage evolution model expressed in power function with descending section are adopted to combine with the Mohr-Coulomb criterion to investigate the crack development and fracture mode of high arch dams under the action of an earthquake. The analysis result of a high arch dam in China under design shows that cracks that take place in concrete are caused by excessive tensile stress. The cracks initiate at the middle of the dam top and distribute at the upper half of the dam while the rest of the parts remain intact. This conclusion agrees with the model test result.

关键词： mesoscopic heterogeneity     damage simulation in earthquakes     arch dam    

HTML PDF 收藏

Influence of construction-induced damage on the degradation of freeze–thawed lightweight cellular concrete

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 781-792 doi: 10.1007/s11709-021-0733-9

摘要： During the construction of lightweight cellular concrete (LCC), material damage frequently occurs, causing the degradation and deterioration of the mechanical performance, durability, and subgrade quality of LCC. The construction-induced damage can be more significant than those from the service environment of LCC, such as freeze–thaw (F–T) action in cold regions. However, the effect of construction-induced damage on LCC during F–T cycles is often ignored and the deterioration mechanisms are not yet clarified. In this study, we investigated the factors causing damage during construction using a sample preparation method established to simulate the damage in the laboratory setting. We conducted F–T cycle tests and microstructural characterization to study the effect of microstructural damage on the overall strength of LCC with different water contents under F–T actions. We established the relationship between the pore-area ratio and F–T cycle times, pore-area ratio, and strength, as well as the F–T cycle times and strength under different damage forms. The damage evolution is provided with the rationality of the damage equation, verified by comparing the measured and predicted damage variables. This study would serve as a guide for the construction and performance of LCC in cold regions.

关键词： lightweight cellular concrete     construction-induced damage     freeze-thaw action     microstructure     degradation mechanism    

HTML PDF 收藏

A Stoneley wave method to detect interlaminar damage of metal layer composite pipe

Bing LI,Lei QIANG,Tong LU,Xu GENG,Minghang LI

《机械工程前沿（英文）》 2015年 第10卷 第1期   页码 89-94 doi: 10.1007/s11465-015-0323-4

摘要：

The interlaminar defect is a major form of damage in metal layer composite pipes which are widely used in petroleum and chemical industry. In this paper, a Stoneley wave method is presented to detect interlaminar damage in laminated pipe structure. Stoneley wave possesses some good characteristics, such as high energy and large displacement at the interface and non-dispersive in the high-frequency, so the sensitivity of detecting interlaminar damage can be improved and the higher frequency can be used in damage detection compared with Lamb waves. Additionally, as the frequency increases, the wavelength of the Stoneley wave reduces. Thus, its ability to detect small defects at the interface is enhanced. Finite element model of metal layer composite pipe with interlaminar damage is used to simulate wave propagation of Lamb waves and Stoneley wave, respectively. The damage location is calculated by using the Stoneley wave signal obtained from finite element model, and then the results are compared with the actual damage locations. The simulation examples demonstrate that the Stoneley wave method can better identify the interlaminar damage in laminated pipe structure compared with Lamb waves.

关键词： Stoneley wave     interlaminar damage     metal laminated pipe    

HTML PDF 收藏

Crack propagation with different radius local random damage based on peridynamic theory

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1238-1248 doi: 10.1007/s11709-021-0695-y

摘要： Drawing from the advantages of Classical Mechanics, the peridynamic theory can clarify the crack propagation mechanism by an integral solution without initially setting the factitious crack and crack path. This study implements the peridynamic theory by subjecting bilateral notch cracked specimens to the conditions of no local damage, small radius local damage, and large radius local damage. Moreover, to study the effects of local stochastic damage with different radii on the crack propagation path and Y-direction displacement, a comparison and contact methodology was adopted, in which the crack propagation paths under uniaxial tension and displacement in the Y-direction were compared and analyzed. This method can be applied to steel structures under similar local random damage conditions.

关键词： peridynamics     stochastic damage     bilateral notch crack    

HTML PDF 收藏

A combination of damage locating vector method (DLV) and differential evolution algorithm (DE) for structuraldamage assessment

T. NGUYEN-THOI, A. TRAN-VIET, N. NGUYEN-MINH, T. VO-DUY, V. HO-HUU

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 92-108 doi: 10.1007/s11709-016-0379-1

摘要： In this study, a two-stage method is presented for identifying multiple damage scenarios. In the first stage, the damage locating vector (DLV) method using normalized cumulative energy ( ) is employed for damage localization in structures. In the second stage, the differential evolution algorithm (DE) is used for damage severity of the structures. In addition, in the second stage, a modification of an available objective function is made for handing the issue of symmetric structures. To verify the effectiveness of the present technique, numerical examples of a 72-bar space truss and a one-span steel portal frame are considered. In addition, the effect of noise on the performance of the identification results is also investigated. The numerical results show that the proposed combination gives good assessment of damage location and extent for multiple structural damage cases.

关键词： damage assessment     damage locating vector method (DLV)     differential evolution (DE)     multiple damage location assurance criterion (MDLAC)     mode shape error function    

HTML PDF 收藏

标题 作者 时间 类型 操作

Development of temperature-robust damage factor based on sensor fusion for a wind turbine structure

Jong-Woong PARK,Sung-Han SIM,Jin-Hak YI,Hyung-Jo JUNG

期刊论文

The damage evolution behavior of polypropylene fiber reinforced concrete subjected to sulfate attack

Ninghui LIANG; Jinwang MAO; Ru YAN; Xinrong LIU; Xiaohan ZHOU

期刊论文

Windborne debris damage prediction analysis

Fangfang SONG, Jinping OU,

期刊论文

Corrosion damage assessment and monitoring of large steel space structures

Bo CHEN, You-Lin XU, Weilian QU,

期刊论文

Detection of damage locations and damage steps in pile foundations using acoustic emissions with deep

Alipujiang JIERULA, Tae-Min OH, Shuhong WANG, Joon-Hyun LEE, Hyunwoo KIM, Jong-Won LEE

期刊论文

Creep life assessment of aero-engine recuperator based on continuum damage mechanics approach

期刊论文

Bacterial inactivation, DNA damage, and faster ATP degradation induced by ultraviolet disinfection

Chao Yang, Wenjun Sun, Xiuwei Ao

期刊论文

Spectral element modeling based structure piezoelectric impedance computation and damage identification

Zhigang GUO, Zhi SUN

期刊论文

Damage detection in beam-like structures using static shear energy redistribution

期刊论文

Temperature effects of shape memory alloys (SMAs) in damage control design of steel portal frames

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI

期刊论文

Numerical simulation of damage in high arch dam due to earthquake

Hong ZHONG , Gao LIN , Hongjun LI

期刊论文

Influence of construction-induced damage on the degradation of freeze–thawed lightweight cellular concrete

期刊论文

A Stoneley wave method to detect interlaminar damage of metal layer composite pipe

Bing LI,Lei QIANG,Tong LU,Xu GENG,Minghang LI

期刊论文

Crack propagation with different radius local random damage based on peridynamic theory

期刊论文

A combination of damage locating vector method (DLV) and differential evolution algorithm (DE) for structuraldamage assessment

T. NGUYEN-THOI, A. TRAN-VIET, N. NGUYEN-MINH, T. VO-DUY, V. HO-HUU

期刊论文