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参数估计 2

岩爆 2

运动估计 2

2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型 1

Arrhenius模型 1

CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

GVG农情采样系统 1

HHT 1

ICI）；最大似然估计（maximum likelihood estimation 1

LS算法 1

MLE） 1

OFDM 1

OFDM）；快速傅立叶变换（Fast Fourier transform， FFT）；循环前缀（cyclic prefix 1

SARS危机 1

SWAT模型 1

Weibull分布 1

不确定性评估 1

二维波达角估计；信道冲击响应估计；信号检测；均匀矩形阵列；大规模天线 1

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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    

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Estimation of fatigue damage of airplane landing gear

LIU Ke-ge, YAN Chu-liang, ZHANG Shu-ming

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 424-428 doi: 10.1007/s11465-006-0051-x

摘要： Taking the main landing gears of fighter and transport airplanes as examples, the fatigue life was estimated by means of the Miner s rule and from the spectrum of the real measurements. The computed results show that the landing damage to the fighter and transport airplanes is 75% and 60% of the total damage, and the damage caused by the landing stroke is 40% of the landing-gear damage. The fatigue damage properties can provide important information for reliable designing and the structural optimization.
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The use of Artificial Neural Networks to estimate seismic damage and derive vulnerability functions for

Tiago Miguel FERREIRA, João ESTÊVÃO, Rui MAIO, Romeu VICENTE

《结构与土木工程前沿（英文）》 2020年 第14卷 第3期   页码 609-622 doi: 10.1007/s11709-020-0623-6

摘要： This paper discusses the adoption of Artificial Intelligence-based techniques to estimate seismic damage, not with the goal of replacing existing approaches, but as a mean to improve the precision of empirical methods. For such, damage data collected in the aftermath of the 1998 Azores earthquake (Portugal) is used to develop a comparative analysis between damage grades obtained resorting to a classic damage formulation and an innovative approach based on Artificial Neural Networks (ANNs). The analysis is carried out on the basis of a vulnerability index computed with a hybrid seismic vulnerability assessment methodology, which is subsequently used as input to both approaches. The results obtained are then compared with real post-earthquake damage observation and critically discussed taking into account the level of adjustment achieved by each approach. Finally, a computer routine that uses the ANN as an approximation function is developed and applied to derive a new vulnerability curve expression. In general terms, the ANN developed in this study allowed to obtain much better approximations than those achieved with the original vulnerability approach, which has revealed to be quite non-conservative. Similarly, the proposed vulnerability curve expression was found to provide a more accurate damage prediction than the traditional analytical expressions.

关键词： Artificial Neural Networks     seismic vulnerability     masonry buildings     damage estimation     vulnerability curves    

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A dynamic stiffness-based framework for harmonic input estimation and response reconstruction consideringdamage

Yixian LI; Limin SUN; Wang ZHU; Wei ZHANG

《结构与土木工程前沿（英文）》 2022年 第16卷 第4期   页码 448-460 doi: 10.1007/s11709-022-0805-5

摘要： In structural health monitoring (SHM), the measurement is point-wise but structures are continuous. Thus, input estimation has become a hot research subject with which the full-field structural response can be calculated with a finite element model (FEM). This paper proposes a framework based on the dynamic stiffness theory, to estimate harmonic input, reconstruct responses, and to localize damages from seriously deficient measurements. To begin, Fourier transform converts the dynamic equilibrium equation to an equivalent static one in the frequency domain, which is under-determined since the dimension of measurement vector is far less than the FEM-node number. The principal component analysis has been adopted to “compress” the under-determined equation, and formed an over-determined equation to estimate the unknown input. Then, inverse Fourier transform converts the estimated input in the frequency domain to the time domain. Applying this to the FEM can reconstruct the target responses. If a structure is damaged, the estimated nodal force can localize the damage. To improve the damage-detection accuracy, a multi-measurement-based indicator has been proposed. Numerical simulations have validated that the proposed framework can capably estimate input and reconstruct multi-types of full-field responses, and the damage indicator can localize minor damages even with the existence of noise.

关键词： dynamic stiffness     principal component analysis     response reconstruction     damage localization     under-determined equation    

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基于图像处理的超高速撞击碎片云的动态建模与损伤估计 Research Article

曾入,宋燕,吕伟臻

《信息与电子工程前沿（英文）》 2022年 第23卷 第4期   页码 555-570 doi: 10.1631/FITEE.2100049

摘要： 由于难以从实验中获得高质量碎片云图像，对薄板上超高速撞击产生的碎片云进行轨迹建模和有效损伤估计一直是一项具有挑战性的任务。为提高超高速撞击对典型双层板防护结构损伤的估计精度，本文结合传统数值分析结果，利用图像处理技术，研究了连续阴影图中碎片云的分布特征。本文的目标是从图像处理获取的阴影图中提取碎片云的目标运动参数，并构建轨迹模型用来估计损伤。在超高速撞击实验中，我们从超高速序列激光阴影成像设备中获得8个连续阴影图片帧，从中选择4个具有代表性的帧用于后续特征分析。然后，利用去噪和分割等图像处理技术，从连续图像帧中提取特殊碎片特征。在提取的信息基础上，进行碎片图像匹配，并根据匹配的碎片对碎片云的轨迹进行建模。本文方法获得的结果与传统数值推导结果的对比表明，从图像处理中获取超高速撞击实验数据的方法可以为改进数值模拟方法提供关键信息。最后，基于所构建的模型，提出一种改进的后壁损伤估计方法。估计的损坏与后墙实际损坏情况的对比证明了所提模型的有效性。

关键词： 碎片云；超高速撞击；图像处理；损伤估计    

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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    

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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    

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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    

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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    

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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    

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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    

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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    

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Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution

L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY

《能源前沿（英文）》 2012年 第6卷 第1期   页码 47-56 doi: 10.1007/s11708-011-0159-5

摘要： The advancement in power distribution system poses a great challenge to power engineering researchers on how to best monitor and estimate the state of the distribution network. This paper is executed in two stage processes. The first stage is to identify the optimal location for installation of monitoring instrument with minimal investment cost. The second stage is to estimate the bus voltage magnitude, where real time measurement is conducted and measured through identified meter location which is more essential for decision making in distribution supervisory control and data acquisition system (DSCADA). The hybrid intelligent technique is applied to execute the above two algorithms. The algorithms are tested with institute of electrical and electronics engineers (IEEE) and Tamil Nadu electricity board (TNEB) benchmark systems. The simulated results proves that the swarm tuned artificial neural network (ANN) estimator is best suited for accurate estimation of voltage with different noise levels.

关键词： artificial intelligence     power distribution control     state estimation    

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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    

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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    

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标题 作者 时间 类型 操作

Windborne debris damage prediction analysis

Fangfang SONG, Jinping OU,

期刊论文

Estimation of fatigue damage of airplane landing gear

LIU Ke-ge, YAN Chu-liang, ZHANG Shu-ming

期刊论文

The use of Artificial Neural Networks to estimate seismic damage and derive vulnerability functions for

Tiago Miguel FERREIRA, João ESTÊVÃO, Rui MAIO, Romeu VICENTE

期刊论文

A dynamic stiffness-based framework for harmonic input estimation and response reconstruction consideringdamage

Yixian LI; Limin SUN; Wang ZHU; Wei ZHANG

期刊论文

基于图像处理的超高速撞击碎片云的动态建模与损伤估计

曾入,宋燕,吕伟臻

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

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

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

Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution

L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY

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